This study investigates the spatial and temporal variation of fractal dimension and b-value for the eastern part of the Himalaya and adjoining area(26°N–31°N and 87°E–98°E).The analysis is carrie...This study investigates the spatial and temporal variation of fractal dimension and b-value for the eastern part of the Himalaya and adjoining area(26°N–31°N and 87°E–98°E).The analysis is carried out on the earthquake dataset of 1373 events(Mc=4.0)by sliding window technique for the period 1964 to 2020.The region is divided into three sub regions A(87°E–92°E),B(92°E–94°E)and C(94°E–98°E).The b-value computed for the region A comprising eastern Nepal is smaller compared to other two regions which infers the possible high stress and asperities in the region.High spatial fractal dimension(Dc>1.5)and low temporal fractal dimension(Dt<0.31)are computed for the regions.High spatial fractal dimension may indicate that fractures generating earthquakes are approaching a 2D structure and low temporal fractal dimension implies high clustering of earthquake’s epicenters.The b value shows a weak negative correlation with Dc for regions A and C while a weak positive correlation is observed for the region B.Based on b-value and fractal dimension,this study explains the frequency of earthquakes and heterogeneity of the seismogenic structure in this part of the Himalaya.展开更多
Rational and accurate solar energy databases, essential for designing, sizing and performing the solar energy systems in any part of the world, are not easily accessible in different localities of Nepal. In this study...Rational and accurate solar energy databases, essential for designing, sizing and performing the solar energy systems in any part of the world, are not easily accessible in different localities of Nepal. In this study, daily global solar radiation, sunshine hours and meteorological data for Biratnagar, Kathmandu, Pokhara and Jumla have been used to derive the regression constants. The linear regression technique has been used to develop a model for Biratnagar, Kathmandu, Pokhara and Jumla. The model has calculated the global solar radiation for these locations. The values of global solar radiation estimated by the model are found to be in close agreement with measured values of respective sites. The estimated values were compared with Angstrom-Prescott model and examined using the root mean square error (RMSE), mean bias error (MBE), mean percentage error (MPE), coefficient of regression (R), coefficient of determinant (R2) and correlation coefficient (CC) statistical techniques. Thus, the resultant correlations and linear regression relations may be then used for the locations of similar meteorological/geographical characteristics and also can be used to estimate the missing data of solar radiation for the respective site.展开更多
Thermo-physical properties of Al-Mg alloys in molten state at 1073 K have been studied using thermodynamic modeling. Thermodynamic properties, such as free energy of mixing, heat of mixing, entropy of mixing, activiti...Thermo-physical properties of Al-Mg alloys in molten state at 1073 K have been studied using thermodynamic modeling. Thermodynamic properties, such as free energy of mixing, heat of mixing, entropy of mixing, activities and structural properties, such as concentration fluctuation in long wavelength limit, Warren-Cowely short range order parameter have been studied at 1073 K, 1173 K, 1273 K and 1373 K on the basis of regular associated solution model. The surface properties such as surface concentrations and surface tension of the liquid alloys have been studied by using Butler’s model. A consistent set of model parameters have also been obtained by using optimization procedure based on statistical thermodynamics. Our analysis reveals that Al-Mg alloy is moderately interacting and it shows ordering nature at 1073 K. The nature of the alloys changes from ordering to segregating as the temperature increases.展开更多
A kinetic simulation model has been employed to study the properties of an electronegative magnetized plasma sheath assuming the cut-off distribution of electrons and negative ions.The fundamental kinetic Bohm conditi...A kinetic simulation model has been employed to study the properties of an electronegative magnetized plasma sheath assuming the cut-off distribution of electrons and negative ions.The fundamental kinetic Bohm condition for the electronegative magnetized plasma has paramount importance for the formation of a stationary plasma sheath near the material wall.The presence of an oblique magnetic field in an electronegative plasma affects the ion distribution at the plasma injection side and at the wall.The temperature profile of negative charged particles has a non-uniform distribution,which determines the energy flow towards the wall.展开更多
