Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant...Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model.展开更多
To reveal the nature of locusts’visual reaction when stimulated by light,and to clarify the regulation characteristics of locusts’phototactic visual physiology and obtain good spectral light features for locusts’ph...To reveal the nature of locusts’visual reaction when stimulated by light,and to clarify the regulation characteristics of locusts’phototactic visual physiology and obtain good spectral light features for locusts’phototactic action,this study investigated locusts’visual spectrum response by characterizing their photoreceptive reaction to LED light using an AvaSpec fiber-optic spectrometer system.Locusts’phototactic response to spectral light was compared using this system.The results showed that locusts’visual reaction characterization presents a photo-induced vision spectrum effect and that by offsetting the main wavelength of light and the spectral peak intensity,a time-varying bio-regulation effect emerges.In addition,locusts’visual regulation ability to UV light is higher than that to violet light,whereas their reaction intensity is lower than to violet light,and the visual bio-regulatory force of locusts’visual system absorbing orange light to react sensitively becomes gradually higher than when absorbing green light as time goes on.Moreover,corresponding to nominal illumination with the same radiant energy and a visual spectrum response stimulated by UV,violet,orange,and green light,it appears that the visual spectrum window is symmetrical around 382 nm,400 nm,602 nm,and 530 nm,respectively,with no significant difference between spectral amplitudes and having a time-varying incremental characteristic with amplitude peak width.This indicates that the stimulus intensity of UV,violet,orange,and green light exceeds locusts’visual tolerance,causing them to generate regulation inactivation as a visual physiological reaction,whereas the visual window response effect stimulated by UV light presents an illumination timeliness effect.Simultaneously,time-varying characteristics of locusts’bio-behavior intensity show that light intensity can make up for locusts’visual sensitivity differences at various spectral wavelengths.Presented with differential response time,photosensitive behavior intensity,and induction effect induced by orange light,time is superior for orange light,the stimulation effect caused by violet light is the strongest,and the phototactic synergy effect caused by UV light is the best.展开更多
The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in c...The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.展开更多
The effects of the protic and aprotic polar solvents on the emission spectrum of the naphthalene-triethyl-amine system in THF were studied under conditions of steady-state illumination. The fluorescence spectrum of th...The effects of the protic and aprotic polar solvents on the emission spectrum of the naphthalene-triethyl-amine system in THF were studied under conditions of steady-state illumination. The fluorescence spectrum of the naphthalene-triethylamine system consists of two emission bands, the fluorescence band of naphthalene(band A, 329 nm) and the emission band of the exciplex(band B, 468 nm). The intensities of both the emission bands decrease with increasing the solvent polarity. The intensity of band B also decreases due to the hydrogen-bonding interaction between triethylamine and protic solvent, while that of band A increases. It is thus suggested that the quenching of naphthalene fluorescence by triethylamine in THF occurs through the charge transfer and electron transfer reactions. The spectral changes upon the increase of solvent polarity can be explained by the dependences of the equilibrium constant between exciplex and ion-pair and the rate constant for the electron transfer reaction from triethylamine to the excited naphthalene on the relative permittivity of solvent. It is shown that the formation of intermolecular hydrogen-bonding between triethylamine and protic solvent suppresses the quenching reaction by the decrease in free amine. Acetonitrile has only a polar effect and trichloroacetic acid only a hydrogen-bonding(or protonation) effect, while alcohols have both the effects. The effects of alcohols could be separated into the effects of solvent polarity and intermolecular hydrogen-bonding interaction quantitatively.展开更多
The colour of the Hall effect thruster＇s plume is often light-green, and sometimes a fuchsia plume appears during experiments. Based on a spectrum and colour analysis, and a comparison with normal plumes, a conclusio...The colour of the Hall effect thruster＇s plume is often light-green, and sometimes a fuchsia plume appears during experiments. Based on a spectrum and colour analysis, and a comparison with normal plumes, a conclusion is made that the density of the Xe ions and the temperature of electrons are low when the plume appears fuchsia. In this condition, most of the components of the plume are Xe atoms, and the ionization rate of the propellant is low.展开更多
All-atom molecular simulations and two-dimensional nuclear overhauser effect spectrum have been used to study the conformations of carnosine in aqueous solution. Intramolecular distances, root-mean-square deviation, r...All-atom molecular simulations and two-dimensional nuclear overhauser effect spectrum have been used to study the conformations of carnosine in aqueous solution. Intramolecular distances, root-mean-square deviation, radius of gyration, and solvent-accessible surface are used to characterize the properties of the carnosine. Carnosine can shift between extended and folded states, but exists mostly in extended state in water. Its preference for extension in pure water has been proven by the 2D nuclear magnetic resonance （NMR） experiment. The NMR experimental results are consistent with the molecular dynamics simulations.展开更多
