Objective:to study the effect of automatic tube current modulation on abdominal CT image quality and radiation dose. Methods: a total of 70 patients who underwent abdominal CT examination in our hospital from August 2...Objective:to study the effect of automatic tube current modulation on abdominal CT image quality and radiation dose. Methods: a total of 70 patients who underwent abdominal CT examination in our hospital from August 2019 to August 2020 were collected and divided into control group (35 cases) and study group (35 cases) according to the random number table. CT scan was performed in the control group according to the conventional parameters, while CT scan was performed in the research group using automatic tube current modulation technology. The CT image quality and radiation dose of patients in the two groups were compared. Results: the image quality of the study group was better than that of the control group (P < 0.05). When NI ≥8, the radiation dose in the study group was lower than that in the control group (P < 0.05). Conclusion Automatic tube current modulation technique can obtain better image quality in CT detection, and has significant significance in reducing radiation dose. It is worthy of affirmation, praise and application.展开更多
A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when...A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when the injection current of the distributed feedback laser is 100mA at 25℃. The side mode suppression ratio is over 50 dB. A 32Gb/s eye diagram is measured with a 3.SVpp nonreturn-to-zero pseudorandom modulation signal at -2.3 V bias. A clearly opening eyediagram with a dynamic extinction ratio of 8.01 dB is obtained.展开更多
The COVID-19 pandemic has caused higher educational institutions around the world to close campus-based activities and move to online delivery.The aim of this paper is to present the case of Global College of Engineer...The COVID-19 pandemic has caused higher educational institutions around the world to close campus-based activities and move to online delivery.The aim of this paper is to present the case of Global College of Engineering and Technology(GCET)and how its practices including teaching,students/staff support,assessments,and exam policies were affected.The paper investigates the mediating role of no detriment policy impact on students’result along with the challenges faced by the higher educational institution,recommendations and suggestions.The investigation concludes that the strategies adopted for online delivery,student support,assessments and exam policies have helped students to effectively cope with the teaching and learning challenges posed by the COVID-19 pandemic without affecting their academic results.The study shows that 99%of students were able to maintain the same or better level of performance during the 1st COVID-19 semester.One percent of students had shown a slight decrease in their performance(about 1%–2%)with respect to their overall marks pre-COVID-19.The no detriment policy has succoured those 1%of the students to maintain their overall performance to what it used to be pre-COVID-19 pandemic.Finally,the paper provides the list of challenges and suggestions for smooth conduction of online education.展开更多
With the continuous development of science and technolog ies in China,radiotherapy technology in medical field has been very significant ly developing,and intensity modulated radiation therapy(IMRT)technology has been...With the continuous development of science and technolog ies in China,radiotherapy technology in medical field has been very significant ly developing,and intensity modulated radiation therapy(IMRT)technology has been the most widely used.This paper first introduces the components and types of two-dimensional matrix detector,two-dimensional ionization chamber matrix detector and two-dimensional semiconductor matrix detector,then analyzes the dosimetric characteristics of the two-dimensional matrix detector.In the end,the various applications of the two-dimensional matrix detector are analyzed and discussed in detail.The paper aims to promote the two-dimensional matrix detector’s development in the field of radiotherapy in China.展开更多
Traditional gyrocompasses,while capable of providing autonomous directional guidance and path correction,face limitations in widespread applications due to their large size,making them unsuitable for compact devices.M...Traditional gyrocompasses,while capable of providing autonomous directional guidance and path correction,face limitations in widespread applications due to their large size,making them unsuitable for compact devices.Microelectromechanical system(MEMS)gyrocompasses offer a promising alternative for miniaturization.However,current MEMS gyrocompasses require the integration of motor rotation modulation technology to achieve high-precision north-finding,whereas conventional motors in previous research introduce large volume and residual magnetism,thus undermining their size advantage.Here,we innovatively propose a miniature MEMS gyrocompass based on a MEMS traveling-wave micromotor,featuring the first integration of a chip-scale rotational actuator and combined with a precise multi-position braking control system,enabling high accuracy and fast north-finding.The proposed gyrocompass made significant advancements,reducing its size to 50×42.5×24.5 mm^(3)and achieving an azimuth accuracy of 0.199°within 2 min,which is half the volume of the smallest existing similar devices while offering twice the performance.These improvements indicate that the proposed gyrocompass is suitable for applications in indoor industrial robotics,autonomous driving,and other related fields requiring precise directional guidance.展开更多