A spatial orientation of angular momentum vectors of galaxies in six dynamically unstable Abell clusters（S1171, S0001, A1035, A1373, A1474 and A4053） is studied. For this, twodimensional observed parameters（e.g., p...A spatial orientation of angular momentum vectors of galaxies in six dynamically unstable Abell clusters（S1171, S0001, A1035, A1373, A1474 and A4053） is studied. For this, twodimensional observed parameters（e.g., positions, diameters and position angles） are converted into three-dimensional（3D） rotation axes of the galaxy using the ＇position angle-inclination＇ method. The expected isotropic distribution curves for angular momentum vectors are obtained by performing random simulations. The observed and expected distributions are compared using several statistical tests.No preferred alignments of angular momentum vectors of galaxies are noticed in all six dynamically unstable clusters, supporting the hierarchy model of galaxy formation. These clusters have a larger value of velocity dispersion. However, local effects are noticed in the clusters that have substructures in the1D-3D number density maps.展开更多
Kinetic theory has been employed to investigate the magnetized plasma-sheath structure and its characteristics in the presence of more than one species of negatively charged particles:hot electrons,cold electrons,and ...Kinetic theory has been employed to investigate the magnetized plasma-sheath structure and its characteristics in the presence of more than one species of negatively charged particles:hot electrons,cold electrons,and negative ions.The cold electrons and negative ions are considered to obey a Maxwellian distribution,whereas the hot electrons follow a truncated Maxwellian distribution.The Bohm sheath condition has been extended for the case of more than one species of negatively charged particles,in which the concentration of hot electrons has a crucial role in achieving the Bohm velocity.The thermal motion of hot electrons is much higher compared to cold electrons and negative ions,such that the variation of hot electron concentrations and the temperature ratio of hot to cold electrons play a key role in the determination of the plasma-sheath parameters:particle densities,electrostatic potential,the flow of positive ions towards the wall,and sheath thickness.We have estimated the deviation of the resultant drift velocity of positive ions on the plane perpendicular to the wall from the parallel component at the presheath–sheath interface.It is found that the deviation between the two velocity components increases with an increase in the obliqueness of the magnetic field.Furthermore,the results obtained from the kinetic trajectory simulation model are compared with the results obtained using a fluid model;the results are qualitatively similar,although the potential varies by less than 4%in terms of the magnitude at the wall.展开更多
Background: The thyroid status is evaluated by two clinical diagnostic tests which are thyroid ultrasonography and thyroid function tests. The objective of this research is to critically analyze the age and gender bas...Background: The thyroid status is evaluated by two clinical diagnostic tests which are thyroid ultrasonography and thyroid function tests. The objective of this research is to critically analyze the age and gender based variations of thyroid volume and thyroid hormone levels in the hospital based euthyroid subjects. Methodology: A total of 221 euthyroid subjects aged 1 - 86 years were selected to observe the normal thyroid size by ultrasonography at Department of Radiology and the thyroid function test values (FT3, FT4 and TSH) of 2413 euthyroid subjects aged (Results: The best fitted equations with significant correlation coefficients and p Conclusion: The thyroid size first increases and then decreases whereas the thyroxin level first decreases and then increases with aging. Left lobe volume is almost same for both genders and right lobe volume is higher in males. The thyroid size in menarche and menopause periods of females is larger than that of males. Such age- and gender-specific changes recommend the new refer-ence ranges for the normal thyroid functions.展开更多
In this work, we construct electrodes of brass to produce plasma by arc discharge and is characterized by using a movableLangmuir single probe. It is a simple way to measure plasma parameters such as electron temperat...In this work, we construct electrodes of brass to produce plasma by arc discharge and is characterized by using a movableLangmuir single probe. It is a simple way to measure plasma parameters such as electron temperature, electron density and iondensity. A movable Langmuir single probe technique has a reference point since it is biased with reference to any one electrode ofthe plasma producing system. The values obtained are at atmospheric pressure. The plasma thus produced in laboratory has variousapplications which include gaseous discharge, plasma torch, sputtering, laser produced plasma as well as tokamak plasma.展开更多