In this work, natural neutron spectra at nine sites in Tibet region were measured using a multi-sphere neutron spectrometer. The altitude-dependence of the spectra total fluence rate and ambient dose equivalent rate w...In this work, natural neutron spectra at nine sites in Tibet region were measured using a multi-sphere neutron spectrometer. The altitude-dependence of the spectra total fluence rate and ambient dose equivalent rate were analyzed. From the normalized natural neutron spectra at different altitudes, the spectrum fractions for neutrons of greater than 0.1 MeV do not differ obviously, while those of the thermal neutrons differ greatly from each other. The total fluence rate, effective dose rate and the ambient dose equivalent rate varied with the altitude according to an exponential law.展开更多
Based on the passive spectroscopy,the D_α atomic emission spectra in the boundary region of the plasma have been measured by a high resolution optical spectroscopic multichannel analysis（OSMA） system in EAST tokama...Based on the passive spectroscopy,the D_α atomic emission spectra in the boundary region of the plasma have been measured by a high resolution optical spectroscopic multichannel analysis（OSMA） system in EAST tokamak.The Zeeman splitting of the D_α spectral lines has been observed.A fitting procedure by using a nonlinear least squares method was applied to fit and analyze all polarization π and ±σ components of the D_α atomic spectra to acquire the information of the local plasma.The spectral line shape was investigated according to emission spectra from different regions（e.g.,low-field side and high-field side） along the viewing chords.Each polarization component was fitted and classified into three energy categories（the cold,warm,and hot components） based on different atomic production processes,in consistent with the transition energy distribution by calculating the gradient of the D_α spectral profile.The emission position,magnetic field intensity,and flow velocity of a deuterium atom were also discussed in the context.展开更多
The rare earth complexes Tb（o-BrBA）3,Tb（m-BrBA）3 and Tb（p-BrBA）3 were synthesized using o-,m-,p-bromo benzoic acids（2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid） as ligand,respectively.Th...The rare earth complexes Tb（o-BrBA）3,Tb（m-BrBA）3 and Tb（p-BrBA）3 were synthesized using o-,m-,p-bromo benzoic acids（2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid） as ligand,respectively.The UV spectra showed that the absorption ability of Tb（m-BrBA）3 was the strongest.However,the fluorescent intensity of Tb（o-BrBA）3 was the weakest.The effect of the molecular structure,the energy level of Tb3＋ and energy transfer efficiency from ligands to Tb3＋ were discussed to explain the experimental results.The results indicated that,due to the large atomic radius of bromine,the steric effect caused by the different substitution bromine on the benzene ring might strongly affect the bond length formed by the coordination atoms and Tb3＋.The longer the bond length was,the lower the efficiency of energy transfer was,and the weaker the fluorescent intensity was.展开更多
Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and freque...Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation error.Moreover,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed.展开更多
Due to the randomness of earthquake wave magnitude and direction, and the uncertain direction of strong axis and weak axis in the construction of engineering structures, the effect of the direction of ground motion on...Due to the randomness of earthquake wave magnitude and direction, and the uncertain direction of strong axis and weak axis in the construction of engineering structures, the effect of the direction of ground motion on a structure are studied herein. Ground motion records usually contain three vertical ground motion data, which are obtained by sensors arranged in accordance with the EW （East -West） direction, NS （South- North） direction and perpendicular to the surface （z） direction, referring to the construction standard of seismic stations. The seismic records in the EW and NS directions are converted to Cartesian coordinates in accordance with the rotation of θ = 0°-180°, and consequently, a countless group of new ground motion time histories are obtained. Then, the characteristics of the ground motion time history and response spectrum of each group were studied, resulting in the following observations： （1） the peak and phase of ground motion are changed with the rotation of direction θ, so that the direction θ of the maximum peak ground motion can be determined; （2） response spectrum values of each group of ground motions change along with the direction θ, and their peak, predominant period and declining curve are also different as the changes occur; then, the angle θ in the direction of the maximum peak value or the widest predominant period can be determined; and （3） the seismic response of structures with different directions of ground motion inputs has been analyzed under the same earthquake record, and the results show the difference. For some ground motion records, such as the Taft seismic wave, these differences are significant. Next, the Lushan middle school gymnasium structure was analyzed and the calculation was checked using the proposed method, where the internal force of the upper space truss varied from 25% to 28%. The research results presented herein can be used for reference in choosing the ground motion when checking the actual damage to structures following earthquakes and explaining the seismic damage. Meanwhile, it also provides a reference value for research into the most severe ground motion.展开更多
The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples.Based on the conventional least-squares principle, this spectr...The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples.Based on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the Gi factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of lg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.展开更多
