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Multi-level effects in the high-order harmonic generation driven by intense frequency-comb laser fields
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作者 赵迪 蒋臣威 李福利 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期256-261,共6页
High harmonic generation(HHG) driven by intense frequency-comb laser fields can be dramatically enhanced via multiphoton resonance by tuning the carrier-envelope phase(CEP) shift, without increasing the driving in... High harmonic generation(HHG) driven by intense frequency-comb laser fields can be dramatically enhanced via multiphoton resonance by tuning the carrier-envelope phase(CEP) shift, without increasing the driving intensity. However,the multiphoton-resonant enhancement(MRE) factor in the realistic atomic hydrogen is much smaller than that in a twolevel system. To study the deviation, we present a theoretical investigation of the multiphoton resonance dynamics of three-level systems driven by intense frequency-comb laser fields. The many-mode Floquet theorem(MMFT) is employed to provide a nonperturbative and exact treatment of the interaction between the quantum system and the laser fields. The investigations show that the dipole interaction of a two-level system with the third level affects the multiphoton resonance dynamics and enhances the HHG spectra. It is the dipole interaction of the excited level of the two-level system with other levels that results in the smaller MRE factor in the realistic atomic system. 展开更多
关键词 high-order harmonic generation frequency-comb laser fields multi-level effects
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 China’s COASTAL areas. RELATIVE SEA level RISE environmental effect resource effect
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Influence of Doppler broadening and spontaneously generated coherence on propagation effect in a quasi lambda-type four-level system 被引量:1
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作者 Liu Zhong-Bo Liang Ying +1 位作者 Jia Ke-Ning Fan Xi-Jun 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期322-332,共11页
In this paper we study influences of Doppler broadening, spontaneously generated coherence, and other system parameters on propagation effect in a quasi lambda-type four-level atomic system. It is shown that when the ... In this paper we study influences of Doppler broadening, spontaneously generated coherence, and other system parameters on propagation effect in a quasi lambda-type four-level atomic system. It is shown that when the Doppler broadening is present, generally speaking, the values of gain and intensity of lasing without inversion (i.e. the probe field) in the co-propagating probe and driving fields case are much larger than those in the counter-propagating case; considerably larger gain and intensity of lasing without inversion than those without the Doppler broadening can be obtained by choosing appropriate values of the Doppler broadening width and spontaneously generated coherence strength. The gain and intensity of lasing without inversion increase with the increase of spontaneously generated coherence strength; when spontaneously generated coherence is present, much larger gain and intensity of lasing without inversion than those in the case without spontaneously generated coherence can be obtained. Choosing suitable values of the probe detuning, Rabi frequencies of the driving and pump fields at the entrance of the medium also can remarkably enhance the gain and intensity of lasing without inversion. 展开更多
关键词 four-level system propagation effect spontaneously generated coherence Doppler broadening lasing without inversion
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Effect of Konjac Food on Blood Glucose Level in Patients with Diabetes 被引量:2
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作者 HUANG CHENG-YU ZHANG MAO-YU +10 位作者 PENG SHU-SHENG HONG JUN-RONG WANG XU JIANG HUIJUN ZHANG FULIN BAI YUNXIANG LIANG JINZHONG Yu YERONG LUO ZHAOTIAN ZHANG XIANGXUN AND ZHOU ZANCHENG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1990年第2期123-131,共9页
Seventy-two type II diabetic subjects were given Konjac food for 65 days. The data analyzed by multiple F test indicate that the fasting blood glucose (FBG) and the 2-h postprandial blood glucose (PBG) on the 30th and... Seventy-two type II diabetic subjects were given Konjac food for 65 days. The data analyzed by multiple F test indicate that the fasting blood glucose (FBG) and the 2-h postprandial blood glucose (PBG) on the 30th and the 65th days after the food was ingested were significantly reduced (P = 0.001, P < 0.001, respectively), as was the glycosylated hemoglobin level at the end of the trial (P < 0.05). The final FBG and PBG of the subjects with initial FBG-O >200 mg% decreased on the average by 51.8 and 84.6 mg%. respectively; those with FBG-0 150-200 mg% decreased by 24.1 and 68.7 mg%; and those with FBG-O < 150 mg% decreased by 4.8 and 21.4 mg%. No significant changes in blood lipid indexes were observed, except that the triglycer-ide values of subjects with hypertriglyceridemia (>200 mg%) significantly decreased by 118.7 mg%. It was concluded that Konjac food is very useful in the prevention and treatment of hyperglycemia. (C)1990 Academic Press. Inc. 展开更多
关键词 effect of Konjac Food on Blood Glucose level in Patients with Diabetes
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Fermi level pinning effects at gate–dielectric interfaces influenced by interface state densities 被引量:1
