The construction of the tunnel face is a critical aspect of tunnel excavation,and its supporting equipment mainly includes drilling jumbos,arch installation trolleys,wet spraying manipulators,and anchor bolt trolleys....The construction of the tunnel face is a critical aspect of tunnel excavation,and its supporting equipment mainly includes drilling jumbos,arch installation trolleys,wet spraying manipulators,and anchor bolt trolleys.To address the issues of high construction costs and the need to replace equipment for different processes,this paper designs an economical and practical multi-functional integrated trolley based on engineering cases.This trolley is suitable for various construction methods such as full-face excavation and benching method,and integrates functions such as drilling and blasting holes,anchor bolt holes,advance grouting holes,pipe roof construction,charging,anchor bolt installation and grouting,and arch mesh installation.It reduces the number of operators,improves the tunnel working environment,lowers construction costs,and enhances construction efficiency.展开更多
Extracorporeal liver surgery(ELS), also known as liver autotransplantation, is a hybrid(cross-fertilized) surgery incorporating the technical knowledge from extreme liver and transplant liver surgeries, and recently b...Extracorporeal liver surgery(ELS), also known as liver autotransplantation, is a hybrid(cross-fertilized) surgery incorporating the technical knowledge from extreme liver and transplant liver surgeries, and recently became more embraced and popularized among leading centers. ELS could be summarized into three major categories, namely, ex-situ liver resection and autotransplantation(ELRA), ante-situm liver resection and autotransplantation(ALRA) and auxiliary partial liver autotransplantation(APLA). The successful development of ELS during the past 37 years is definitely inseparable from continuous effort s done by Chinese surgeons and researchers. Especially, the precision liver surgery paradigm has allowed to transform ELS into a modularized, more simplified, and standardized surgery, to upgrade surgical skills, to improve peri-operative outcome and long-term survival, to increase the capability of surgeons to select more complex diseases and to expand the level of medical service to the population. This review highlights the Chinese contributions to the field of ELS, focusing thereby on features of different surgical types, technical innovations, disease selection and surgical indication, patient prognosis and future perspectives.展开更多
The Macao Science Satellite-1(MSS-1)is the first space science satellite jointly developed on the Chinese mainland and in Macao region.It comprises two satellites,named MSS-1A and MSS-1B,and holds considerable importa...The Macao Science Satellite-1(MSS-1)is the first space science satellite jointly developed on the Chinese mainland and in Macao region.It comprises two satellites,named MSS-1A and MSS-1B,and holds considerable importance in China’s space exploration endeavors.Among these,MSS-1A is the world’s first high-precision scientific satellite dedicated to exploring the geomagnetic field and space environment at low latitudes.Equipped with two high-precision vector magnetometers and one scalar magnetometer,which are integrally installed on a highly stable nonmagnetic optical bench,the MSS-1A enables simultaneous high-precision measurements of both the Earth’s vector magnetic field and its scalar components.Its design integrates several state-of-the-art technologies,including arc-second-level thermal stability control,nonmagnetic thermal control for the optical bench,and ultra-high magnetic cleanliness control.These innovations effectively minimize magnetic interference originating from the satellite itself,thereby substantially improving the precision of geomagnetic field measurements and establishing a robust technical foundation for future magnetic survey satellite constellations.展开更多
With the rapid development of high-speed railway tunnel construction mileage and technology,the construction of the tunnel face is a key part of tunnel construction in high-speed railway tunnel projects.As mechanizati...With the rapid development of high-speed railway tunnel construction mileage and technology,the construction of the tunnel face is a key part of tunnel construction in high-speed railway tunnel projects.As mechanization and intelligence levels continue to increase,supporting equipment mainly includes rock drilling trolleys,arch installation trolleys,wet spraying robots,anchor trolleys,etc.To address the issues of high construction costs and the need to replace equipment for different processes,this paper designs an economical and practical multi-functional integrated trolley for high-speed railway double-track tunnels based on engineering cases.This trolley can adapt to various tunnel face excavation methods such as the full-face method and the bench method,enabling integrated functions such as drilling and blasting holes,anchor holes,advance grouting holes,pipe roof construction,charging,anchor installation and grouting,and arch mesh installation.This reduces the number of operators,improves the working environment of high-speed railway tunnels,lowers construction costs,and enhances construction efficiency.展开更多
