Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the ...Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the importance of protecting our world for future generations [1]. To provide the protection of our planet, we should explain Earth’s environmental challenges to the best of our knowledge in frames of contemporary Geophysics. This paper gives a short overview of the developed Hypersphere World-Universe Model (WUM) and pay particular attention to the principal role of Dark Matter (DM) in the Earth’s life. In this manuscript, we discuss different aspects of the Earth: a condition of Young Earth before the Beginning of life on It;Internal Structure;“The 660-km Boundary” that we named Geomagma;Random Variations of Earth’s Rotational Speed on a daily basis;Origin of Moon;Expanding Earth;Internal Heating;Faint Young Sun paradox;Geocorona and Planetary Coronas;High-Energy Atmospheric Physics. WUM proposed principally different ways to solve the problems of Internal Heating, Origin of the Moon, and Faint Young Sun paradox based on DM core of the Earth. The Model revealed the fact that the Sun Activity causes the Geomagma Activity and, as a consequence, Random Variations of Earth’s Rotational Speed by the varying Sun’s magnetic field.展开更多
This study aims to evaluate inter-fractional set-up errors in patients treated with distinct immobilization equipment (thermoplastic mask, knee-fix and feet-fix, wing board and vac-lok) for four anatomical regions inc...This study aims to evaluate inter-fractional set-up errors in patients treated with distinct immobilization equipment (thermoplastic mask, knee-fix and feet-fix, wing board and vac-lok) for four anatomical regions including brain, head and neck (HN), thorax and pelvis. Data of randomly selected 140 patients who were treated for four anatomical regions were obtained using Hi-Art Helical Tomotherapy (HT) system. Pre-treatment planning was based on automatic registration readings of computed tomography (CT) and mega-voltage computed tomography (MVCT) on a daily basis. Distinct immobilization equipment was used for varying anatomical regions. Individual mean set-up error (M), systematic error (Σ), and random error (σ) values were calculated through daily translational and rotational deviation values. The size of translational, systematic and random error was 1.31 - 4.93 mm for brain, 2.28 - 4.88 mm for HN, 4.04 - 9.90 mm for thorax, and 6.34 - 14.68 mm for pelvis. Rotational values were as follows: 0.06° - 0.73° for brain, 0.42° - 0.6° for HN, 0.48° - 1.14° for thorax and 0.65° - 1.05° for pelvis. The highest translational, systematic and random error value was obtained from the pelvic regional. The highest standard and random error value in pitch and roll was produced in the rotational direction of the pelvis (0.05° and 0.71°), while the highest error value in yaw was (1.14°) produced from thorax. Inter-fractional set-up errors were most commonly produced in the pelvis, followed by thorax. Our study results suggest that the highest systematic and random errors are found for thorax and pelvis. Distinct immobilization equipment was important in these results. Safety margins around the clinical target volume (CTV) are changeable for different anatomical regions. A future work could be developed to new equipment for immobilization because of the reduced margins CTV.展开更多
We use the method of wavelet transform to analyze the time series of the Earth＇s rotation rate of the EOP （IERS） C04. The result shows that the seasonal （annual and semiannual） variation of the length-of-day （LO...We use the method of wavelet transform to analyze the time series of the Earth＇s rotation rate of the EOP （IERS） C04. The result shows that the seasonal （annual and semiannual） variation of the length-of-day （LOD） has temporal variability in its period length and amplitude. During 1965.0-2001.0, the periods of the semiannual and annual components varied mainly from 175-day to 190-day and from 360-day to 370-day, respectively; while their amplitudes varied by more than 0.2 ms and 0.1 ms, respectively. Analyzing the axial component of atmospheric angular momentum （AAM） during this period, we have found that time-variations of period lengths and amplitudes also exist in the seasonal oscillations of the axial AAM and are in good consistency with those of the seasonal LOD change. The time variation of the axial AAM can explain largely the change of the LOD on seasonal scales.展开更多