The article compares the IR absorption spectra of the gases of the Earth’s atmosphere with frequencies, close to the frequency of the maximum of thermal radiation of human. It is shown that such a gas is ozone. Being...The article compares the IR absorption spectra of the gases of the Earth’s atmosphere with frequencies, close to the frequency of the maximum of thermal radiation of human. It is shown that such a gas is ozone. Being in the transparency window of the atmosphere, it emits absorbed thermal radiation from the Earth. This radiation, in turn, gets to maximum heat absorption (radiation) of a human, and being with it in resonance, fuels him with energy. In larger cities this nourishment is weakened because of the smog due to the strong scattering of Earth radiation and ozone. Thus, the “greenhouse ozone” as a natural source of infrared radiation has beneficial effect on human.展开更多
This case presents a rarely seen combination of two Cocaine-induced syndromes occurring simultaneously. Levamisole-adultered cocaine leads to Levamisole-induced Vasculitis (LIV), while cocaine’s vasoconstrictive effe...This case presents a rarely seen combination of two Cocaine-induced syndromes occurring simultaneously. Levamisole-adultered cocaine leads to Levamisole-induced Vasculitis (LIV), while cocaine’s vasoconstrictive effect causes destruction of the osteo-cartilaginous structures of nose called Cocaine-induced midline destructive lesions (CIMDL). This case raises awareness of a new pattern of recognition in order to avoid misdiagnosis. We present a case of a 51-year-old male cocaine user who developed severe left-sided ear pain and yellowish secretions with circular necrotic lesions in the nose, right earlobe, and dorsum of feet bilaterally. An extensive workup to assess purpuric lesions’ etiology, including vasculitis, collagen vasculitides, anti-phospholipid syndrome, hypercoagulable state and infectious process, was performed and found negative. He developed bilateral tympanic membrane perforation and purpuric necrotic skin lesions, at the same time, due to CIMDL and LIV, respectively. These two syndromes rarely present simultaneously in a patient. This case report exhibits a new Cocaine-induced clinical presentation that will help hospitalists recognize the disease and avoid misdiagnosis leading to unnecessary tests, prolonged hospitalization, and higher healthcare costs. Diagnosis is challenging, as it consists of establishing a temporal relationship between cocaine ingestion and symptoms’ onset. This disease usually has a benign progression because symptoms frequently resolve without intervention.展开更多
Many studies have indicated that structural strain will be significantly influenced by temperature variations,and a good understanding of the effect of temperature on structural strain is essential.A structural health...Many studies have indicated that structural strain will be significantly influenced by temperature variations,and a good understanding of the effect of temperature on structural strain is essential.A structural health monitoring system has been installed in a typical Tibetan timber building to measure the structural strains and ambient temperature since 2012.This paper presents the correlation between temperature and strain data from the monitored structure.A method combining singular spectrum analysis and polynomial regression is proposed for modeling the temperature induced strains in the structure.Singular spectrum analysis is applied to smooth the temperature data,and the correlation between the resulting temperature time series and the measured strains is obtained by polynomial regression.Parameters of the singular spectrum analysis and the regression model are selected to have the least regression error.Results show that the proposed method has both good reproduction and prediction capabilities for temperature induced strains,and that the method is accurate and effective for eliminating the effect of temperature from the measured strain.A standardized Novelty Index based on the residual strain is also used for the condition assessment of the structure.展开更多
The explicit finite element analysis method combined with the artificial transmitting boundary theory is performed to evaluate the adjacent terrain effects on ground motion,and the influence of the distance between ad...The explicit finite element analysis method combined with the artificial transmitting boundary theory is performed to evaluate the adjacent terrain effects on ground motion,and the influence of the distance between adjacent terrains on the topographical amplification effects on ground motion is studied. The results show that:( 1) Compared to the case of a single hill,the presence of adjacent hills has little effect on the shape of the spectral ratio curve,but has a significant effect on the value of spectral ratio,which is dependent on the locations of observation points.( 2) The presence of adjacent hills has a greater effect on high-frequency ground motion,and with the increase of the distance between adjacent hills,such an effect weakens gradually,and the effect of the composite topography combined with multiple hills on ground motion gradually approaches that of a single hill.展开更多
Combined with irregular wave-maker, the growing process of Wave Energy Spectrum in shallow water can be studied in wind wave channel on different water depth conditions, and its transformation characteristics and rule...Combined with irregular wave-maker, the growing process of Wave Energy Spectrum in shallow water can be studied in wind wave channel on different water depth conditions, and its transformation characteristics and rules can be obtained.展开更多
文摘Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model.