The dynamic model of the ball screw mechanism(BSM)in spatial motion,developed in Part I of the study titled‘research and experimental analysis on precision degradation of BSM at low speed’,has been validated through...The dynamic model of the ball screw mechanism(BSM)in spatial motion,developed in Part I of the study titled‘research and experimental analysis on precision degradation of BSM at low speed’,has been validated through a comparison between calculated values and experimentally measured data obtained from a comprehensive ball-screw test bench.In order to study the perform-ance parameters related to the precision degradation characteristics of ball screw under different pre-loads and speeds,the precision degradation test bench for ball screw is set up.Through the experi-ment on the ball-screw comprehensive test bench,the drag torque,stroke deviation,acceleration peak value,axial contact stiffness and other parameters of the BSM under different speeds are ob-tained,and the different preloads are obtained by the drag torque,the changing regularity of which is consistent with the simulation results.A comprehensive analysis of the experimental data reveals that the dynamic characteristics of the ball screw’s spatial motion are significantly influenced by gy-roscopic torque effects.By incorporating these parametric effects,the accuracy degradation charac-teristics of ball screw under different preloads and speeds can be well analyzed.This methodology establishes a technical foundation for investigating ball screw accuracy retention characteristics.展开更多
For strapdown stabilized platform used in automatic vertical drilling system,a new dynamic measurement algorithm based on three-axis accelerometer and three-axis fluxgate measurement signals is proposed and simulated ...For strapdown stabilized platform used in automatic vertical drilling system,a new dynamic measurement algorithm based on three-axis accelerometer and three-axis fluxgate measurement signals is proposed and simulated under the condition of small inclination dynamic rotation.The error compensation algorithm is also proposed.The bench test of strapdown stabilized platform is designed and carried out.The results show that:When the azimuth angle is the same,the larger the inclination angle is,the greater the error of the measurement results will be.When the inclination angle is the same,the measurement error is the largest when the azimuth angle is 90°and 270°,and the measurement error curve presents a sinusoidal change with the change of azimuth angle.After the error function compensation,the error curve between the calculation results and the true value is basically not affected by the inclination angle and the azimuth angle,and the calculation accuracy is signifi cantly improved.Under the random rotating speed of 0-180 rpm,the minimum error of the measured well inclination value was no more than 0.03°and the maximum was no more than 1.58°.The feasibility of the proposed dynamic azimuth measurement algorithm is verifi ed.This article provides a technical reference for the strapdown automatic drilling system.展开更多
This paper introduces a kind of substitute bench testing method for vehicle application development and testing method of the test requirements,including battery fast conversion cycle test equipment,enter type incubat...This paper introduces a kind of substitute bench testing method for vehicle application development and testing method of the test requirements,including battery fast conversion cycle test equipment,enter type incubator,liquid-cooled machine and ancillary equipment composed of a set of test system,through the walk-in constant temperature box to simulate the new energy vehicles under different environmental conditions of the test requirements,Liquid-cooled machine and auxiliary parts to complete the battery thermal management system need cooling fluid conditions,the battery conversion cycle test equipment to simulate the dc fast charging way of filling pile,complete battery thermal management system test,shorten the filling fast charging time and improve battery fast charge security,for troubleshooting and data collection and analysis,Improve work efficiency,save costs,and eliminate customer anxiety about battery life and charging time.展开更多
The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavio...The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service environment.This paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was created.Acceleration responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was studied.Meanwhile,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was identified.Finally,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic modeling.The results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating condition.It was also found that the torque affects the modal param-eter of the gearbox significantly.The torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently.展开更多
In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face ...In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.展开更多
Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in th...Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in these industries, it can also have multiple adverse environmental impacts. One such effect is flyrock, which poses risks to nearby machinery, and residential structures, and can even lead to injuries or fatalities. To optimize blasting efficiency as well as restrict side effects, prediction of the blast aftereffects is vital. Therefore, the present work focuses on using two machine learning methods to predict the velocity of flyrock in the open pit mine. To address this issue, a comprehensive dataset was gathered from the open pit mine. Then, Decision Tree and Random Forest algorithms were employed to predict flyrock velocity. The Random Forest model demonstrated superior performance compared to the Decision Tree model. Nonetheless, the performance of the Decision Tree model was deemed satisfactory, as evidenced by its coefficient of determination value of 0.83, mean squared error (MSE) of 4.2, and mean absolute percentage error (MAPE) of 5.6%. Considering these metrics, it is reasonable to conclude that tree-based algorithms can be effective in predicting flyrock velocity.展开更多
转化医学（translational medicine）,也称转化研究（translational research）,是医学领域的新概念[1—2],强调把生物基础研究的最新成果快速有效地转化为临床医学技术的过程,即从实验室到病床（bench to bedside）再从病床到实验室（b...转化医学（translational medicine）,也称转化研究（translational research）,是医学领域的新概念[1—2],强调把生物基础研究的最新成果快速有效地转化为临床医学技术的过程,即从实验室到病床（bench to bedside）再从病床到实验室（bedside to bench）的双向连续过程,简称为“B-to-B或B2B”。康复医学是有别于临床医学的以“功能障碍”患者为服务对象的学科[3]。展开更多
针对一种硬质烟用滤棒的复合添加需求,设计一种烟用滤棒上下料机构。采用瞬态动力学分析方法,运用ANSYS Work Bench软件对滤棒上下料机构进行瞬态动力学仿真,并从结构动力学角度对该机构进行动态特性研究。分析结果显示,滤棒上下料机构...针对一种硬质烟用滤棒的复合添加需求,设计一种烟用滤棒上下料机构。采用瞬态动力学分析方法,运用ANSYS Work Bench软件对滤棒上下料机构进行瞬态动力学仿真,并从结构动力学角度对该机构进行动态特性研究。分析结果显示,滤棒上下料机构的最大等效应力112.54 MPa,小于材料的许用应力。通过搭建实验平台进行试验,验证该滤棒上下料机构的合理性及稳定性。研究结果表明:滤棒上下料机构结构设计合理,取料成功率达到100%,能够满足工作要求。展开更多
The paper reviews the development of prediction formulas for the fragmentation from bench blasting.Much attention has been paid to the Kuz-Ram model,its development and errors,and the mean vs.median misunderstanding.T...The paper reviews the development of prediction formulas for the fragmentation from bench blasting.Much attention has been paid to the Kuz-Ram model,its development and errors,and the mean vs.median misunderstanding.The work by the US Bureau of Mines(USBM)and Chung and Katsabanis are also reviewed,as well as the two Julius Kruttschnitt Mineral Research Centre(JKMRC)models,i.e.the crush zone model(CZM)and the two-component model(TCM),which were developed to cope with the underestimation of blasting fines.The change brought by the Swebrec distribution and the associated Kuznetsov-Cunningham-Ouchterlony(KCO)model is described.Studying distribution-free fragment sizes xP for an arbitrary mass passing P led to the discovery of the fragmentation-energy fan,and with the help of dimensional analysis,to the new fragmentation prediction model xP-frag,which has much lower errors than those of the Kuz-Ram and CZM models.展开更多
文摘The construction of the tunnel face is a critical aspect of tunnel excavation,and its supporting equipment mainly includes drilling jumbos,arch installation trolleys,wet spraying manipulators,and anchor bolt trolleys.To address the issues of high construction costs and the need to replace equipment for different processes,this paper designs an economical and practical multi-functional integrated trolley based on engineering cases.This trolley is suitable for various construction methods such as full-face excavation and benching method,and integrates functions such as drilling and blasting holes,anchor bolt holes,advance grouting holes,pipe roof construction,charging,anchor bolt installation and grouting,and arch mesh installation.It reduces the number of operators,improves the tunnel working environment,lowers construction costs,and enhances construction efficiency.
基金supported by grants from the Beijing Hospitals Authority Youth Program (12022B4010)BTCH Young Talent En-lightenment Program (2024QMRC24)CAMS Innovation Fund for Medical Sciences (2019-I2M-5–056)。
文摘Extracorporeal liver surgery(ELS), also known as liver autotransplantation, is a hybrid(cross-fertilized) surgery incorporating the technical knowledge from extreme liver and transplant liver surgeries, and recently became more embraced and popularized among leading centers. ELS could be summarized into three major categories, namely, ex-situ liver resection and autotransplantation(ELRA), ante-situm liver resection and autotransplantation(ALRA) and auxiliary partial liver autotransplantation(APLA). The successful development of ELS during the past 37 years is definitely inseparable from continuous effort s done by Chinese surgeons and researchers. Especially, the precision liver surgery paradigm has allowed to transform ELS into a modularized, more simplified, and standardized surgery, to upgrade surgical skills, to improve peri-operative outcome and long-term survival, to increase the capability of surgeons to select more complex diseases and to expand the level of medical service to the population. This review highlights the Chinese contributions to the field of ELS, focusing thereby on features of different surgical types, technical innovations, disease selection and surgical indication, patient prognosis and future perspectives.