It is well known that a variation in the direction of Earth’s rotation axis is a real astronomical phenomenon, named nutation. It is interesting if a variation of this axis can take place only in intensity, in the si...It is well known that a variation in the direction of Earth’s rotation axis is a real astronomical phenomenon, named nutation. It is interesting if a variation of this axis can take place only in intensity, in the simplest theoretical case of only two rigid body dynamics. This paper presents two positions of the Moon during its monthly orbit, where a sudden variation of Earth’s rotation axis in intensity can take place. The duration of this phenomenon is limited in time, maybe an instant or a day, and then a vortex can appear.展开更多
Although the Japanese records of central or near central solar eclipses (i.e. the total, annular and total-annular eclipses) are not very old, so long as their documents definitely recording the observational place, d...Although the Japanese records of central or near central solar eclipses (i.e. the total, annular and total-annular eclipses) are not very old, so long as their documents definitely recording the observational place, date and phenomenon of the eclipse or the parameters can be defined through some textual researches even if展开更多
In the study of variation of the earth’s rotation based on the records of some ancientastronomical events, the timing records of ancient astronomical events and phenomena, suchas solar and lunar eclises and lunar occ...In the study of variation of the earth’s rotation based on the records of some ancientastronomical events, the timing records of ancient astronomical events and phenomena, suchas solar and lunar eclises and lunar occultation, are important components of the data.The reliable records, especially those from the countries and regions with advanced an-cient astronomy and timing technology, contain valuable information on the variation展开更多
A novel wrist-inspired soft actuator,which is driven by a magneto-pneumatic hybrid system and based on a Kresling origami unit,is proposed.The geometric model,kinematic analysis model,and quasistatic analysis model of...A novel wrist-inspired soft actuator,which is driven by a magneto-pneumatic hybrid system and based on a Kresling origami unit,is proposed.The geometric model,kinematic analysis model,and quasistatic analysis model of the Kresling origami unit are presented.A key focus is on the formulation and investigation of the variation in rotation angle using the kinematic analysis model.A wrist-inspired soft actuator is designed,and its quasistatic characteristics are validated through various experiments.The paper proposes an innovative magneto-pneumatic hybrid actuation method,capable of achieving bidirectional torsion.This actuation method is experimentally validated,demonstrating the actuator's ability to maintain 3 steady states and its capability for bidirectional torsion deformation.Furthermore,the paper highlights the potential of the Kresling origami unit in designing soft actuators capable of achieving large rotation angles.For instance,an actuator with 6 sides(n=6)is shown to achieve a rotation angle of 239.5°,and its rotation ratio exceeds 277°,about twice the largest one reported in other literature.The actuator offers a practical and effective solution for bidirectional torsion deformation in soft robotic applications.展开更多
文摘Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the importance of protecting our world for future generations [1]. To provide the protection of our planet, we should explain Earth’s environmental challenges to the best of our knowledge in frames of contemporary Geophysics. This paper gives a short overview of the developed Hypersphere World-Universe Model (WUM) and pay particular attention to the principal role of Dark Matter (DM) in the Earth’s life. In this manuscript, we discuss different aspects of the Earth: a condition of Young Earth before the Beginning of life on It;Internal Structure;“The 660-km Boundary” that we named Geomagma;Random Variations of Earth’s Rotational Speed on a daily basis;Origin of Moon;Expanding Earth;Internal Heating;Faint Young Sun paradox;Geocorona and Planetary Coronas;High-Energy Atmospheric Physics. WUM proposed principally different ways to solve the problems of Internal Heating, Origin of the Moon, and Faint Young Sun paradox based on DM core of the Earth. The Model revealed the fact that the Sun Activity causes the Geomagma Activity and, as a consequence, Random Variations of Earth’s Rotational Speed by the varying Sun’s magnetic field.
