With the continuous development of computer network technology, it has been widely used in all walks of life, and gradually penetrated into people's life and learning, giving people great convenience, but it also ...With the continuous development of computer network technology, it has been widely used in all walks of life, and gradually penetrated into people's life and learning, giving people great convenience, but it also poses a serious network security threat to people's information. Therefore, in order to avoid the threat of network security, many technical colleges in China have specially set up computer network complete teaching courses, and are teaching students relevant computer security courses. However, in the actual teaching process, many computers will have various problems in teaching network security technology, and the teaching funds of technical colleges are limited. Therefore, in order to meet the learning needs of students and good teaching effect, virtual machine technology is introduced. This technology can greatly reduce the teaching funds and promote the smooth development of computer network security teaching, in order to achieve better teaching effect.展开更多
The 2018 Joint International Congress of ILTS,ELITA and LICAGE were held in Lisbon,Portugal on May 23–26,2018.The exciting and innovative program brought together 1144 experts in liver transplantation(LT)such as surg...The 2018 Joint International Congress of ILTS,ELITA and LICAGE were held in Lisbon,Portugal on May 23–26,2018.The exciting and innovative program brought together 1144 experts in liver transplantation(LT)such as surgeons,physicians or basic scientists from 61 countries.The presentations included 110 invited speakers,181 oral presentations,and 545 posters.This editorial highlights some of the most innovative and impactful presentations in展开更多
Fiber reinforced ceramic matrix composites(FRCMCs)are the preferred materials for safety critical components in the fields of aerospace,nuclear engineering,and transportation,with broad market and application prospect...Fiber reinforced ceramic matrix composites(FRCMCs)are the preferred materials for safety critical components in the fields of aerospace,nuclear engineering,and transportation,with broad market and application prospects.However,due to the characteristics of multiphase,heterogeneity,and anisotropy,key issues such as poor adhesion,high porosity,and crack propagation urgently need to be addressed in the fabrication and machining of FRCMCs.With the increasing demand for FRCMCs parts,high-quality and reliable design and fabrication,performance evaluation,and precision manufacturing have become a series of hot issues.There is a lack of systematic review in capturing the current research status and development direction of FRCMCs fabrication and machining.This research aims to comprehensively review and critically evaluate the existing understanding of the fabrication and machining of FRCMCs.This study can provide scientists with a deeper understanding of the shape control mechanism of FRCMCs fabrication and machining,the theoretical basis of material synchronous removal,machining performance,and development direction.Firstly,the basic characteristics and application background of FRCMCs are introduced.Secondly,by comparing and analyzing the typical fabrication process of FRCMCs,the advantages,disadvantages,and performance evaluation of different processes are comprehensively evaluated.Thirdly,the material removal mechanisms and machining performance evaluation standards of traditional mechanical machining technologies(drilling,milling,grinding)and non-traditional mechanical machining technologies(ultrasonic,laser,water jet,discharge,wire saw,and multi-field hybrid machining)are discussed and analyzed.Finally,the challenges,development trends,and prospects faced by FRCMCs in the fields of fabrication,machining,and application are analyzed.This study not only elucidates the basic processes and key difficulties in the fabrication of FRCMCs,but also provides valuable insights for low-damage machining.展开更多
In this study, we established a dynamic morphological model using the accumulated thermal effectiveness and photosynthetic active radiation （PAR） （A-TEP）, aiming to explore the relationship between muskmelon （Cuc...In this study, we established a dynamic morphological model using the accumulated thermal effectiveness and photosynthetic active radiation （PAR） （A-TEP）, aiming to explore the relationship between muskmelon （Cucumis melo L.） fruit attributes and environmental factors. Muskmelon surface color was described by parameters of red, green, blue, hue, saturation and brightness （HSI）. Three characteristic parameters, gray level co-occurrence matrix （GLCM）, angular second moment （ASM）, entropy, contrast, and the coverage rate were used to describe the process of muskmelon fruit netting formation. ASM was not significant difference during muskmelon fruit growth. The number and deep of netting stripes gradually increased with fruit growth. Coverage rate increased rapidly for 15-30 d after pollination. The vertical and horizontal diameters of muskmelon fruit were followed a logistic curve. And root mean squared errors （RMSE） between the simulated and measured vertical and horizontal diameters were 3.527 and 4.696 mm, respectively. RMSE of red, green, blue, saturation and brightness were 0.999, 2.690, 2.992, 0.033 and 5.51, respectively, and the RMSE for entropy, contrast and coverage rates were 0.077, 0.063 and 0.015, respectively, indicating a well consistent between measured and simulated values.展开更多
