Linear switched reluctance motor(LSRM)and its applications in different industries have been an interesting research topic for the past few years.LSRMs have proved to be a suitable alternative in a variety of applicat...Linear switched reluctance motor(LSRM)and its applications in different industries have been an interesting research topic for the past few years.LSRMs have proved to be a suitable alternative in a variety of applications requiring linear motion.However,its use is not that popular which instigated an active interest in the evolution of newer LSRM configurations.Enhancement in its propulsion force along with the reduction in force ripples,weight,acoustic noise,and vibration have been the main objectives in recently proposed LSRM designs.In this paper,recently proposed LSRM designs are reviewed and analyzed.The paper presents a one-stop introduction and a complete update to the designs,both in terms of qualitative and quantitative parameters.In addition,it takes into account the challenges in the implementation of these designs.Based on a detailed comparison of these designs as presented in this paper,an appropriate design can be chosen for a given application.展开更多
BACKGROUND: Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke. OBJECTIVE: To observe the effect of percutaneous neuromuscular electric stimu...BACKGROUND: Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke. OBJECTIVE: To observe the effect of percutaneous neuromuscular electric stimulation (PNES) on difference in temperature of axilla and analyze the relationship between function of limbs and difference in temperature of axilla. DESIGN: Randomized grouping and controlled observation SETTING: Department of Neurology, General Hospital of Shenyang Military Area Command of Chinese PLA PARTICIPANTS: Sixty patients with ischemic stroke were selected from Neurological Department of General Hospital of Shenyang Military Area Command of Chinese PLA from January to June 2003. All cases were diagnosed with clinical diagnosis criteria of ischemic stroke established by the Fourth Chinese Classification of Cerebrovasular Disease and CT examination and received neuromuscular electric stimulation (NES). Patients were randomly divided into control group and treatment group with 30 in each group. METHODS: Control group: Patients received routinely neurological therapy. Treatment group: Except routine therapy, patients suffered from NES at 48 hours after hospitalization. NMT-91 NES equipment was used to stimulated injured limbs with low frequency once 30 minutes a day in total of 10 times a course, especially extensor muscle of upper limb and flexor muscle of lower limb. Prescription of hemiplegia was internally decided by equipment with the output frequency of 200 Hz. Intensity of electric output could cause muscle contraction. The therapy needed two or three courses. Temperature of bilateral axilla was measured every day to calculate the difference with the formula of (temperature of axilla on the injured side - temperature of axilla on the healthy side). Motor function of limbs was measured with FugI-Meyer Motor Assessment (FMA) during hospitalization and at 2 and 4 hours after hospitalization. Among 90 points, upper and lower limb function was 54, equilibrium function 10, sensory function 10, and motion of joint 16. The higher the scores were, the better the function was. Correlation of data was dealt with linear correlation analysis. MAIN OUTCOME MEASURES : Assessment and correlation between difference in temperature of axilla and motor function of injured limbs during hospitalization and at 2 and 4 weeks after hospitalization. RESULTS: All 60 patients with ischemic stroke were involved in the final analysis. ① Difference in temperature: Difference of 2 and 4 weeks after hospitalization was lower than that in control group and at just hospitalization [treatment group: (0.056±0.000), (0.024±0.003) ℃; control group: (0.250±0.001), (0.131 ±0.001)℃; hospitalization; (0.513±0.001) ℃, P 〈 0.05-0,01]. ② FMA scores: Scores of 2 and 4 weeks after hospitalization were higher than those in control group and at just hospitalization [treatment group; (43.50±15.09), (67.97 ±18.21) points; control group: (33.33 ±13.54), (40.87±19.34) points; hospitalization: (26.43 ±11.87) points, P 〈 0.05-0.01]. ③ Correlation: Difference in temperature of axilla was negative correlation with FMA scores (c=- -0.255 1, P 〈 0.05). CONCLUSION: ① PNES can accelerate recovery of limb function and decrease temperature of axilla of patients with ischemic stroke. ② The lower the difference in temperature is, the better the functional recovery is.展开更多