基金The authors acknowledge that this work was financially supported by the Scientific and technological project in Henan Province(Grant No.212102110139)the China Agricultural Research System(Grant No.CARS-03)the Henan Engineering Research Center of Biological Pesticide&Fertilizer Development and Synergistic Application.
文摘To reveal the nature of locusts’visual reaction when stimulated by light,and to clarify the regulation characteristics of locusts’phototactic visual physiology and obtain good spectral light features for locusts’phototactic action,this study investigated locusts’visual spectrum response by characterizing their photoreceptive reaction to LED light using an AvaSpec fiber-optic spectrometer system.Locusts’phototactic response to spectral light was compared using this system.The results showed that locusts’visual reaction characterization presents a photo-induced vision spectrum effect and that by offsetting the main wavelength of light and the spectral peak intensity,a time-varying bio-regulation effect emerges.In addition,locusts’visual regulation ability to UV light is higher than that to violet light,whereas their reaction intensity is lower than to violet light,and the visual bio-regulatory force of locusts’visual system absorbing orange light to react sensitively becomes gradually higher than when absorbing green light as time goes on.Moreover,corresponding to nominal illumination with the same radiant energy and a visual spectrum response stimulated by UV,violet,orange,and green light,it appears that the visual spectrum window is symmetrical around 382 nm,400 nm,602 nm,and 530 nm,respectively,with no significant difference between spectral amplitudes and having a time-varying incremental characteristic with amplitude peak width.This indicates that the stimulus intensity of UV,violet,orange,and green light exceeds locusts’visual tolerance,causing them to generate regulation inactivation as a visual physiological reaction,whereas the visual window response effect stimulated by UV light presents an illumination timeliness effect.Simultaneously,time-varying characteristics of locusts’bio-behavior intensity show that light intensity can make up for locusts’visual sensitivity differences at various spectral wavelengths.Presented with differential response time,photosensitive behavior intensity,and induction effect induced by orange light,time is superior for orange light,the stimulation effect caused by violet light is the strongest,and the phototactic synergy effect caused by UV light is the best.
基金supported by the National Natural Science Funds of China(Grant No.81703664)Science and Technology Funds of Lanzhou,China(Grant No.201603111)
文摘The traditional Chinese medicine of Radix Hedysari plays an important role in invigorating gas for ascending, benefiting blood for promoting production of fluid, and promoting circulation for removing obstruction in collaterals, which is consistent with the principle of treatment for osteoporosis. This study is designed to investigate the bioactive components on increasing peak bone mass (PBM) by exploring the spectrum-effect relationship between chromatography fingerprints and effect. Multiple indicators are selected to evaluate the pharmacological activity. In fingerprints, 21 common peaks are obtained, five of which are identified. Furthermore, gray relational analysis (GRA) is a quantitative method of gray system theory and is used to describe the correlation degree of common peaks and pharmacological activities with relational value. 21 components are then divided into three different regions, of which ononin and calycosin play an extremely significant role in increasing PBM. In addition, factor analysis and hierarchical cluster analysis (HCA) are used to screen the optimal producing area for Radix Hedysari. This provides a comprehensive and efficient method to improve the quality evaluation of Radix Hedysari, confirming the bioactive components for PBM-enhancement and further develop its medicinal value.