文摘The Macao Science Satellite-1(MSS-1)is the first space science satellite jointly developed on the Chinese mainland and in Macao region.It comprises two satellites,named MSS-1A and MSS-1B,and holds considerable importance in China’s space exploration endeavors.Among these,MSS-1A is the world’s first high-precision scientific satellite dedicated to exploring the geomagnetic field and space environment at low latitudes.Equipped with two high-precision vector magnetometers and one scalar magnetometer,which are integrally installed on a highly stable nonmagnetic optical bench,the MSS-1A enables simultaneous high-precision measurements of both the Earth’s vector magnetic field and its scalar components.Its design integrates several state-of-the-art technologies,including arc-second-level thermal stability control,nonmagnetic thermal control for the optical bench,and ultra-high magnetic cleanliness control.These innovations effectively minimize magnetic interference originating from the satellite itself,thereby substantially improving the precision of geomagnetic field measurements and establishing a robust technical foundation for future magnetic survey satellite constellations.
文摘With the rapid development of high-speed railway tunnel construction mileage and technology,the construction of the tunnel face is a key part of tunnel construction in high-speed railway tunnel projects.As mechanization and intelligence levels continue to increase,supporting equipment mainly includes rock drilling trolleys,arch installation trolleys,wet spraying robots,anchor trolleys,etc.To address the issues of high construction costs and the need to replace equipment for different processes,this paper designs an economical and practical multi-functional integrated trolley for high-speed railway double-track tunnels based on engineering cases.This trolley can adapt to various tunnel face excavation methods such as the full-face method and the bench method,enabling integrated functions such as drilling and blasting holes,anchor holes,advance grouting holes,pipe roof construction,charging,anchor installation and grouting,and arch mesh installation.This reduces the number of operators,improves the working environment of high-speed railway tunnels,lowers construction costs,and enhances construction efficiency.
基金Supported by the National Natural Science Foundation of China(No.51575014,51505020)the Key Foundation Project of China Academy of Railway Sciences(No.2021YJ200).
文摘The dynamic model of the ball screw mechanism(BSM)in spatial motion,developed in Part I of the study titled‘research and experimental analysis on precision degradation of BSM at low speed’,has been validated through a comparison between calculated values and experimentally measured data obtained from a comprehensive ball-screw test bench.In order to study the perform-ance parameters related to the precision degradation characteristics of ball screw under different pre-loads and speeds,the precision degradation test bench for ball screw is set up.Through the experi-ment on the ball-screw comprehensive test bench,the drag torque,stroke deviation,acceleration peak value,axial contact stiffness and other parameters of the BSM under different speeds are ob-tained,and the different preloads are obtained by the drag torque,the changing regularity of which is consistent with the simulation results.A comprehensive analysis of the experimental data reveals that the dynamic characteristics of the ball screw’s spatial motion are significantly influenced by gy-roscopic torque effects.By incorporating these parametric effects,the accuracy degradation charac-teristics of ball screw under different preloads and speeds can be well analyzed.This methodology establishes a technical foundation for investigating ball screw accuracy retention characteristics.
基金The financial supports from National key plan project for research and development of China (2019YFA0708300) and (2023YFC3009200)。
文摘For strapdown stabilized platform used in automatic vertical drilling system,a new dynamic measurement algorithm based on three-axis accelerometer and three-axis fluxgate measurement signals is proposed and simulated under the condition of small inclination dynamic rotation.The error compensation algorithm is also proposed.The bench test of strapdown stabilized platform is designed and carried out.The results show that:When the azimuth angle is the same,the larger the inclination angle is,the greater the error of the measurement results will be.When the inclination angle is the same,the measurement error is the largest when the azimuth angle is 90°and 270°,and the measurement error curve presents a sinusoidal change with the change of azimuth angle.After the error function compensation,the error curve between the calculation results and the true value is basically not affected by the inclination angle and the azimuth angle,and the calculation accuracy is signifi cantly improved.Under the random rotating speed of 0-180 rpm,the minimum error of the measured well inclination value was no more than 0.03°and the maximum was no more than 1.58°.The feasibility of the proposed dynamic azimuth measurement algorithm is verifi ed.This article provides a technical reference for the strapdown automatic drilling system.
文摘This paper introduces a kind of substitute bench testing method for vehicle application development and testing method of the test requirements,including battery fast conversion cycle test equipment,enter type incubator,liquid-cooled machine and ancillary equipment composed of a set of test system,through the walk-in constant temperature box to simulate the new energy vehicles under different environmental conditions of the test requirements,Liquid-cooled machine and auxiliary parts to complete the battery thermal management system need cooling fluid conditions,the battery conversion cycle test equipment to simulate the dc fast charging way of filling pile,complete battery thermal management system test,shorten the filling fast charging time and improve battery fast charge security,for troubleshooting and data collection and analysis,Improve work efficiency,save costs,and eliminate customer anxiety about battery life and charging time.