This paper presents a terahertz（THz）band-pass filter using ultra-precision machining technology based on Chebyshev filter prototype.This iris inductive window coupled waveguide filter was designed by using 8 resonan...This paper presents a terahertz（THz）band-pass filter using ultra-precision machining technology based on Chebyshev filter prototype.This iris inductive window coupled waveguide filter was designed by using 8 resonant cavities with a center frequency of 345 GHz and a 7% bandwidth.The final design fulfills the desired specifications and presents the minimum insertion loss of 1.55 d B and the return loss of less than 15 d B at 345 GHz.The stop-band rejection is50 d B off the center frequency about 30 GHz,which means it has a good performance of high stop-band suppression.Compared with the recent development of THz filters,this filter possesses the characteristic of simple structure and is easy to machining.展开更多
Modern mechanical manufacturing technology and precision machining technology have a positive role in promoting the whole industrial production. However, with the development of modern science and technology, the actu...Modern mechanical manufacturing technology and precision machining technology have a positive role in promoting the whole industrial production. However, with the development of modern science and technology, the actual requirements of modern mechanical manufacturing technology and precision machining technology are gradually improving, forcing the current enterprises to make appropriate adjustments in combination with the actual requirements of modern industrial production. Therefore, under the requirements of current production management, this paper makes a comprehensive analysis and exploration of the relationship between modern mechanical manufacturing technology and precision processing technology, further combs out the practical problems existing in the whole industrial production of modern mechanical manufacturing technology and precision processing technology, and judges the relevant contents involved in the modern mechanical manufacturing and processing technology, in order to promote the transformation of industrial production mode and improve the overall quality of industrial production management in our country.展开更多
Gears are important mechanical parts for transmitting power and play an increasingly important role in the machinery industry.The electric vehicle industry developed rapidly and became a vital development field of the...Gears are important mechanical parts for transmitting power and play an increasingly important role in the machinery industry.The electric vehicle industry developed rapidly and became a vital development field of the automotive industry over the past few years.The conversion of energy increases the requirements for electric vehicle transmissions,which promotes the development of high-speed and low-noise transmission gear.This paper elaborates on the research progress of high-speed and low-noise gear finishing methods.Firstly,this review analyses the machining requirements,finishing,and specific machining technologies of high-speed and low-noise gears.The importance of gear grinding and honing in high-speed and low-noise gear machining is highlighted.Secondly,the applications of gear grinding and honing in gear modification,error compensation,and texture control are analyzed.Furthermore,the role of precision machining technology in improving gear performance is clarified.Finally,the design and processing methods of the modified tooth flank for gear modification are summarized.In addition,the influence of tooth surface texture on noise is described,and the texture change methods are explored.The well-known open problems of gear finishing are finally identified,and some new research interests are also pointed out.This review will provide valuable references for further research on gear finishing.展开更多