With the continuous development of society, the application standards for various related technical equipment in the coal mining industry are getting higher and higher. As one of the more commonly used equipment in th...With the continuous development of society, the application standards for various related technical equipment in the coal mining industry are getting higher and higher. As one of the more commonly used equipment in the coal mining industry, explosion-proof diesel engines continue to promote the normal operation of coal mines. However, at the same time, its existing problems are becoming more and more obvious. Only by studying these problems and determining the future development trend of explosion-proof diesel engines can we better promote their application in the coal mining industry. Therefore, this article will carry out specific research and analysis on explosion-proof diesel engines through the overview, application status, existing problems of explosion-proof diesel engines for coal mines, and future development trends of explosion-proof diesel engines for coal mines, hoping to provide better application and development of explosion-proof diesel engines with doing something about it.展开更多
This paper takes micro-nano motors and metamaterials as examples to introduce the basic concept and development of functional micro nano structures, and analyzes the application potential of the micro-nano structure d...This paper takes micro-nano motors and metamaterials as examples to introduce the basic concept and development of functional micro nano structures, and analyzes the application potential of the micro-nano structure design and manufacturing technology in the petroleum industry. The functional micro-nano structure is the structure and device with special functions prepared to achieve a specific goal. New functional micro-nano structures are classified into mobile type(e.g. micro-nano motors) and fixed type(e.g. metamaterials), and 3 D printing technology is a developed method of manufacturing. Combining the demand for exploration and development in oil and gas fields and the research status of intelligent micro-nano structures, we believe that there are 3 potential application directions:(1) The intelligent micro-nano structures represented by metamaterials and smart coatings can be applied to the oil recovery engineering technology and equipment to improve the stability and reliability of petroleum equipment.(2) The smart micro-nano robots represented by micro-motors and smart microspheres can be applied to the development of new materials for enhanced oil recovery, effectively improving the development efficiency of heavy oil, shale oil and other resources.(3) The intelligent structure manufacturing technology represented by 3 D printing technology can be applied to the field of microfluidics in reservoir fluids to guide the selection of mine flooding agents and improve the efficiency of mining.展开更多
This study investigates the potential of metal additives in acrylonitrile butadiene styrene(ABS)polymer fuel to enhance hybrid rocket motor(HRM)performance through computational analysis,Chemical Equilibrium with Appl...This study investigates the potential of metal additives in acrylonitrile butadiene styrene(ABS)polymer fuel to enhance hybrid rocket motor(HRM)performance through computational analysis,Chemical Equilibrium with Applications(CEA),software.ABS was selected as the base fuel due to its thermoplastic nature,which allows for the creation of complex fuel geometries through 3D printing,offering significant flexibility in fuel design.Hybrid rockets,which combine a solid fuel with a liquid oxidiser,offer advantages in terms of operational simplicity and safety.However,conventional polymer fuels often exhibit low regression rates and suboptimal combustion efficiencies.In this research,we evaluated a range of metal additives-aluminium(Al),boron(B),nickel(Ni),copper(Cu),and iron(Fe)-at chamber pressures ranging from 1 to 30 bar and oxidiser-to-fuel(O/F)ratios between 1.1 and 12,resulting in 1800 unique test conditions.The main performance parameters used to assess each formulation were characteristic velocity(C^(*))and adiabatic flame temperature.The results revealed that each test produced a different optimum O/F ratio,with most ratios falling between 4 and 6.The highest performance was achieved at a chamber pressure of 30 bar across all formulations.Among the additives,Al and B demonstrated significant potential for improved combustion performance with increasing metal loadings.In contrast,Fe,Cu,and Ni reached optimal performance at a minimum loading of 1%.Future work includes investigating B-Al metal composites as additives into the ABS base polymer fuel,and doing experimental validation tests where the metallised ABS polymer fuel is 3D printed.展开更多
Objective:To observe the clinical efficacy of subcutaneous row needling at the Foot Motor Sensory Area combined with point application therapy and its influence on defecation-related symptoms.Methods:Seventy eligible ...Objective:To observe the clinical efficacy of subcutaneous row needling at the Foot Motor Sensory Area combined with point application therapy and its influence on defecation-related symptoms.Methods:Seventy eligible patients with poststroke constipation were assigned to an observation group or a control group using the random number table method,with 35 patients in each group.The observation group received subcutaneous row needling at the Foot Motor Sensory Area combined with point application therapy,whereas the control group received lactulose oral solution.After treatment,the