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作者 洪文婷 韩伟华 +2 位作者 吕奇峰 王昊 杨富华 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期443-447,共5页
The dependences of Fermi-level pinning on interface state densities for the metal-dielectric, ploycrystalline silicon-dielectric, and metal silicide-dielectric interfaces are investigated by calculating their effectiv... The dependences of Fermi-level pinning on interface state densities for the metal-dielectric, ploycrystalline silicon-dielectric, and metal silicide-dielectric interfaces are investigated by calculating their effective work functions and their pinning factors. The Fermi-level pinning factors and effective work functions of the metal-dielectric interface are observed to be more susceptible to the increasing interface state densities, differing significantly from that of the ploycrystalline silicon-dielectric interface and the metal silicide-dielectric interface. The calculation results indicate that metal silicide gates with high-temperature resistance and low resistivity are a more promising choice for the design of gate materials in metal-oxide semiconductor(MOS) technology. 展开更多
关键词 interface state density Fermi-level pinning MIS structure effective work function
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Effect of Quasi-Fermi Level on the Degree of Electron Spin Polarization in GaAs
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作者 滕利华 牟丽君 王霞 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期41-44,共4页
With spin-polarized-dependent band gap renormalization effect taken into account, the energy-dependent evolu- tion of electron spin polarization in GaAs is calculated at room temperature and at a low temperature of 1O... With spin-polarized-dependent band gap renormalization effect taken into account, the energy-dependent evolu- tion of electron spin polarization in GaAs is calculated at room temperature and at a low temperature of 1OK. We consider the exciting light with right-handed circular polarization, and the calculation results show that the degree of electron spin polarization is dependent strongly on the quasi-Fermi levels of |1/2) and |- 1/2) spin conduction bands. At room temperature, the degree of electron spin polarization decreases sharply from 1 near the bottom of the conduction band, and then increases to a stable value above the quasi-Fermi level of the |- 1/2) band. The greater the quasi-Fermi level is, the higher the degree of electron spin polarization with excessive en- ergy above the quasi-Fermi level of the |- 1/2) band can be achieved. At low temperature, the degree of electron spin polarization decreases from 1 sharply near the bottom of the conduction band, and then increases with the excessive energy, and in particular, up to a maximum of i above the quasi-Fermi level of the |1/2) band. 展开更多
关键词 of IT as effect of Quasi-Fermi level on the Degree of Electron Spin Polarization in GaAs in on
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Optimal entropy squeezing sudden generation and its control for an effective two-level moving atom entanglement with the two-mode coherent fields 被引量:2
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作者 刘小娟 周元俊 方卯发 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2307-2313,共7页
From the viewpoint of quantum information, this paper proposes a concept and a definition of the atomic optimal entropy squeezing sudden generation (AOESSG) for the system of an effective two-level moving atom which... From the viewpoint of quantum information, this paper proposes a concept and a definition of the atomic optimal entropy squeezing sudden generation (AOESSG) for the system of an effective two-level moving atom which entangles with the two-mode coherent fields. It also researches the relationship between the AOESSG and entanglement sudden death of the atom-fields, and discusses the influences of atomic initial state on the AOESSG and obtains the system parameter which controls the AOESSG. 展开更多
关键词 optical entropy squeezing sudden generation effective two-level moving atom entanglement sudden death
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Effects of topiramate and carbamazepine on thyroid hormone level in adults with epilepsy 被引量:1
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作者 Liang Yu, Yulan Huang, Hongbin Sun, Jie Liu, Fei Xu, Xiaoping Wang Sichuan Academy of Medical Sciences Department of Neurology, Sichuan Provincial People’s Hospital, Chengdu 610072, Sichuan Province, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第8期706-709,共4页
BACKGROUND: It has been demonstrated that traditional antiepileptics, such as phenytoin, carbamazepine (CBZ), phenobarbital, etc., can result in the decrease of thyroid hormone of epileptic patients. However, there is... BACKGROUND: It has been demonstrated that traditional antiepileptics, such as phenytoin, carbamazepine (CBZ), phenobarbital, etc., can result in the decrease of thyroid hormone of epileptic patients. However, there is still no sufficient evidence for the studies about the effect of new-type antiepileptics, such as topiramate (TPM), on thyroid hormones. OBJECTIVE: To observe the effects of TPM and CBZ on the level of thyroid hormones in serum of adults with epilepsy. DESIGN: A comparative observation. SETTING: Department of Neurology, Sichuan Provincial People's Hospital. PARTICIPANTS: Totally 100 outpatients or inpatients newly diagnosed to have epilepsy were selected from the Department of Neurology, Sichuan Provincial People's Hospital from July 2003 to August 2005, including 60 males and 40 females, aged 18-70 