Aero-engines,the core of air travel,rely on advanced high strength-toughness alloys(THSAs)such as titanium alloys,nickel-based superalloys,intermetallics,and ultra-high strength steel.The precision of cutting techniqu...Aero-engines,the core of air travel,rely on advanced high strength-toughness alloys(THSAs)such as titanium alloys,nickel-based superalloys,intermetallics,and ultra-high strength steel.The precision of cutting techniques is crucial for the manufacture of key components,including blades,discs,shafts,and gears.However,machining THSAs pose significant challenges,including high cutting forces and temperatures,which lead to rapid tool wear,reduced efficiency,and compromised surface integrity.This review thoroughly explores the current landscape and future directions of cutting techniques for THSAs in aero-engines.It examines the principles,mechanisms,and benefits of energy-assisted cutting technologies like laser-assisted machining and cryogenic cooling.The review assesses various tool preparation methods,their effects on tool performance,and strategies for precise shape and surface integrity control.It also outlines intelligent monitoring technologies for machining process status,covering aspects such as tool wear,surface roughness,and chatter,contributing to intelligent manufacturing.Additionally,it highlights emerging trends and potential future developments,including multi-energy assisted cutting mechanisms,advanced cutting tools,and collaborative control of structure shape and surface integrity,alongside intelligent monitoring software and hardware.This review serves as a reference for achieving efficient and high-quality manufacturing of THSAs in aero-engines.展开更多
Ganoderma lucidum,a medicinal mushroom renowned for its production of a diverse array of compounds,accounts for the pharmacological effects including anti-infammatory,antioxidant,immunomodulatory,and anticancer charac...Ganoderma lucidum,a medicinal mushroom renowned for its production of a diverse array of compounds,accounts for the pharmacological effects including anti-infammatory,antioxidant,immunomodulatory,and anticancer characteristics.Thus,it is recognized as a valuable species of interest in the pharmaceutical and nutraceutical industries due to its important medicinal properties.Recent advances in omics technologies such as genomes,transcriptomics,proteomics,and metabolomics have considerably increased our understanding of the bioactives in G.lucidum.This review explores the application of molecular breeding techniques to enhance both the yield and quality of G.lucidum across the food,pharmaceutical,and industrial sectors.The article discusses the current state of research on the use of contemporary omics technologies which studies and highlights future research directions that may increase the production of bioactive compounds for their therapeutic potential.Additionally,predictive methods with computational studies have recently emerged as effective tools for investigating bioactive constituents in G.lucidum,providing an organized and cost-effective strategy for understanding their bioactivity,interactions,and possible therapeutic uses.Omics and machine learning techniques can be applied to identify the candidates for pharmaceutical applications and to enhance the production of bioactive compounds in G.lucidum.The quantifcation and production of the bioactive compounds can be streamlined by the integrating computational study of bioactive compounds with non-destructive predictive machine learning models of the same.Synergistically,these techniques have the potential to be a promising approach for the future prediction of the bioactive constituents,without compromising the integrity of the fungal organism.展开更多
So many potential risks can be identifed for application of trenchless technology especially using microtunneling methods.Unexpected changes in ground conditions,such as encountering boulders,tree roots,ground water a...So many potential risks can be identifed for application of trenchless technology especially using microtunneling methods.Unexpected changes in ground conditions,such as encountering boulders,tree roots,ground water and man-made structures such as old foundations are the principal geotechnical risks,which affect the selection of an appropriate microtunnel boring machine.On the other hand,the performance of each microtunneling technique will differ while encountering such conditions.Hence,predicting the potential hazards provides a better safety and risk management plan.In this study,a couple of potentially hazardous situation,which are commonly associated with ground conditions,were identifed and investigated.A decision tree aid methodology was proposed based on geotechnical risk assessment for selection of proper microtunneling technique.Based on the approach the most appropriate microtunneling technique has the minimum risk level either before or after hazards mitigation measures.In order to check the effciency of the approach in practice,selection of microtunnel boring machine for Hamadan sewerage pipeline project was evaluated.Accordingly,an earth pressure balance(EPB)MTBM was selected for the project.展开更多