total effective rate and safety were compared between the two groups,and changes in the patient assessment of constipation symptom(PAC-SYM),stool form,and constipation symptom scores were observed.Results:The total effective rate was 87.9%in the observation group and 69.7%in the control group,and the difference was statistically significant(P<0.05).No obvious adverse reactions occurred in either group.After treatment,PAC-SYM and constipation symptom scores in both groups were lower than before treatment(P<0.05),with the observation group scoring lower than the control group(P<0.05).After treatment,the Bristol stool form scale(BSFS)score in both groups increased(P<0.05)and approached the score of normal stool form;the difference in the BSFS score between the two groups was not statistically significant(P>0.05).Conclusion:Compared to oral lactulose,subcutaneous insertion with row needling at the scalp Foot Motor Sensory Area combined with point application therapy can better improve poststroke constipation symptoms,shorten both the interval between bowel movements and the duration of each bowel movement,and reduce rectal and abdominal discomfort,with fewer adverse reactions and good safety.展开更多
There has been a growing interest in switched reluctance motor(SRM)ever since the development of thyristor in 1956.The most appealing feature of SRM which attracts researchers over these years is its simple structure ...There has been a growing interest in switched reluctance motor(SRM)ever since the development of thyristor in 1956.The most appealing feature of SRM which attracts researchers over these years is its simple structure that incorporates concentrated windings on the stator poles and plain laminations of ferromagnetic material as a rotor.Due to this attributes,advances are being made rapidly with the consideration that SRM can be used as an alternative to DC motors and permanent magnet motors.The objective of this paper is to present an overview of the recent developments and a prediction of possible future advancements in SR Drives.Brief history,importance,innovations in structure and control,along with practical application examples are all discussed here to give a more in-depth comprehension of the motor.展开更多
Rotor speed estimation for induction motors is a key problem in speed-sensorless motor drives. This paper performs nonlinear high gain observer design based on the full-order model of the induction motor. Such an effo...Rotor speed estimation for induction motors is a key problem in speed-sensorless motor drives. This paper performs nonlinear high gain observer design based on the full-order model of the induction motor. Such an effort appears nontrivial due to the fact that the full-model at best admits locally a non-triangular observable form(NTOF), and its analytical representation in the NTOF can not be obtained. This paper proposes an approximate high gain estimation algorithm, which enjoys a constructive design, ease of tuning, and improved speed estimation and tracking performance. Experiments demonstrate the effectiveness of the proposed algorithm.展开更多
Objective:To study the effective value of introducing the concept of early oral exercise in the process of nursing intervention for preterm infants in the neonatal intensive care unit(NICU).Methods:96 cases of preterm...Objective:To study the effective value of introducing the concept of early oral exercise in the process of nursing intervention for preterm infants in the neonatal intensive care unit(NICU).Methods:96 cases of preterm infants diagnosed from January 2022 to August 2022 were selected and randomly divided into two groups:the general practice group(general nursing intervention),and the early practice group(early oral exercise intervention),and the effect of intervention on preterm infants in the two groups was observed.Results:After nursing care,the mean value of the non-nutritive sucking ability assessment(76.54±5.82),the mean value of the intellectual development degree assessment(104.57±8.45),the mean value of the psychomotor development degree assessment(102.33±6.74),and the mean value of behavioral neural reflexes ability assessment(38.71±2.40)in the early practice group were better than that as compared to the general practice group(P<0.05);the mean value of oral feeding start time of preterm infants in the early practice group(35.42±7.63)weeks,the mean value of all oral feeding time(34.12±5.28)weeks,and the mean time of hospital intervention(15.33±4.25)days were lesser than compared to those of the general practice group at 37.4±5.82 weeks,37.46±3.55 weeks,and 20.46±2.91 days,respectively(P<0.05);the rate of adverse reactions in preterm infants in the early practice group significantly lower than that of the general practice group(P<0.05).Conclusion:The introduction of the concept of early oral exercise intervention among NICU nurses improved the feeding effect,sucking ability of preterm infants,and intellectual development.Hence,early oral motor care should be popularized.展开更多
基金Authors thank MANIT Bhopal and Ministry of Education,India for extending financial support for the research work.