Microfluidic modulation spectroscopy(MMS)has been recognised as a novel technology for producing high quality and reproducible data at a wide concentration range to characterise protein structure.In this study,the use...Microfluidic modulation spectroscopy(MMS)has been recognised as a novel technology for producing high quality and reproducible data at a wide concentration range to characterise protein structure.In this study,the use of MMS for food applications was explored through the structural analysis of pea protein,whey protein,and pea/whey protein complexes prepared by transglutaminase cross-linking.MMS generated reproducible data with>99.5%repeatability in all protein samples.The cross-linking seemed to alter the structure of whey protein with isopeptide and hydrogen bond formation,more significantly than that of pea protein.The larger secondary and tertiary structural changes were observed with higher whey protein content in cross-linked pea/whey protein complex,which eventually increased the surface hydrophobicity.According to the second derivatives analysis by MMS,β-sheet and random coil increased andβ-turn decreased in the pea protein,whereasα-helix,β-sheet,andβ-turn decreased and random coil increased in the whey protein after cross-linking.In the pea/whey protein complex,β-turn shifted toβ-sheet due to cross-linking.There are some discrepancies between the relative secondary structure contents obtained from MMS data compared to the data acquired from circular dichroism.However,MMS has the considerable advantage of being able to directly measure original samples without significant dilution as required for circular dichroism measurements.This study provides evidence that MMS technology could be a robust technique to quantify the secondary structures of typical proteins in food with high reliability.展开更多
A low power and low voltage∑△analog-to-digital modulator is realized with digital CMOS technology, which is due to full compensated depletion mode capacitors.Compared with mixed signal technology,this type of modula...A low power and low voltage∑△analog-to-digital modulator is realized with digital CMOS technology, which is due to full compensated depletion mode capacitors.Compared with mixed signal technology,this type of modulator is more compatible for pure digital applications.A pseudo-two-stage class-AB OTA is used in switchedcapacitor integrators for low voltage and low power.The modulator is realized in standard SMIC 0.18μm 1P6M digital CMOS technology.Measured results show that with 1.2 V supply voltage and a 6 MHz sample clock,the dynamic range of the modulator is 84 dB and the total power dissipation is 2460μW.展开更多
文摘Objective:to study the effect of automatic tube current modulation on abdominal CT image quality and radiation dose. Methods: a total of 70 patients who underwent abdominal CT examination in our hospital from August 2019 to August 2020 were collected and divided into control group (35 cases) and study group (35 cases) according to the random number table. CT scan was performed in the control group according to the conventional parameters, while CT scan was performed in the research group using automatic tube current modulation technology. The CT image quality and radiation dose of patients in the two groups were compared. Results: the image quality of the study group was better than that of the control group (P < 0.05). When NI ≥8, the radiation dose in the study group was lower than that in the control group (P < 0.05). Conclusion Automatic tube current modulation technique can obtain better image quality in CT detection, and has significant significance in reducing radiation dose. It is worthy of affirmation, praise and application.
基金Supported by the National High-Technology Research and Development Program of China under Grant Nos 2011AA010303and 2012AA012203the National Basic Research Program of China under Grant No 2011CB301702the National Natural Science Foundation of China under Grant Nos 61321063 and 6132010601
文摘A 32 Gb/s monolithically integrated electroabsorption modulated laser is fabricated by selective area growth technology. The threshold current of the device is below 13mA. The output power exceeds 10mW at 0V bias when the injection current of the distributed feedback laser is 100mA at 25℃. The side mode suppression ratio is over 50 dB. A 32Gb/s eye diagram is measured with a 3.SVpp nonreturn-to-zero pseudorandom modulation signal at -2.3 V bias. A clearly opening eyediagram with a dynamic extinction ratio of 8.01 dB is obtained.
基金supported by Global College of Engineering and Technology(GCET).
文摘The COVID-19 pandemic has caused higher educational institutions around the world to close campus-based activities and move to online delivery.The aim of this paper is to present the case of Global College of Engineering and Technology(GCET)and how its practices including teaching,students/staff support,assessments,and exam policies were affected.The paper investigates the mediating role of no detriment policy impact on students’result along with the challenges faced by the higher educational institution,recommendations and suggestions.The investigation concludes that the strategies adopted for online delivery,student support,assessments and exam policies have helped students to effectively cope with the teaching and learning challenges posed by the COVID-19 pandemic without affecting their academic results.The study shows that 99%of students were able to maintain the same or better level of performance during the 1st COVID-19 semester.One percent of students had shown a slight decrease in their performance(about 1%–2%)with respect to their overall marks pre-COVID-19.The no detriment policy has succoured those 1%of the students to maintain their overall performance to what it used to be pre-COVID-19 pandemic.Finally,the paper provides the list of challenges and suggestions for smooth conduction of online education.