We present an analysis of the winding sense（S and Z-shapes） of 1 621 field galaxies that have radial velocity between 3 000 km s-1 and 5 000 km s-1.The preferred alignments of S-and Z-shaped galaxies are studied usi...We present an analysis of the winding sense（S and Z-shapes） of 1 621 field galaxies that have radial velocity between 3 000 km s-1 and 5 000 km s-1.The preferred alignments of S-and Z-shaped galaxies are studied using chi-square,autocorrelation and Fourier series tests.We classify all the galaxies into 32 subsamples and notice a good agreement between the position angle（PA） distribution of the S-and Zshaped galaxies.The homogeneous distribution of the S-and Z-shaped galaxies is more noticeable for the late-type spirals（Sc,Scd,Sd and Sm） than for the early-types（Sa,Sab,Sb and Sbc） .A significant dominance of S-mode galaxies is apparent in the barred spirals.A random alignment is evident in the PA-distribution of Z-and S-mode spirals.In addition,a homogeneous distribution of the S-and Z-shaped galaxies is found to be invariant under global expansion.The PA-distribution of the total S-mode galaxies is found to be random,whereas a preferred alignment is clear for all the Zmode galaxies.It is found that the galactic planes of Z-mode galaxies tend to lie in the equatorial plane.展开更多
In this paper, the present developments of copper vapor laser technology were computational modeling and simulations methods. In most of the cases, before the experiment, the functions of electrical parameters can be ...In this paper, the present developments of copper vapor laser technology were computational modeling and simulations methods. In most of the cases, before the experiment, the functions of electrical parameters can be predicted by the use of physical simulation codes. A single simulation model describing the discharge circuitry was introduced. By solving the equations of circuit via Runge-Kutta method, the current and voltage pulses of the discharge tube were investigated, which are in good agreement with the experimental results of the same laser.展开更多
In the present study,the spatial-temporal distribution of b-value along the five faults area(the Judi fault,Thaple fault,Kathmandu fault,Motihari-Gauri Shanker fault,and Motihari-Everest fault)was investigated after t...In the present study,the spatial-temporal distribution of b-value along the five faults area(the Judi fault,Thaple fault,Kathmandu fault,Motihari-Gauri Shanker fault,and Motihari-Everest fault)was investigated after the Gorkha earthquake(M7.8).The earthquake catalog of 10,500 events was prepared by compiling the published catalogs.The study area is bounded in the central Himalaya from 26.5°to 29°in latitude direction and 84°to 87°in longitude direction.The frequency magnitude distribution shows the variation of the b-value along with fault areas from 0.45 to 0.69,indicating a common characteristic of aftershock sequences.In particular,the Judi fault area,Thaple fault area,and Motihari-Everest fault area are characterized by the low b-values of 0.45±0.02,0.48±0.02,and 0.55±0.04,respectively.These regions could be the source region for future earthquakes.The low b-value observed for fault areas are also consistent with the thrust faulting pattern in the region as indicated by the focal mechanism of mainshock and major aftershocks.The temporal variation of b-value shows inevitable fluctuations during25 April to 12 May 2015.Among the area selected,the Motihari-Everest fault area is in critical strain(mechanically locked)conditions,as indicated by the stepwise energy release pattern.展开更多
On April 25, 2015, Nepal was struck by the MW7.8 Gorkha earthquake followed by an intense aftershock sequence. It was one of the most destructive earthquakes in the Himalayan arc, causing more than 8900 fatalities. In...On April 25, 2015, Nepal was struck by the MW7.8 Gorkha earthquake followed by an intense aftershock sequence. It was one of the most destructive earthquakes in the Himalayan arc, causing more than 8900 fatalities. In this study, we analyzed the dataset (429 events, magnitude of completeness (Mc) ≥ 4.2 local magnitude) of the first 45 days after the Gorkha earthquake to estimate the seismicity parameters b-value, D-value, and p-value. We used the maximum likelihood method to estimate the b-value and Omori-Utsu parameters, whereas the correlation integral method was applied to estimate the fractal dimension (D-value). The analysis was carried out using running and sliding window techniques. The lowest b-value (0.57 ± 0.04) and the highest D-value (1.65 ± 0.02) were computed at the time of the Gorkha earthquake, after which the b-value significantly increased to a maximum of 1.57. It again dropped to 0.93 at the time of the major aftershock on May 12, 2015. The D-value showed an initial quick drop and then decreased in a wavy pattern until the end of the study period, indicating the clustering and scattering of earthquakes in a fault region. The b-value contour map identified the eastern part of the study area as a high stress region (b = ~0.8), implying that the stress shifted to that region. The D-value contour map reveals that the seismogenic structure shifted from linear to planar in the region. The rate of aftershock decay (p = 0.86 ± 0.04) for a short period reflects that the level of stress decreased rapidly. This study helps to understand the level of stress and seismicity pattern of a region, which could be useful for aftershock studies.展开更多