文摘Linear switched reluctance motor(LSRM)and its applications in different industries have been an interesting research topic for the past few years.LSRMs have proved to be a suitable alternative in a variety of applications requiring linear motion.However,its use is not that popular which instigated an active interest in the evolution of newer LSRM configurations.Enhancement in its propulsion force along with the reduction in force ripples,weight,acoustic noise,and vibration have been the main objectives in recently proposed LSRM designs.In this paper,recently proposed LSRM designs are reviewed and analyzed.The paper presents a one-stop introduction and a complete update to the designs,both in terms of qualitative and quantitative parameters.In addition,it takes into account the challenges in the implementation of these designs.Based on a detailed comparison of these designs as presented in this paper,an appropriate design can be chosen for a given application.
基金a grant from Military Tenth Five-Year Key Research Project Foundation, No. mymjzyy 010
文摘BACKGROUND: Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke. OBJECTIVE: To observe the effect of percutaneous neuromuscular electric stimulation (PNES) on difference in temperature of axilla and analyze the relationship between function of limbs and difference in temperature of axilla. DESIGN: Randomized grouping and controlled observation SETTING: Department of Neurology, General Hospital of Shenyang Military Area Command of Chinese PLA PARTICIPANTS: Sixty patients with ischemic stroke were selected from Neurological Department of General Hospital of Shenyang Military Area Command of Chinese PLA from January to June 2003. All cases were diagnosed with clinical diagnosis criteria of ischemic stroke established by the Fourth Chinese Classification of Cerebrovasular Disease and CT examination and received neuromuscular electric stimulation (NES). Patients were randomly divided into control group and treatment group with 30 in each group. METHODS: Control group: Patients received routinely neurological therapy. Treatment group: Except routine therapy, patients suffered from NES at 48 hours after hospitalization. NMT-91 NES equipment was used to stimulated injured limbs with low frequency once 30 minutes a day in total of 10 times a course, especially extensor muscle of upper limb and flexor muscle of lower limb. Prescription of hemiplegia was internally decided by equipment with the output frequency of 200 Hz. Intensity of electric output could cause muscle contraction. The therapy needed two or three courses. Temperature of bilateral axilla was measured every day to calculate the difference with the formula of (temperature of axilla on the injured side - temperature of axilla on the healthy side). Motor function of limbs was measured with FugI-Meyer Motor Assessment (FMA) during hospitalization and at 2 and 4 hours after hospitalization. Among 90 points, upper and lower limb function was 54, equilibrium function 10, sensory function 10, and motion of joint 16. The higher the scores were, the better the function was. Correlation of data was dealt with linear correlation analysis. MAIN OUTCOME MEASURES : Assessment and correlation between difference in temperature of axilla and motor function of injured limbs during hospitalization and at 2 and 4 weeks after hospitalization. RESULTS: All 60 patients with ischemic stroke were involved in the final analysis. ① Difference in temperature: Difference of 2 and 4 weeks after hospitalization was lower than that in control group and at just hospitalization [treatment group: (0.056±0.000), (0.024±0.003) ℃; control group: (0.250±0.001), (0.131 ±0.001)℃; hospitalization; (0.513±0.001) ℃, P 〈 0.05-0,01]. ② FMA scores: Scores of 2 and 4 weeks after hospitalization were higher than those in control group and at just hospitalization [treatment group; (43.50±15.09), (67.97 ±18.21) points; control group: (33.33 ±13.54), (40.87±19.34) points; hospitalization: (26.43 ±11.87) points, P 〈 0.05-0.01]. ③ Correlation: Difference in temperature of axilla was negative correlation with FMA scores (c=- -0.255 1, P 〈 0.05). CONCLUSION: ① PNES can accelerate recovery of limb function and decrease temperature of axilla of patients with ischemic stroke. ② The lower the difference in temperature is, the better the functional recovery is.