Machine learning is the use of computers to learn the intrinsic laws and information contained in data through algorithms to gain new experience and knowledge,in order to improve the intelligence of computers,so that ...Machine learning is the use of computers to learn the intrinsic laws and information contained in data through algorithms to gain new experience and knowledge,in order to improve the intelligence of computers,so that they can make decisions similar to those made by humans when faced with problems.With the development of various industries,the amount of data has increased and the efficiency of data processing and analysis has become more demanding,a series of machine learning algorithms have emerged.Machine learning algorithms are essentially steps and processes that apply a large number of statistical principles to solve optimisation problems.Appropriate machine learning algorithms can be used to solve practical problems more efficiently for a wide range of model requirements.This paper presents the interim state of a dynamic disruption management software solution for logistics,using machine learning methods to study the extent to which stress is predicted based on physiological and subjective parameters,to prevent physical and mental stress on workers in the logistics industry,to maintain their health,to make them more optimistic and better able to adapt to their work,and to facilitate more accurate deployment of human resources by companies according to the real-time requirements of the logistics industry.展开更多
Near infrared spectroscopy （NIR） is now probably the most popular process analytical technology （PAT） for pharmaceutical and some other industries. However, unlike mid-IR, NIR is known to have difficulties in moni...Near infrared spectroscopy （NIR） is now probably the most popular process analytical technology （PAT） for pharmaceutical and some other industries. However, unlike mid-IR, NIR is known to have difficulties in monitoring crystallization or precipitation processes because the existence of solids could cause distortion of the spectra. This phenomenon, seen as unfavorable previously, is however an indication that NIR spectra contain rich information about both solids and liquids, giving the possibility of using the same instrument for multiple property characterization. In this study, transflectance NIR calibration data was obtained using solutions and slurries of varied solution concentration, particle size, solid concentration and temperature. The data was used to build calibration models for prediction of the multiple properties of both phases. Predictive models were developed for this challenging application using an approach that combines genetic algorithm （GA） and support vector machine （SVM）. GA is used for wavelength selection and SVM for mode building. The new GA-SVM approach is shown to outperform other methods including GA-PLS （partial least squares） and traditional SVM. NIR is thus successfully applied to monitoring seeded and unseeded cooling crystallization processes of L-glutamic acid.展开更多
文摘With the continuous development of computer network technology, it has been widely used in all walks of life, and gradually penetrated into people's life and learning, giving people great convenience, but it also poses a serious network security threat to people's information. Therefore, in order to avoid the threat of network security, many technical colleges in China have specially set up computer network complete teaching courses, and are teaching students relevant computer security courses. However, in the actual teaching process, many computers will have various problems in teaching network security technology, and the teaching funds of technical colleges are limited. Therefore, in order to meet the learning needs of students and good teaching effect, virtual machine technology is introduced. This technology can greatly reduce the teaching funds and promote the smooth development of computer network security teaching, in order to achieve better teaching effect.
基金supported by grants from China Postdoctoral Science Foundation(2017M610374)National Natural Science Foundation of China(81470891)+2 种基金Science and Technology Bureau of Zhejiang Province,China(2016C33145)Innovative Research Groups of the National Natural Science Foundation of China(81421062)the Fundamental Research Funds for the Central Universities(2018FZA7003)
文摘The 2018 Joint International Congress of ILTS,ELITA and LICAGE were held in Lisbon,Portugal on May 23–26,2018.The exciting and innovative program brought together 1144 experts in liver transplantation(LT)such as surgeons,physicians or basic scientists from 61 countries.The presentations included 110 invited speakers,181 oral presentations,and 545 posters.This editorial highlights some of the most innovative and impactful presentations in