文摘The effects of the protic and aprotic polar solvents on the emission spectrum of the naphthalene-triethyl-amine system in THF were studied under conditions of steady-state illumination. The fluorescence spectrum of the naphthalene-triethylamine system consists of two emission bands, the fluorescence band of naphthalene(band A, 329 nm) and the emission band of the exciplex(band B, 468 nm). The intensities of both the emission bands decrease with increasing the solvent polarity. The intensity of band B also decreases due to the hydrogen-bonding interaction between triethylamine and protic solvent, while that of band A increases. It is thus suggested that the quenching of naphthalene fluorescence by triethylamine in THF occurs through the charge transfer and electron transfer reactions. The spectral changes upon the increase of solvent polarity can be explained by the dependences of the equilibrium constant between exciplex and ion-pair and the rate constant for the electron transfer reaction from triethylamine to the excited naphthalene on the relative permittivity of solvent. It is shown that the formation of intermolecular hydrogen-bonding between triethylamine and protic solvent suppresses the quenching reaction by the decrease in free amine. Acetonitrile has only a polar effect and trichloroacetic acid only a hydrogen-bonding(or protonation) effect, while alcohols have both the effects. The effects of alcohols could be separated into the effects of solvent polarity and intermolecular hydrogen-bonding interaction quantitatively.
基金supported by the National Defence Foundation Research(No.K1403060719)
文摘The colour of the Hall effect thruster＇s plume is often light-green, and sometimes a fuchsia plume appears during experiments. Based on a spectrum and colour analysis, and a comparison with normal plumes, a conclusion is made that the density of the Xe ions and the temperature of electrons are low when the plume appears fuchsia. In this condition, most of the components of the plume are Xe atoms, and the ionization rate of the propellant is low.
文摘All-atom molecular simulations and two-dimensional nuclear overhauser effect spectrum have been used to study the conformations of carnosine in aqueous solution. Intramolecular distances, root-mean-square deviation, radius of gyration, and solvent-accessible surface are used to characterize the properties of the carnosine. Carnosine can shift between extended and folded states, but exists mostly in extended state in water. Its preference for extension in pure water has been proven by the 2D nuclear magnetic resonance （NMR） experiment. The NMR experimental results are consistent with the molecular dynamics simulations.
基金Supported by the National Natural Science Foundation of China(No.11575294)
文摘In this work, natural neutron spectra at nine sites in Tibet region were measured using a multi-sphere neutron spectrometer. The altitude-dependence of the spectra total fluence rate and ambient dose equivalent rate were analyzed. From the normalized natural neutron spectra at different altitudes, the spectrum fractions for neutrons of greater than 0.1 MeV do not differ obviously, while those of the thermal neutrons differ greatly from each other. The total fluence rate, effective dose rate and the ambient dose equivalent rate varied with the altitude according to an exponential law.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11275231 and 11575249)the National Magnetic Confinement Fusion Energy Research Program of China(Grant No.2015GB110005)
文摘Based on the passive spectroscopy,the D_α atomic emission spectra in the boundary region of the plasma have been measured by a high resolution optical spectroscopic multichannel analysis（OSMA） system in EAST tokamak.The Zeeman splitting of the D_α spectral lines has been observed.A fitting procedure by using a nonlinear least squares method was applied to fit and analyze all polarization π and ±σ components of the D_α atomic spectra to acquire the information of the local plasma.The spectral line shape was investigated according to emission spectra from different regions（e.g.,low-field side and high-field side） along the viewing chords.Each polarization component was fitted and classified into three energy categories（the cold,warm,and hot components） based on different atomic production processes,in consistent with the transition energy distribution by calculating the gradient of the D_α spectral profile.The emission position,magnetic field intensity,and flow velocity of a deuterium atom were also discussed in the context.