文摘With the continuous development of society, the application standards for various related technical equipment in the coal mining industry are getting higher and higher. As one of the more commonly used equipment in the coal mining industry, explosion-proof diesel engines continue to promote the normal operation of coal mines. However, at the same time, its existing problems are becoming more and more obvious. Only by studying these problems and determining the future development trend of explosion-proof diesel engines can we better promote their application in the coal mining industry. Therefore, this article will carry out specific research and analysis on explosion-proof diesel engines through the overview, application status, existing problems of explosion-proof diesel engines for coal mines, and future development trends of explosion-proof diesel engines for coal mines, hoping to provide better application and development of explosion-proof diesel engines with doing something about it.
基金Supported by the National Natural Science Foundation of China(41602159)
文摘This paper takes micro-nano motors and metamaterials as examples to introduce the basic concept and development of functional micro nano structures, and analyzes the application potential of the micro-nano structure design and manufacturing technology in the petroleum industry. The functional micro-nano structure is the structure and device with special functions prepared to achieve a specific goal. New functional micro-nano structures are classified into mobile type(e.g. micro-nano motors) and fixed type(e.g. metamaterials), and 3 D printing technology is a developed method of manufacturing. Combining the demand for exploration and development in oil and gas fields and the research status of intelligent micro-nano structures, we believe that there are 3 potential application directions:(1) The intelligent micro-nano structures represented by metamaterials and smart coatings can be applied to the oil recovery engineering technology and equipment to improve the stability and reliability of petroleum equipment.(2) The smart micro-nano robots represented by micro-motors and smart microspheres can be applied to the development of new materials for enhanced oil recovery, effectively improving the development efficiency of heavy oil, shale oil and other resources.(3) The intelligent structure manufacturing technology represented by 3 D printing technology can be applied to the field of microfluidics in reservoir fluids to guide the selection of mine flooding agents and improve the efficiency of mining.
文摘This study investigates the potential of metal additives in acrylonitrile butadiene styrene(ABS)polymer fuel to enhance hybrid rocket motor(HRM)performance through computational analysis,Chemical Equilibrium with Applications(CEA),software.ABS was selected as the base fuel due to its thermoplastic nature,which allows for the creation of complex fuel geometries through 3D printing,offering significant flexibility in fuel design.Hybrid rockets,which combine a solid fuel with a liquid oxidiser,offer advantages in terms of operational simplicity and safety.However,conventional polymer fuels often exhibit low regression rates and suboptimal combustion efficiencies.In this research,we evaluated a range of metal additives-aluminium(Al),boron(B),nickel(Ni),copper(Cu),and iron(Fe)-at chamber pressures ranging from 1 to 30 bar and oxidiser-to-fuel(O/F)ratios between 1.1 and 12,resulting in 1800 unique test conditions.The main performance parameters used to assess each formulation were characteristic velocity(C^(*))and adiabatic flame temperature.The results revealed that each test produced a different optimum O/F ratio,with most ratios falling between 4 and 6.The highest performance was achieved at a chamber pressure of 30 bar across all formulations.Among the additives,Al and B demonstrated significant potential for improved combustion performance with increasing metal loadings.In contrast,Fe,Cu,and Ni reached optimal performance at a minimum loading of 1%.Future work includes investigating B-Al metal composites as additives into the ABS base polymer fuel,and doing experimental validation tests where the metallised ABS polymer fuel is 3D printed.