<strong>Purpose:</strong> <span style="font-family:""><span style="font-family:Verdana;">The study is aimed to establish the dosimetric characteristics of field-in-fiel...<strong>Purpose:</strong> <span style="font-family:""><span style="font-family:Verdana;">The study is aimed to establish the dosimetric characteristics of field-in-field (FiF) technique for carcinoma of breast treatment in Nepal. We assumed that FIF technique may result in improved dose distribution and reduced acute toxicity in these patients. </span><b><span style="font-family:Verdana;">Methods: </span></b><span style="font-family:Verdana;">Forty breast cancer patient</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> participated in this study. A total dose of 50 Gy in 25 fractions was prescribed to the planning target volume. FiF plan was generated in treatment planning system. Dose volume histograms w</span><span style="font-family:Verdana;">ere</span><span style="font-family:""><span style="font-family:Verdana;"> evaluated for PTV and organs at risks. Several parameters were analyzed for the PTVs and organ at risks (OARs) together with the Conformity index (CI), and the Homogeneity index (HI). </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">The dose coverage of breast volume was achieved. The V</span><sub><span style="font-family:Verdana;">95%</span></sub><span style="font-family:Verdana;"> (volume of 95%) of PTV covered D</span><sub><span style="font-family:Verdana;">95%</span></sub><span style="font-family:Verdana;"> (Dose of 95%). The PTV dose was covered to 49.98 ± 0.9 Gy and 49.81 ± 1.1 Gy for the left and right breast, respectively. The mean lung dose was 14.87 ± 0.91 Gy. The homogeneity index (0.26 ± 0.17 and 0.22 ± 0.13) and conformity index (1.59 ± 0.75 and 1.36 ± 0.45) were analyzed for left and right breast, respectively. </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">The study supports the viability of FiF technique in the treatment of breast cancer in Nepal. The FIF technique enables better dose distribution in the PTV and reduces dose to OARs. The FiF technique provides dosimetric advantages and requires less planning time.</span></span>展开更多
Using the Thomas-Fermi quark model,a collective,spherically symmetric density of states is created to represent a gas of interacting fermions with various degeneracies at zero temperature.Over a family of pentaquarks,...Using the Thomas-Fermi quark model,a collective,spherically symmetric density of states is created to represent a gas of interacting fermions with various degeneracies at zero temperature.Over a family of pentaquarks,uudcc,color interaction probabilities were obtained after averaging over all the possible configurations.Three different functions are developed for light,charm,and anti-charm quarks and are assumed to be linearly related by some proportionality constants.Interesting patterns of quark distributions are observed while analyzing the quark function consistency conditions for such constants.展开更多
基金University Grants Commission(UGC),Nepal for providing financial support。
文摘This study investigates the spatial and temporal variation of fractal dimension and b-value for the eastern part of the Himalaya and adjoining area(26°N–31°N and 87°E–98°E).The analysis is carried out on the earthquake dataset of 1373 events(Mc=4.0)by sliding window technique for the period 1964 to 2020.The region is divided into three sub regions A(87°E–92°E),B(92°E–94°E)and C(94°E–98°E).The b-value computed for the region A comprising eastern Nepal is smaller compared to other two regions which infers the possible high stress and asperities in the region.High spatial fractal dimension(Dc>1.5)and low temporal fractal dimension(Dt<0.31)are computed for the regions.High spatial fractal dimension may indicate that fractures generating earthquakes are approaching a 2D structure and low temporal fractal dimension implies high clustering of earthquake’s epicenters.The b value shows a weak negative correlation with Dc for regions A and C while a weak positive correlation is observed for the region B.Based on b-value and fractal dimension,this study explains the frequency of earthquakes and heterogeneity of the seismogenic structure in this part of the Himalaya.