基金The authors are grateful for the financial support from the National Key Research and Development Program of China(Grant No.2021YFB3400701)the Fundamental Research Funds for the Central Universities(Science and technology leading talent team project,Grant No.2022JBQY007).
文摘The high-speed train transmission system,experiencing both the internal excitation originating from gear meshing and the external excitation originating from the wheel-rail interaction,exhibits complex dynamic behavior in the actual service environment.This paper focuses on the gearbox in the high-speed train to carry out the bench test,in which various operat-ing conditions(torques and rotation speeds)were set up and the excitation condition covering both internal and external was created.Acceleration responses on multiple positions of the gearbox were acquired in the test and the vibration behavior of the gearbox was studied.Meanwhile,a stochastic excitation modal test was also carried out on the test bench under different torques,and the modal parameter of the gearbox was identified.Finally,the sweep frequency response of the gearbox under gear meshing excitation was analyzed through dynamic modeling.The results showed that the torque has an attenuating effect on the amplitude of gear meshing frequency on the gearbox,and the effect of external excitation on the gearbox vibration cannot be ignored,especially under the rated operating condition.It was also found that the torque affects the modal param-eter of the gearbox significantly.The torque has a great effect on both the gear meshing stiffness and the bearing stiffness in the transmission system,which is the inherent reason for the changed modal characteristics observed in the modal test and affects the vibration behavior of the gearbox consequently.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.42102313 and 52104125)the Fundamental Research Funds for the Central Universities(Grant No.B240201094).
文摘In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities.
文摘Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in these industries, it can also have multiple adverse environmental impacts. One such effect is flyrock, which poses risks to nearby machinery, and residential structures, and can even lead to injuries or fatalities. To optimize blasting efficiency as well as restrict side effects, prediction of the blast aftereffects is vital. Therefore, the present work focuses on using two machine learning methods to predict the velocity of flyrock in the open pit mine. To address this issue, a comprehensive dataset was gathered from the open pit mine. Then, Decision Tree and Random Forest algorithms were employed to predict flyrock velocity. The Random Forest model demonstrated superior performance compared to the Decision Tree model. Nonetheless, the performance of the Decision Tree model was deemed satisfactory, as evidenced by its coefficient of determination value of 0.83, mean squared error (MSE) of 4.2, and mean absolute percentage error (MAPE) of 5.6%. Considering these metrics, it is reasonable to conclude that tree-based algorithms can be effective in predicting flyrock velocity.
文摘转化医学（translational medicine）,也称转化研究（translational research）,是医学领域的新概念[1—2],强调把生物基础研究的最新成果快速有效地转化为临床医学技术的过程,即从实验室到病床（bench to bedside）再从病床到实验室（bedside to bench）的双向连续过程,简称为“B-to-B或B2B”。康复医学是有别于临床医学的以“功能障碍”患者为服务对象的学科[3]。
文摘针对一种硬质烟用滤棒的复合添加需求,设计一种烟用滤棒上下料机构。采用瞬态动力学分析方法,运用ANSYS Work Bench软件对滤棒上下料机构进行瞬态动力学仿真,并从结构动力学角度对该机构进行动态特性研究。分析结果显示,滤棒上下料机构的最大等效应力112.54 MPa,小于材料的许用应力。通过搭建实验平台进行试验,验证该滤棒上下料机构的合理性及稳定性。研究结果表明:滤棒上下料机构结构设计合理,取料成功率达到100%,能够满足工作要求。
基金provided by MULUniversidad Politecnica de Madrid
文摘The paper reviews the development of prediction formulas for the fragmentation from bench blasting.Much attention has been paid to the Kuz-Ram model,its development and errors,and the mean vs.median misunderstanding.The work by the US Bureau of Mines(USBM)and Chung and Katsabanis are also reviewed,as well as the two Julius Kruttschnitt Mineral Research Centre(JKMRC)models,i.e.the crush zone model(CZM)and the two-component model(TCM),which were developed to cope with the underestimation of blasting fines.The change brought by the Swebrec distribution and the associated Kuznetsov-Cunningham-Ouchterlony(KCO)model is described.Studying distribution-free fragment sizes xP for an arbitrary mass passing P led to the discovery of the fragmentation-energy fan,and with the help of dimensional analysis,to the new fragmentation prediction model xP-frag,which has much lower errors than those of the Kuz-Ram and CZM models.