文摘Objective:To observe the clinical efficacy of subcutaneous row needling at the Foot Motor Sensory Area combined with point application therapy and its influence on defecation-related symptoms.Methods:Seventy eligible patients with poststroke constipation were assigned to an observation group or a control group using the random number table method,with 35 patients in each group.The observation group received subcutaneous row needling at the Foot Motor Sensory Area combined with point application therapy,whereas the control group received lactulose oral solution.After treatment,the total effective rate and safety were compared between the two groups,and changes in the patient assessment of constipation symptom(PAC-SYM),stool form,and constipation symptom scores were observed.Results:The total effective rate was 87.9%in the observation group and 69.7%in the control group,and the difference was statistically significant(P<0.05).No obvious adverse reactions occurred in either group.After treatment,PAC-SYM and constipation symptom scores in both groups were lower than before treatment(P<0.05),with the observation group scoring lower than the control group(P<0.05).After treatment,the Bristol stool form scale(BSFS)score in both groups increased(P<0.05)and approached the score of normal stool form;the difference in the BSFS score between the two groups was not statistically significant(P>0.05).Conclusion:Compared to oral lactulose,subcutaneous insertion with row needling at the scalp Foot Motor Sensory Area combined with point application therapy can better improve poststroke constipation symptoms,shorten both the interval between bowel movements and the duration of each bowel movement,and reduce rectal and abdominal discomfort,with fewer adverse reactions and good safety.
基金This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(2018R1D1A1B07043735)。
文摘There has been a growing interest in switched reluctance motor(SRM)ever since the development of thyristor in 1956.The most appealing feature of SRM which attracts researchers over these years is its simple structure that incorporates concentrated windings on the stator poles and plain laminations of ferromagnetic material as a rotor.Due to this attributes,advances are being made rapidly with the consideration that SRM can be used as an alternative to DC motors and permanent magnet motors.The objective of this paper is to present an overview of the recent developments and a prediction of possible future advancements in SR Drives.Brief history,importance,innovations in structure and control,along with practical application examples are all discussed here to give a more in-depth comprehension of the motor.
文摘Rotor speed estimation for induction motors is a key problem in speed-sensorless motor drives. This paper performs nonlinear high gain observer design based on the full-order model of the induction motor. Such an effort appears nontrivial due to the fact that the full-model at best admits locally a non-triangular observable form(NTOF), and its analytical representation in the NTOF can not be obtained. This paper proposes an approximate high gain estimation algorithm, which enjoys a constructive design, ease of tuning, and improved speed estimation and tracking performance. Experiments demonstrate the effectiveness of the proposed algorithm.
文摘Objective:To study the effective value of introducing the concept of early oral exercise in the process of nursing intervention for preterm infants in the neonatal intensive care unit(NICU).Methods:96 cases of preterm infants diagnosed from January 2022 to August 2022 were selected and randomly divided into two groups:the general practice group(general nursing intervention),and the early practice group(early oral exercise intervention),and the effect of intervention on preterm infants in the two groups was observed.Results:After nursing care,the mean value of the non-nutritive sucking ability assessment(76.54±5.82),the mean value of the intellectual development degree assessment(104.57±8.45),the mean value of the psychomotor development degree assessment(102.33±6.74),and the mean value of behavioral neural reflexes ability assessment(38.71±2.40)in the early practice group were better than that as compared to the general practice group(P<0.05);the mean value of oral feeding start time of preterm infants in the early practice group(35.42±7.63)weeks,the mean value of all oral feeding time(34.12±5.28)weeks,and the mean time of hospital intervention(15.33±4.25)days were lesser than compared to those of the general practice group at 37.4±5.82 weeks,37.46±3.55 weeks,and 20.46±2.91 days,respectively(P<0.05);the rate of adverse reactions in preterm infants in the early practice group significantly lower than that of the general practice group(P<0.05).Conclusion:The introduction of the concept of early oral exercise intervention among NICU nurses improved the feeding effect,sucking ability of preterm infants,and intellectual development.Hence,early oral motor care should be popularized.