文摘Rational and accurate solar energy databases, essential for designing, sizing and performing the solar energy systems in any part of the world, are not easily accessible in different localities of Nepal. In this study, daily global solar radiation, sunshine hours and meteorological data for Biratnagar, Kathmandu, Pokhara and Jumla have been used to derive the regression constants. The linear regression technique has been used to develop a model for Biratnagar, Kathmandu, Pokhara and Jumla. The model has calculated the global solar radiation for these locations. The values of global solar radiation estimated by the model are found to be in close agreement with measured values of respective sites. The estimated values were compared with Angstrom-Prescott model and examined using the root mean square error (RMSE), mean bias error (MBE), mean percentage error (MPE), coefficient of regression (R), coefficient of determinant (R2) and correlation coefficient (CC) statistical techniques. Thus, the resultant correlations and linear regression relations may be then used for the locations of similar meteorological/geographical characteristics and also can be used to estimate the missing data of solar radiation for the respective site.
文摘Thermo-physical properties of Al-Mg alloys in molten state at 1073 K have been studied using thermodynamic modeling. Thermodynamic properties, such as free energy of mixing, heat of mixing, entropy of mixing, activities and structural properties, such as concentration fluctuation in long wavelength limit, Warren-Cowely short range order parameter have been studied at 1073 K, 1173 K, 1273 K and 1373 K on the basis of regular associated solution model. The surface properties such as surface concentrations and surface tension of the liquid alloys have been studied by using Butler’s model. A consistent set of model parameters have also been obtained by using optimization procedure based on statistical thermodynamics. Our analysis reveals that Al-Mg alloy is moderately interacting and it shows ordering nature at 1073 K. The nature of the alloys changes from ordering to segregating as the temperature increases.
基金Suresh Basnet would like to acknowledge the University Grants Commission,Nepal for the PhD fellowship.
文摘A kinetic simulation model has been employed to study the properties of an electronegative magnetized plasma sheath assuming the cut-off distribution of electrons and negative ions.The fundamental kinetic Bohm condition for the electronegative magnetized plasma has paramount importance for the formation of a stationary plasma sheath near the material wall.The presence of an oblique magnetic field in an electronegative plasma affects the ion distribution at the plasma injection side and at the wall.The temperature profile of negative charged particles has a non-uniform distribution,which determines the energy flow towards the wall.
文摘A spatial orientation of angular momentum vectors of galaxies in six dynamically unstable Abell clusters（S1171, S0001, A1035, A1373, A1474 and A4053） is studied. For this, twodimensional observed parameters（e.g., positions, diameters and position angles） are converted into three-dimensional（3D） rotation axes of the galaxy using the ＇position angle-inclination＇ method. The expected isotropic distribution curves for angular momentum vectors are obtained by performing random simulations. The observed and expected distributions are compared using several statistical tests.No preferred alignments of angular momentum vectors of galaxies are noticed in all six dynamically unstable clusters, supporting the hierarchy model of galaxy formation. These clusters have a larger value of velocity dispersion. However, local effects are noticed in the clusters that have substructures in the1D-3D number density maps.
基金the University Grants Commission,Nepal for the PhD fellowship Ph D/075-76S&T-16。
文摘Kinetic theory has been employed to investigate the magnetized plasma-sheath structure and its characteristics in the presence of more than one species of negatively charged particles:hot electrons,cold electrons,and negative ions.The cold electrons and negative ions are considered to obey a Maxwellian distribution,whereas the hot electrons follow a truncated Maxwellian distribution.The Bohm sheath condition has been extended for the case of more than one species of negatively charged particles,in which the concentration of hot electrons has a crucial role in achieving the Bohm velocity.The thermal motion of hot electrons is much higher compared to cold electrons and negative ions,such that the variation of hot electron concentrations and the temperature ratio of hot to cold electrons play a key role in the determination of the plasma-sheath parameters:particle densities,electrostatic potential,the flow of positive ions towards the wall,and sheath thickness.We have estimated the deviation of the resultant drift velocity of positive ions on the plane perpendicular to the wall from the parallel component at the presheath–sheath interface.It is found that the deviation between the two velocity components increases with an increase in the obliqueness of the magnetic field.Furthermore,the results obtained from the kinetic trajectory simulation model are compared with the results obtained using a fluid model;the results are qualitatively similar,although the potential varies by less than 4%in terms of the magnitude at the wall.