基金supported by Key Laboratory of Higheffciency and Clean Mechanical Manufacture at Shandong University,Ministry of Education,the National Natural Science Foundation of China(Nos.52305484,52305475,and U23A20632)the China Postdoctoral Science Foundation(No.2024M761876)+7 种基金the Youth Innovation Team Program of Universities in Shandong Province(No.2024KJH166)the National Key Research and Development Program of China(No.2023YFC2413301)the Taishan Scholars Program(No.tsqn202408242)the Shandong Provincial Natural Science Foundation(Nos.ZR2022QE053 and ZR2022QE159)the Guangdong Basic and Applied Basic Research Foundation(No.2022A1515111124)the Major Scientific and Technological Innovation Project of Shandong Province(No.2023CXGC010207)the Major Basic Research of Shandong Provincial Natural Science Foundation(No.ZR2023ZD34)the talent research project for the pilot project of integrating science,education,and industries of Qilu University of Technology(Shandong Academy of Sciences)(No.2024RCKY009)。
文摘Fiber reinforced ceramic matrix composites(FRCMCs)are the preferred materials for safety critical components in the fields of aerospace,nuclear engineering,and transportation,with broad market and application prospects.However,due to the characteristics of multiphase,heterogeneity,and anisotropy,key issues such as poor adhesion,high porosity,and crack propagation urgently need to be addressed in the fabrication and machining of FRCMCs.With the increasing demand for FRCMCs parts,high-quality and reliable design and fabrication,performance evaluation,and precision manufacturing have become a series of hot issues.There is a lack of systematic review in capturing the current research status and development direction of FRCMCs fabrication and machining.This research aims to comprehensively review and critically evaluate the existing understanding of the fabrication and machining of FRCMCs.This study can provide scientists with a deeper understanding of the shape control mechanism of FRCMCs fabrication and machining,the theoretical basis of material synchronous removal,machining performance,and development direction.Firstly,the basic characteristics and application background of FRCMCs are introduced.Secondly,by comparing and analyzing the typical fabrication process of FRCMCs,the advantages,disadvantages,and performance evaluation of different processes are comprehensively evaluated.Thirdly,the material removal mechanisms and machining performance evaluation standards of traditional mechanical machining technologies(drilling,milling,grinding)and non-traditional mechanical machining technologies(ultrasonic,laser,water jet,discharge,wire saw,and multi-field hybrid machining)are discussed and analyzed.Finally,the challenges,development trends,and prospects faced by FRCMCs in the fields of fabrication,machining,and application are analyzed.This study not only elucidates the basic processes and key difficulties in the fabrication of FRCMCs,but also provides valuable insights for low-damage machining.
基金supported by the National Natural Science Foundation of China (31471411)the Shanghai Agriculture Applied Technology Development Program,China ((2017)3-8-4)
文摘In this study, we established a dynamic morphological model using the accumulated thermal effectiveness and photosynthetic active radiation （PAR） （A-TEP）, aiming to explore the relationship between muskmelon （Cucumis melo L.） fruit attributes and environmental factors. Muskmelon surface color was described by parameters of red, green, blue, hue, saturation and brightness （HSI）. Three characteristic parameters, gray level co-occurrence matrix （GLCM）, angular second moment （ASM）, entropy, contrast, and the coverage rate were used to describe the process of muskmelon fruit netting formation. ASM was not significant difference during muskmelon fruit growth. The number and deep of netting stripes gradually increased with fruit growth. Coverage rate increased rapidly for 15-30 d after pollination. The vertical and horizontal diameters of muskmelon fruit were followed a logistic curve. And root mean squared errors （RMSE） between the simulated and measured vertical and horizontal diameters were 3.527 and 4.696 mm, respectively. RMSE of red, green, blue, saturation and brightness were 0.999, 2.690, 2.992, 0.033 and 5.51, respectively, and the RMSE for entropy, contrast and coverage rates were 0.077, 0.063 and 0.015, respectively, indicating a well consistent between measured and simulated values.
基金supported by the National Natural Science Foundation of China under Grant No.61434006
文摘This paper presents a terahertz（THz）band-pass filter using ultra-precision machining technology based on Chebyshev filter prototype.This iris inductive window coupled waveguide filter was designed by using 8 resonant cavities with a center frequency of 345 GHz and a 7% bandwidth.The final design fulfills the desired specifications and presents the minimum insertion loss of 1.55 d B and the return loss of less than 15 d B at 345 GHz.The stop-band rejection is50 d B off the center frequency about 30 GHz,which means it has a good performance of high stop-band suppression.Compared with the recent development of THz filters,this filter possesses the characteristic of simple structure and is easy to machining.