years. All the patients were accorded with the standard for the classification of epilepsy set by International League Against Epilepsy (ILAE) in 1981; Had been Informed and agreed with the detection; Had no history of thyroid gland disease; Had not taken any drugs could affect the thyroid function. Meanwhile, 40 adult healthy examinees were selected from our hospital as the control group, including 24 males and 16 females, aged 18-65 years. METHODS: ① The 100 epileptic patients were randomly divided into TPM group (n =50) and CBZ group (n =50), and they were treated with TPM (Xian-Janssen Pharmaceutical, Ltd.; Batch number: 03AS032, Norm: 25 mg/tablet) and CBZ (Shanghai Sunve Pharmaceutical Co., Ltd.; Batch number: 030201, Norm: 100 mg/tablet) respectively. The initial dosage of TPM was 25 mg per day, increased by 25 mg every week, the objective dosage of 100-200 mg per day was maintained when the symptoms were satisfactorily controlled. The dosage of CBZ was 6-8 mg/kg per day. All the patients were administrated for 1 year. ② The serum levels of total thyroxine (TT4), free thyroxine (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3) and thyroid stimulating hormone (TSH) in the epileptic patients were detected by means of chemiluminescence before treatment and at 3, 6 and 12 months after treatment respectively. ③Standards for judging curative effects: Controlled by without seizure, the frequency of seizure reduced by ≥ 75% was taken as significant effect, reduced by 50%-74% as effect, and reduced by < 49% as invalid, whereas increased by more than 20% was taken as aggravation. ④ The intergroup and intragroup differences of the measurement data were compared by the analysis of variance and paired t test respectively. MAIN OUTCOME MEASURES: Serum levels of thyroid hormones before treatment and at different time points after treatment of TPM and CBZ. RESULTS: All the 100 epileptic patients and 40 healthy subjects were involved in the analysis of results. ① Changes of serum levels of thyroid hormones: The serum levels of TT3, TT4, FT3, FT4 and TSH were close between the epileptic patients and normal subjects before treatment (P > 0.05). In the CBZ group, the serum levels of FT4 at 3, 6 and 12 months after treatment [(16.87±3.77), (16.34±3.98) , (16.97±3.95) pmol/L] were significantly decreased as compared with those before treatment [(18.00±3.54) pmol/L, t =2.74, 3.50, 2.26, P < 0.05]; The levels of TT3 at 3, 6 and 12 months [(2.09±0.54), (1.99±0.49), (1.84±0.47) nmol/L] were significantly decreased as compared with those before treatment [(2.22±0.63) nmol/L, t =2.73, 2.78, 5.18, P < 0.05]. The levels of TT3 at 6 and 12 months [(109.65±23.98), (107.72±23.90) nmol/L] were significantly decreased as compared with those before treatment [(118.98±28.48) nmol/L, t =3.11, 3.30, P < 0.05]. TT4 level in serum at 3 months and the levels of FT3 and TSH at each time point after CBZ treatment had no obvious changes as compared with those before treatment (P > 0.05). In the TPM group, the levels of thyroid hormones at each time point had no obvious changes as compared with those before treatment (P > 0.05). ② Curative effects: Of the 100 epileptic patients, it was controlled in 12 cases, significantly effective in 30 cases, effective in 39 cases and invalid in 19 cases, the total effective rate was 81% (81/100). CONCLUSION: CBZ treatment can lead to the decreases of thyroid hormones in adult epileptic patients. Epilepsy itself and TPM treatment cannot change the thyroid hormones in adult epileptic patients, which suggests that TPM treatment is safer for the thyroid function of adult epileptic patients. 展开更多
关键词 CBZ effects of topiramate and carbamazepine on thyroid hormone level in adults with epilepsy
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Bismuth Effects on Electronic Levels in GaSb(Bi)/AlGaSb Quantum Wells Probed by Infrared Photoreflectance
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作者 陈熙仁 宋禹忻 +6 位作者 朱亮清 祁镇 朱亮 查访星 郭少令 王庶民 邵军 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期127-130,共4页
GaSb(Bi)/Alo.2Gao.sSb single quantum wells are characterized by a Fourier transform infrared spectrometer- based photoreflectance method at 77K. Spatially direct and indirect transitions between the electronic level... GaSb(Bi)/Alo.2Gao.sSb single quantum wells are characterized by a Fourier transform infrared spectrometer- based photoreflectance method at 77K. Spatially direct and indirect transitions between the electronic levels at and above the effective band gap are well resolved. The shifts of the electronic levels with Bi incorporation are identified quantitatively. The results show that the upshift of the valence band edge is clarified to be dominant, while the Bi-induced downshift of the conduction band edge does exist and contributes to the band gap reduction in the GaSbBi quantum-well layer by (29±6)%. 展开更多
关键词 Bismuth effects on Electronic levels in GaSb
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Effective Dose Levels from Computed Tomography of the Head during Contrast Studies in Nigeria 被引量:2
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作者 Thomas Adejoh Nzotta Chukwuemeka Christian +1 位作者 Flavious Bobuin Nkubli Joseph Zira Dlama 《Health》 2015年第8期915-919,共5页