文摘Background: The thyroid status is evaluated by two clinical diagnostic tests which are thyroid ultrasonography and thyroid function tests. The objective of this research is to critically analyze the age and gender based variations of thyroid volume and thyroid hormone levels in the hospital based euthyroid subjects. Methodology: A total of 221 euthyroid subjects aged 1 - 86 years were selected to observe the normal thyroid size by ultrasonography at Department of Radiology and the thyroid function test values (FT3, FT4 and TSH) of 2413 euthyroid subjects aged (Results: The best fitted equations with significant correlation coefficients and p Conclusion: The thyroid size first increases and then decreases whereas the thyroxin level first decreases and then increases with aging. Left lobe volume is almost same for both genders and right lobe volume is higher in males. The thyroid size in menarche and menopause periods of females is larger than that of males. Such age- and gender-specific changes recommend the new refer-ence ranges for the normal thyroid functions.
文摘In this work, we construct electrodes of brass to produce plasma by arc discharge and is characterized by using a movableLangmuir single probe. It is a simple way to measure plasma parameters such as electron temperature, electron density and iondensity. A movable Langmuir single probe technique has a reference point since it is biased with reference to any one electrode ofthe plasma producing system. The values obtained are at atmospheric pressure. The plasma thus produced in laboratory has variousapplications which include gaseous discharge, plasma torch, sputtering, laser produced plasma as well as tokamak plasma.
文摘We present an analysis of the winding sense（S and Z-shapes） of 1 621 field galaxies that have radial velocity between 3 000 km s-1 and 5 000 km s-1.The preferred alignments of S-and Z-shaped galaxies are studied using chi-square,autocorrelation and Fourier series tests.We classify all the galaxies into 32 subsamples and notice a good agreement between the position angle（PA） distribution of the S-and Zshaped galaxies.The homogeneous distribution of the S-and Z-shaped galaxies is more noticeable for the late-type spirals（Sc,Scd,Sd and Sm） than for the early-types（Sa,Sab,Sb and Sbc） .A significant dominance of S-mode galaxies is apparent in the barred spirals.A random alignment is evident in the PA-distribution of Z-and S-mode spirals.In addition,a homogeneous distribution of the S-and Z-shaped galaxies is found to be invariant under global expansion.The PA-distribution of the total S-mode galaxies is found to be random,whereas a preferred alignment is clear for all the Zmode galaxies.It is found that the galactic planes of Z-mode galaxies tend to lie in the equatorial plane.
文摘In this paper, the present developments of copper vapor laser technology were computational modeling and simulations methods. In most of the cases, before the experiment, the functions of electrical parameters can be predicted by the use of physical simulation codes. A single simulation model describing the discharge circuitry was introduced. By solving the equations of circuit via Runge-Kutta method, the current and voltage pulses of the discharge tube were investigated, which are in good agreement with the experimental results of the same laser.
基金Tribhuvan University,Nepal for providing sabbatical leave and University Grants Commission(UGC),Nepal for providing financial support in the form of fellowship
文摘In the present study,the spatial-temporal distribution of b-value along the five faults area(the Judi fault,Thaple fault,Kathmandu fault,Motihari-Gauri Shanker fault,and Motihari-Everest fault)was investigated after the Gorkha earthquake(M7.8).The earthquake catalog of 10,500 events was prepared by compiling the published catalogs.The study area is bounded in the central Himalaya from 26.5°to 29°in latitude direction and 84°to 87°in longitude direction.The frequency magnitude distribution shows the variation of the b-value along with fault areas from 0.45 to 0.69,indicating a common characteristic of aftershock sequences.In particular,the Judi fault area,Thaple fault area,and Motihari-Everest fault area are characterized by the low b-values of 0.45±0.02,0.48±0.02,and 0.55±0.04,respectively.These regions could be the source region for future earthquakes.The low b-value observed for fault areas are also consistent with the thrust faulting pattern in the region as indicated by the focal mechanism of mainshock and major aftershocks.The temporal variation of b-value shows inevitable fluctuations during25 April to 12 May 2015.Among the area selected,the Motihari-Everest fault area is in critical strain(mechanically locked)conditions,as indicated by the stepwise energy release pattern.