文摘This study aims to evaluate inter-fractional set-up errors in patients treated with distinct immobilization equipment (thermoplastic mask, knee-fix and feet-fix, wing board and vac-lok) for four anatomical regions including brain, head and neck (HN), thorax and pelvis. Data of randomly selected 140 patients who were treated for four anatomical regions were obtained using Hi-Art Helical Tomotherapy (HT) system. Pre-treatment planning was based on automatic registration readings of computed tomography (CT) and mega-voltage computed tomography (MVCT) on a daily basis. Distinct immobilization equipment was used for varying anatomical regions. Individual mean set-up error (M), systematic error (Σ), and random error (σ) values were calculated through daily translational and rotational deviation values. The size of translational, systematic and random error was 1.31 - 4.93 mm for brain, 2.28 - 4.88 mm for HN, 4.04 - 9.90 mm for thorax, and 6.34 - 14.68 mm for pelvis. Rotational values were as follows: 0.06° - 0.73° for brain, 0.42° - 0.6° for HN, 0.48° - 1.14° for thorax and 0.65° - 1.05° for pelvis. The highest translational, systematic and random error value was obtained from the pelvic regional. The highest standard and random error value in pitch and roll was produced in the rotational direction of the pelvis (0.05° and 0.71°), while the highest error value in yaw was (1.14°) produced from thorax. Inter-fractional set-up errors were most commonly produced in the pelvis, followed by thorax. Our study results suggest that the highest systematic and random errors are found for thorax and pelvis. Distinct immobilization equipment was important in these results. Safety margins around the clinical target volume (CTV) are changeable for different anatomical regions. A future work could be developed to new equipment for immobilization because of the reduced margins CTV.
基金Supported by the National Natural Science Foundation of China
文摘We use the method of wavelet transform to analyze the time series of the Earth＇s rotation rate of the EOP （IERS） C04. The result shows that the seasonal （annual and semiannual） variation of the length-of-day （LOD） has temporal variability in its period length and amplitude. During 1965.0-2001.0, the periods of the semiannual and annual components varied mainly from 175-day to 190-day and from 360-day to 370-day, respectively; while their amplitudes varied by more than 0.2 ms and 0.1 ms, respectively. Analyzing the axial component of atmospheric angular momentum （AAM） during this period, we have found that time-variations of period lengths and amplitudes also exist in the seasonal oscillations of the axial AAM and are in good consistency with those of the seasonal LOD change. The time variation of the axial AAM can explain largely the change of the LOD on seasonal scales.
文摘It is well known that a variation in the direction of Earth’s rotation axis is a real astronomical phenomenon, named nutation. It is interesting if a variation of this axis can take place only in intensity, in the simplest theoretical case of only two rigid body dynamics. This paper presents two positions of the Moon during its monthly orbit, where a sudden variation of Earth’s rotation axis in intensity can take place. The duration of this phenomenon is limited in time, maybe an instant or a day, and then a vortex can appear.
文摘Although the Japanese records of central or near central solar eclipses (i.e. the total, annular and total-annular eclipses) are not very old, so long as their documents definitely recording the observational place, date and phenomenon of the eclipse or the parameters can be defined through some textual researches even if
文摘In the study of variation of the earth’s rotation based on the records of some ancientastronomical events, the timing records of ancient astronomical events and phenomena, suchas solar and lunar eclises and lunar occultation, are important components of the data.The reliable records, especially those from the countries and regions with advanced an-cient astronomy and timing technology, contain valuable information on the variation
基金supported by the National Natural Science Foundation of China(Grant Nos.91748209 and 11402229)the specialized research projects of Huanjiang Laboratory.
文摘A novel wrist-inspired soft actuator,which is driven by a magneto-pneumatic hybrid system and based on a Kresling origami unit,is proposed.The geometric model,kinematic analysis model,and quasistatic analysis model of the Kresling origami unit are presented.A key focus is on the formulation and investigation of the variation in rotation angle using the kinematic analysis model.A wrist-inspired soft actuator is designed,and its quasistatic characteristics are validated through various experiments.The paper proposes an innovative magneto-pneumatic hybrid actuation method,capable of achieving bidirectional torsion.This actuation method is experimentally validated,demonstrating the actuator's ability to maintain 3 steady states and its capability for bidirectional torsion deformation.Furthermore,the paper highlights the potential of the Kresling origami unit in designing soft actuators capable of achieving large rotation angles.For instance,an actuator with 6 sides(n=6)is shown to achieve a rotation angle of 239.5°,and its rotation ratio exceeds 277°,about twice the largest one reported in other literature.The actuator offers a practical and effective solution for bidirectional torsion deformation in soft robotic applications.