文摘Modern mechanical manufacturing technology and precision machining technology have a positive role in promoting the whole industrial production. However, with the development of modern science and technology, the actual requirements of modern mechanical manufacturing technology and precision machining technology are gradually improving, forcing the current enterprises to make appropriate adjustments in combination with the actual requirements of modern industrial production. Therefore, under the requirements of current production management, this paper makes a comprehensive analysis and exploration of the relationship between modern mechanical manufacturing technology and precision processing technology, further combs out the practical problems existing in the whole industrial production of modern mechanical manufacturing technology and precision processing technology, and judges the relevant contents involved in the modern mechanical manufacturing and processing technology, in order to promote the transformation of industrial production mode and improve the overall quality of industrial production management in our country.
基金Supported by National Natural Science Foundation of China(Grant Nos.52275483,52075142,and U22B2084)the Fundamental Research Funds for the Central Universities of China(Grant No.JZ2023HGPA0292).
文摘Gears are important mechanical parts for transmitting power and play an increasingly important role in the machinery industry.The electric vehicle industry developed rapidly and became a vital development field of the automotive industry over the past few years.The conversion of energy increases the requirements for electric vehicle transmissions,which promotes the development of high-speed and low-noise transmission gear.This paper elaborates on the research progress of high-speed and low-noise gear finishing methods.Firstly,this review analyses the machining requirements,finishing,and specific machining technologies of high-speed and low-noise gears.The importance of gear grinding and honing in high-speed and low-noise gear machining is highlighted.Secondly,the applications of gear grinding and honing in gear modification,error compensation,and texture control are analyzed.Furthermore,the role of precision machining technology in improving gear performance is clarified.Finally,the design and processing methods of the modified tooth flank for gear modification are summarized.In addition,the influence of tooth surface texture on noise is described,and the texture change methods are explored.The well-known open problems of gear finishing are finally identified,and some new research interests are also pointed out.This review will provide valuable references for further research on gear finishing.
基金National Natural Science Foundation of China(Nos.92160301,92060203,52175415,and 52205475)Science Center for Gas Turbine Project(No.P2023-B-IV-003-001)+1 种基金Natural Science Foundation of Jiangsu Province(No.BK20210295)Fundamental Research Funds for the Central Universities(Nos.NS2023028 and NG2024015)。
文摘Aero-engines,the core of air travel,rely on advanced high strength-toughness alloys(THSAs)such as titanium alloys,nickel-based superalloys,intermetallics,and ultra-high strength steel.The precision of cutting techniques is crucial for the manufacture of key components,including blades,discs,shafts,and gears.However,machining THSAs pose significant challenges,including high cutting forces and temperatures,which lead to rapid tool wear,reduced efficiency,and compromised surface integrity.This review thoroughly explores the current landscape and future directions of cutting techniques for THSAs in aero-engines.It examines the principles,mechanisms,and benefits of energy-assisted cutting technologies like laser-assisted machining and cryogenic cooling.The review assesses various tool preparation methods,their effects on tool performance,and strategies for precise shape and surface integrity control.It also outlines intelligent monitoring technologies for machining process status,covering aspects such as tool wear,surface roughness,and chatter,contributing to intelligent manufacturing.Additionally,it highlights emerging trends and potential future developments,including multi-energy assisted cutting mechanisms,advanced cutting tools,and collaborative control of structure shape and surface integrity,alongside intelligent monitoring software and hardware.This review serves as a reference for achieving efficient and high-quality manufacturing of THSAs in aero-engines.