基金Project supported by the National Natural Science Foundation of China (50973003)Anhui Science and Technology Program (090518026)+1 种基金Natural Science Foundation of Fuyang Normal College (2011CXY04,2009FSKJ04,2011HJJC02ZD,2011HJJC01ZD,2011HJJC05YB,2011HJJC04YB,2011HJJC03YB,2010FSKJ01ZD)Open fund of State Key Laboratory of Rare Earth Materials Chemistry and Applications (RE201101)
文摘The rare earth complexes Tb（o-BrBA）3,Tb（m-BrBA）3 and Tb（p-BrBA）3 were synthesized using o-,m-,p-bromo benzoic acids（2-bromo benzoic acid,3-bromo benzoic acid and 4-bromo benzoic acid） as ligand,respectively.The UV spectra showed that the absorption ability of Tb（m-BrBA）3 was the strongest.However,the fluorescent intensity of Tb（o-BrBA）3 was the weakest.The effect of the molecular structure,the energy level of Tb3＋ and energy transfer efficiency from ligands to Tb3＋ were discussed to explain the experimental results.The results indicated that,due to the large atomic radius of bromine,the steric effect caused by the different substitution bromine on the benzene ring might strongly affect the bond length formed by the coordination atoms and Tb3＋.The longer the bond length was,the lower the efficiency of energy transfer was,and the weaker the fluorescent intensity was.
基金Project supported by the Shanghai Science and Technology Innovation Action(Grant No.22dz1208700).
文摘Pulse echo accumulation is commonly employed in coherent Doppler wind LiDAR(light detection and ranging)under the assumption of steady wind.Here,the measured spectral data are analyzed in the time dimension and frequency dimension to cope with the temporal wind shear and achieve the optimal accumulation time.A hardware-efficient algorithm combining the interpolation and cross-correlation is used to enhance the wind retrieval accuracy by reducing the frequency sampling interval and then reduce the spectral width calculation error.Moreover,the temporal broadening effect and spatial broadening effect are decoupled according to the strategy we developed.
基金National Technology Research and Development Program of the Ministry of Science and Technology of China under Grant No.2015BAK17B03National Natural Science Foundation of China(General Program)under Grant No.51278152+1 种基金National Science & Technology Pillar Program(2015BAK17B06)Program for Innovation Research Team in China Earthquake Administration
文摘Due to the randomness of earthquake wave magnitude and direction, and the uncertain direction of strong axis and weak axis in the construction of engineering structures, the effect of the direction of ground motion on a structure are studied herein. Ground motion records usually contain three vertical ground motion data, which are obtained by sensors arranged in accordance with the EW （East -West） direction, NS （South- North） direction and perpendicular to the surface （z） direction, referring to the construction standard of seismic stations. The seismic records in the EW and NS directions are converted to Cartesian coordinates in accordance with the rotation of θ = 0°-180°, and consequently, a countless group of new ground motion time histories are obtained. Then, the characteristics of the ground motion time history and response spectrum of each group were studied, resulting in the following observations： （1） the peak and phase of ground motion are changed with the rotation of direction θ, so that the direction θ of the maximum peak ground motion can be determined; （2） response spectrum values of each group of ground motions change along with the direction θ, and their peak, predominant period and declining curve are also different as the changes occur; then, the angle θ in the direction of the maximum peak value or the widest predominant period can be determined; and （3） the seismic response of structures with different directions of ground motion inputs has been analyzed under the same earthquake record, and the results show the difference. For some ground motion records, such as the Taft seismic wave, these differences are significant. Next, the Lushan middle school gymnasium structure was analyzed and the calculation was checked using the proposed method, where the internal force of the upper space truss varied from 25% to 28%. The research results presented herein can be used for reference in choosing the ground motion when checking the actual damage to structures following earthquakes and explaining the seismic damage. Meanwhile, it also provides a reference value for research into the most severe ground motion.
基金supported by the National Key R&D Project of China(No.2017YFC0602100)the National Natural Science Foundation of China(No.41774147)Sichuan Science and Technology Support Program(No.2015GZ0272)
文摘The full-spectrum least-squares(FSLS) method is introduced to perform quantitative energy-dispersive X-ray fluorescence analysis for unknown solid samples.Based on the conventional least-squares principle, this spectrum evaluation method is able to obtain the background-corrected and interference-free net peaks, which is significant for quantization analyses. A variety of analytical parameters and functions to describe the features of the fluorescence spectra of pure elements are used and established, such as the mass absorption coefficient, the Gi factor, and fundamental fluorescence formulas. The FSLS iterative program was compiled in the C language. The content of each component should reach the convergence criterion at the end of the calculations. After a basic theory analysis and experimental preparation, 13 national standard soil samples were detected using a spectrometer to test the feasibility of using the algorithm. The results show that the calculated contents of Ti, Fe, Ni, Cu, and Zn have the same changing tendency as the corresponding standard content in the 13 reference samples. Accuracies of 0.35% and 14.03% are obtained, respectively, for Fe and Ti, whose standard concentrations are 8.82% and 0.578%, respectively. However, the calculated results of trace elements (only tens of lg/g) deviate from the standard values. This may be because of measurement accuracy and mutual effects between the elements.