文摘On April 25, 2015, Nepal was struck by the MW7.8 Gorkha earthquake followed by an intense aftershock sequence. It was one of the most destructive earthquakes in the Himalayan arc, causing more than 8900 fatalities. In this study, we analyzed the dataset (429 events, magnitude of completeness (Mc) ≥ 4.2 local magnitude) of the first 45 days after the Gorkha earthquake to estimate the seismicity parameters b-value, D-value, and p-value. We used the maximum likelihood method to estimate the b-value and Omori-Utsu parameters, whereas the correlation integral method was applied to estimate the fractal dimension (D-value). The analysis was carried out using running and sliding window techniques. The lowest b-value (0.57 ± 0.04) and the highest D-value (1.65 ± 0.02) were computed at the time of the Gorkha earthquake, after which the b-value significantly increased to a maximum of 1.57. It again dropped to 0.93 at the time of the major aftershock on May 12, 2015. The D-value showed an initial quick drop and then decreased in a wavy pattern until the end of the study period, indicating the clustering and scattering of earthquakes in a fault region. The b-value contour map identified the eastern part of the study area as a high stress region (b = ~0.8), implying that the stress shifted to that region. The D-value contour map reveals that the seismogenic structure shifted from linear to planar in the region. The rate of aftershock decay (p = 0.86 ± 0.04) for a short period reflects that the level of stress decreased rapidly. This study helps to understand the level of stress and seismicity pattern of a region, which could be useful for aftershock studies.
文摘<strong>Purpose:</strong> <span style="font-family:""><span style="font-family:Verdana;">The study is aimed to establish the dosimetric characteristics of field-in-field (FiF) technique for carcinoma of breast treatment in Nepal. We assumed that FIF technique may result in improved dose distribution and reduced acute toxicity in these patients. </span><b><span style="font-family:Verdana;">Methods: </span></b><span style="font-family:Verdana;">Forty breast cancer patient</span></span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> participated in this study. A total dose of 50 Gy in 25 fractions was prescribed to the planning target volume. FiF plan was generated in treatment planning system. Dose volume histograms w</span><span style="font-family:Verdana;">ere</span><span style="font-family:""><span style="font-family:Verdana;"> evaluated for PTV and organs at risks. Several parameters were analyzed for the PTVs and organ at risks (OARs) together with the Conformity index (CI), and the Homogeneity index (HI). </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">The dose coverage of breast volume was achieved. The V</span><sub><span style="font-family:Verdana;">95%</span></sub><span style="font-family:Verdana;"> (volume of 95%) of PTV covered D</span><sub><span style="font-family:Verdana;">95%</span></sub><span style="font-family:Verdana;"> (Dose of 95%). The PTV dose was covered to 49.98 ± 0.9 Gy and 49.81 ± 1.1 Gy for the left and right breast, respectively. The mean lung dose was 14.87 ± 0.91 Gy. The homogeneity index (0.26 ± 0.17 and 0.22 ± 0.13) and conformity index (1.59 ± 0.75 and 1.36 ± 0.45) were analyzed for left and right breast, respectively. </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">The study supports the viability of FiF technique in the treatment of breast cancer in Nepal. The FIF technique enables better dose distribution in the PTV and reduces dose to OARs. The FiF technique provides dosimetric advantages and requires less planning time.</span></span>
文摘Using the Thomas-Fermi quark model,a collective,spherically symmetric density of states is created to represent a gas of interacting fermions with various degeneracies at zero temperature.Over a family of pentaquarks,uudcc,color interaction probabilities were obtained after averaging over all the possible configurations.Three different functions are developed for light,charm,and anti-charm quarks and are assumed to be linearly related by some proportionality constants.Interesting patterns of quark distributions are observed while analyzing the quark function consistency conditions for such constants.