基金funded by DST-SERB,Govt.of India under the CRG project vide sanction order number CRG/2021/001815the financial support of the European Union under the REFRESH–Research Excellence for region Sustainability and High-tech Industries(No.CZ.10.03.01/00/22_003/0000048)via the operational Programme Just Transitionpartially carried out at the Jet Propulsion Laboratory,California Institute of Technology,under a contract with the National Aeronautics and Space Administration(No.80NM0018D0004)。
文摘Ganoderma lucidum,a medicinal mushroom renowned for its production of a diverse array of compounds,accounts for the pharmacological effects including anti-infammatory,antioxidant,immunomodulatory,and anticancer characteristics.Thus,it is recognized as a valuable species of interest in the pharmaceutical and nutraceutical industries due to its important medicinal properties.Recent advances in omics technologies such as genomes,transcriptomics,proteomics,and metabolomics have considerably increased our understanding of the bioactives in G.lucidum.This review explores the application of molecular breeding techniques to enhance both the yield and quality of G.lucidum across the food,pharmaceutical,and industrial sectors.The article discusses the current state of research on the use of contemporary omics technologies which studies and highlights future research directions that may increase the production of bioactive compounds for their therapeutic potential.Additionally,predictive methods with computational studies have recently emerged as effective tools for investigating bioactive constituents in G.lucidum,providing an organized and cost-effective strategy for understanding their bioactivity,interactions,and possible therapeutic uses.Omics and machine learning techniques can be applied to identify the candidates for pharmaceutical applications and to enhance the production of bioactive compounds in G.lucidum.The quantifcation and production of the bioactive compounds can be streamlined by the integrating computational study of bioactive compounds with non-destructive predictive machine learning models of the same.Synergistically,these techniques have the potential to be a promising approach for the future prediction of the bioactive constituents,without compromising the integrity of the fungal organism.
文摘So many potential risks can be identifed for application of trenchless technology especially using microtunneling methods.Unexpected changes in ground conditions,such as encountering boulders,tree roots,ground water and man-made structures such as old foundations are the principal geotechnical risks,which affect the selection of an appropriate microtunnel boring machine.On the other hand,the performance of each microtunneling technique will differ while encountering such conditions.Hence,predicting the potential hazards provides a better safety and risk management plan.In this study,a couple of potentially hazardous situation,which are commonly associated with ground conditions,were identifed and investigated.A decision tree aid methodology was proposed based on geotechnical risk assessment for selection of proper microtunneling technique.Based on the approach the most appropriate microtunneling technique has the minimum risk level either before or after hazards mitigation measures.In order to check the effciency of the approach in practice,selection of microtunnel boring machine for Hamadan sewerage pipeline project was evaluated.Accordingly,an earth pressure balance(EPB)MTBM was selected for the project.
文摘Machine learning is the use of computers to learn the intrinsic laws and information contained in data through algorithms to gain new experience and knowledge,in order to improve the intelligence of computers,so that they can make decisions similar to those made by humans when faced with problems.With the development of various industries,the amount of data has increased and the efficiency of data processing and analysis has become more demanding,a series of machine learning algorithms have emerged.Machine learning algorithms are essentially steps and processes that apply a large number of statistical principles to solve optimisation problems.Appropriate machine learning algorithms can be used to solve practical problems more efficiently for a wide range of model requirements.This paper presents the interim state of a dynamic disruption management software solution for logistics,using machine learning methods to study the extent to which stress is predicted based on physiological and subjective parameters,to prevent physical and mental stress on workers in the logistics industry,to maintain their health,to make them more optimistic and better able to adapt to their work,and to facilitate more accurate deployment of human resources by companies according to the real-time requirements of the logistics industry.
基金UK Engineering and Physical Sciences Research Council for funding the research (EPSRCGrant Reference: EP/C001788/1)
文摘Near infrared spectroscopy （NIR） is now probably the most popular process analytical technology （PAT） for pharmaceutical and some other industries. However, unlike mid-IR, NIR is known to have difficulties in monitoring crystallization or precipitation processes because the existence of solids could cause distortion of the spectra. This phenomenon, seen as unfavorable previously, is however an indication that NIR spectra contain rich information about both solids and liquids, giving the possibility of using the same instrument for multiple property characterization. In this study, transflectance NIR calibration data was obtained using solutions and slurries of varied solution concentration, particle size, solid concentration and temperature. The data was used to build calibration models for prediction of the multiple properties of both phases. Predictive models were developed for this challenging application using an approach that combines genetic algorithm （GA） and support vector machine （SVM）. GA is used for wavelength selection and SVM for mode building. The new GA-SVM approach is shown to outperform other methods including GA-PLS （partial least squares） and traditional SVM. NIR is thus successfully applied to monitoring seeded and unseeded cooling crystallization processes of L-glutamic acid.