文摘The article compares the IR absorption spectra of the gases of the Earth’s atmosphere with frequencies, close to the frequency of the maximum of thermal radiation of human. It is shown that such a gas is ozone. Being in the transparency window of the atmosphere, it emits absorbed thermal radiation from the Earth. This radiation, in turn, gets to maximum heat absorption (radiation) of a human, and being with it in resonance, fuels him with energy. In larger cities this nourishment is weakened because of the smog due to the strong scattering of Earth radiation and ozone. Thus, the “greenhouse ozone” as a natural source of infrared radiation has beneficial effect on human.
文摘This case presents a rarely seen combination of two Cocaine-induced syndromes occurring simultaneously. Levamisole-adultered cocaine leads to Levamisole-induced Vasculitis (LIV), while cocaine’s vasoconstrictive effect causes destruction of the osteo-cartilaginous structures of nose called Cocaine-induced midline destructive lesions (CIMDL). This case raises awareness of a new pattern of recognition in order to avoid misdiagnosis. We present a case of a 51-year-old male cocaine user who developed severe left-sided ear pain and yellowish secretions with circular necrotic lesions in the nose, right earlobe, and dorsum of feet bilaterally. An extensive workup to assess purpuric lesions’ etiology, including vasculitis, collagen vasculitides, anti-phospholipid syndrome, hypercoagulable state and infectious process, was performed and found negative. He developed bilateral tympanic membrane perforation and purpuric necrotic skin lesions, at the same time, due to CIMDL and LIV, respectively. These two syndromes rarely present simultaneously in a patient. This case report exhibits a new Cocaine-induced clinical presentation that will help hospitalists recognize the disease and avoid misdiagnosis leading to unnecessary tests, prolonged hospitalization, and higher healthcare costs. Diagnosis is challenging, as it consists of establishing a temporal relationship between cocaine ingestion and symptoms’ onset. This disease usually has a benign progression because symptoms frequently resolve without intervention.
基金National Natural Science Foundation of China for Excellent Young Scholars under Grant No.51422801National Natural Science Foundation of China under Key Program 51338001Beijing Natural Science Foundation of China under Key Program:8151003
文摘Many studies have indicated that structural strain will be significantly influenced by temperature variations,and a good understanding of the effect of temperature on structural strain is essential.A structural health monitoring system has been installed in a typical Tibetan timber building to measure the structural strains and ambient temperature since 2012.This paper presents the correlation between temperature and strain data from the monitored structure.A method combining singular spectrum analysis and polynomial regression is proposed for modeling the temperature induced strains in the structure.Singular spectrum analysis is applied to smooth the temperature data,and the correlation between the resulting temperature time series and the measured strains is obtained by polynomial regression.Parameters of the singular spectrum analysis and the regression model are selected to have the least regression error.Results show that the proposed method has both good reproduction and prediction capabilities for temperature induced strains,and that the method is accurate and effective for eliminating the effect of temperature from the measured strain.A standardized Novelty Index based on the residual strain is also used for the condition assessment of the structure.
基金sponsored by the China National Special Fund for Earthquake Scientific Research in Public Interest(Grant No.201408002)Earthquake Science and Technology Spark Plan of China Earthquake Administration(XH14061Y)
文摘The explicit finite element analysis method combined with the artificial transmitting boundary theory is performed to evaluate the adjacent terrain effects on ground motion,and the influence of the distance between adjacent terrains on the topographical amplification effects on ground motion is studied. The results show that:( 1) Compared to the case of a single hill,the presence of adjacent hills has little effect on the shape of the spectral ratio curve,but has a significant effect on the value of spectral ratio,which is dependent on the locations of observation points.( 2) The presence of adjacent hills has a greater effect on high-frequency ground motion,and with the increase of the distance between adjacent hills,such an effect weakens gradually,and the effect of the composite topography combined with multiple hills on ground motion gradually approaches that of a single hill.
文摘Combined with irregular wave-maker, the growing process of Wave Energy Spectrum in shallow water can be studied in wind wave channel on different water depth conditions, and its transformation characteristics and rules can be obtained.