文摘With the continuous development of science and technolog ies in China,radiotherapy technology in medical field has been very significant ly developing,and intensity modulated radiation therapy(IMRT)technology has been the most widely used.This paper first introduces the components and types of two-dimensional matrix detector,two-dimensional ionization chamber matrix detector and two-dimensional semiconductor matrix detector,then analyzes the dosimetric characteristics of the two-dimensional matrix detector.In the end,the various applications of the two-dimensional matrix detector are analyzed and discussed in detail.The paper aims to promote the two-dimensional matrix detector’s development in the field of radiotherapy in China.
基金supported by the National Basic Research Foundation(Grant No.5140508A0501).
文摘Traditional gyrocompasses,while capable of providing autonomous directional guidance and path correction,face limitations in widespread applications due to their large size,making them unsuitable for compact devices.Microelectromechanical system(MEMS)gyrocompasses offer a promising alternative for miniaturization.However,current MEMS gyrocompasses require the integration of motor rotation modulation technology to achieve high-precision north-finding,whereas conventional motors in previous research introduce large volume and residual magnetism,thus undermining their size advantage.Here,we innovatively propose a miniature MEMS gyrocompass based on a MEMS traveling-wave micromotor,featuring the first integration of a chip-scale rotational actuator and combined with a precise multi-position braking control system,enabling high accuracy and fast north-finding.The proposed gyrocompass made significant advancements,reducing its size to 50×42.5×24.5 mm^(3)and achieving an azimuth accuracy of 0.199°within 2 min,which is half the volume of the smallest existing similar devices while offering twice the performance.These improvements indicate that the proposed gyrocompass is suitable for applications in indoor industrial robotics,autonomous driving,and other related fields requiring precise directional guidance.
基金supported by ARC Discovery grant(DP200100642)supported by a PhD scholarship from the UNSW Sydney.
文摘Microfluidic modulation spectroscopy(MMS)has been recognised as a novel technology for producing high quality and reproducible data at a wide concentration range to characterise protein structure.In this study,the use of MMS for food applications was explored through the structural analysis of pea protein,whey protein,and pea/whey protein complexes prepared by transglutaminase cross-linking.MMS generated reproducible data with>99.5%repeatability in all protein samples.The cross-linking seemed to alter the structure of whey protein with isopeptide and hydrogen bond formation,more significantly than that of pea protein.The larger secondary and tertiary structural changes were observed with higher whey protein content in cross-linked pea/whey protein complex,which eventually increased the surface hydrophobicity.According to the second derivatives analysis by MMS,β-sheet and random coil increased andβ-turn decreased in the pea protein,whereasα-helix,β-sheet,andβ-turn decreased and random coil increased in the whey protein after cross-linking.In the pea/whey protein complex,β-turn shifted toβ-sheet due to cross-linking.There are some discrepancies between the relative secondary structure contents obtained from MMS data compared to the data acquired from circular dichroism.However,MMS has the considerable advantage of being able to directly measure original samples without significant dilution as required for circular dichroism measurements.This study provides evidence that MMS technology could be a robust technique to quantify the secondary structures of typical proteins in food with high reliability.
基金supported by the National Natural Science Foundation of China(No.60236020)the Scientific Research Common Program of Beijing Municipal Commission of Education(No.KM201211232018)the Natural Science Foundation of Beijing City(No.4112029)
文摘A low power and low voltage∑△analog-to-digital modulator is realized with digital CMOS technology, which is due to full compensated depletion mode capacitors.Compared with mixed signal technology,this type of modulator is more compatible for pure digital applications.A pseudo-two-stage class-AB OTA is used in switchedcapacitor integrators for low voltage and low power.The modulator is realized in standard SMIC 0.18μm 1P6M digital CMOS technology.Measured results show that with 1.2 V supply voltage and a 6 MHz sample clock,the dynamic range of the modulator is 84 dB and the total power dissipation is 2460μW.