Background: Diagnostic reference levels for a number of common diagnostic radiological examinations against which individual centres could compare their performance have been recommended by relevant international agen... Background: Diagnostic reference levels for a number of common diagnostic radiological examinations against which individual centres could compare their performance have been recommended by relevant international agencies. Due to variations in different populations globally, local and national diagnostic reference levels are more reliable. To the best of our knowledge, no centre-specific study has been carried out and national surveys are not available. Objective: To establish a preliminary local and national diagnostic reference level in Nigeria. Methods: A pro-spective and cross-sectional study involving 30 conscious paediatrics and adult patients referred for head computed tomography scan. They were positioned supine and scanned according to the standard protocol for head computed tomography with manual mA selection. The total dose-length products were recorded at the end of the pre-contrast and post-contrast sequences respectively. The pre-contrast dose was taken into cognizance in the determination of the post-contrast value. The effective dose was established by multiplying the dose-length product by 0.0023 mSv.mGy-1.cm-1, a conversion coefficient for brain tissue adopted from the European Commission. Statistical Package for Social Sciences version 17.0 was used to analyze the data. Results: 30 paediatrics and adult patients of mixed gender participated in the study. Their ages ranged from 1 to 74 years with a mean age of 41.47 ± 23.30 years. The pre-contrast effective dose ranged from 1.93 mSv to 3.32 mSv with mean of 2.56 ± 0.51 mSv and 75th percentile of 3.11 mSv while the post-contrast effective dose ranged from 4.06 mSv to 6.97 mSv with mean of 5.27 ± 0.97 mSv and 75th percentile of 6.13 mSv. The mean effective dose from this work and two other isolated studies was 3.0 mSv. Conclusion: Although our quantified doses are below threshold limits for occupational exposures they are higher than the recommended level for the public. A further optimization of scanning protocols by the radiographers could lower the effective dose for patients undergoing contrast head computed tomography in our centre and in the country. 展开更多
关键词 effective DOSE Diagnostic Reference level RADIOGRAPHER COMPUTED Tomography HEAD
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Mechanical effects of light on the ■-type three-level atom in a high-finesse optical cavity
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作者 刘利伟 谭磊 黄刚 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期377-384,共8页
A theoretical study is carried out for the modification and implication of the effect on the type three level atom in a high-finesse optical cavity driven by light field including spontaneous emission and the cavity d... A theoretical study is carried out for the modification and implication of the effect on the type three level atom in a high-finesse optical cavity driven by light field including spontaneous emission and the cavity decay. Analytic expressions for the dipole force, the friction force, the optical potentials and the friction coefficient are obtained. Then the numerical and graphical methods are used to investigate the friction coefficient with the controlling parameters. It is shown that the friction coefficient is strongly dependent on the controlling parameters. The cooling rate can increase by one order of magnitude more than that of a two-level atomic system. The reason can be given using the dressed states and the Sisyphus cooling mechanism, which would stimulate further experimental investigations. 展开更多
关键词 three-level atom mechanical effects high finesse optical cavity
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Study on Communication Effect of Food Safety Risk in Social Media:the Influence of Response Effort Level on Consumption Willingness Change 被引量:1
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作者 Wenlin FANG Fengyuan SHI 《Asian Agricultural Research》 2019年第3期11-16,29,共7页
By constructing influence model for communication effect of food safety risk in social media environment,the influences of different response manners taken by relevant enterprises on consumers' cognition and purch... By constructing influence model for communication effect of food safety risk in social media environment,the influences of different response manners taken by relevant enterprises on consumers' cognition and purchasing intention are analyzed,and influence mechanisms of response effort level,interaction and content reliability on consumers' attitudes are revealed. Based on quasi-experimental study with three kinds of response effort levels,it is found that content reliability,interaction and effort degree of enterprise response under negative information of food safety event have significant impacts on communication effect and consumers' purchasing intention. 展开更多
关键词 Food safety COMMUNICATION effect Social media EFFORT level PURCHASE WILLINGNESS
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Effect of Increasing CO_2 on the Stratospheric Level of CO and O_3
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作者 L.S.Hingane 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第3期390-392,共3页
Production and destruction processes of carbon monoxide (CO) and ozone (O3) are examined in the light of increasing amount of atmospheric carbon dioxide (CO2). It is found that doubling of CO2 will increase the strato... Production and destruction processes of carbon monoxide (CO) and ozone (O3) are examined in the light of increasing amount of atmospheric carbon dioxide (CO2). It is found that doubling of CO2 will increase the stratospheric concentration of CO and will have positive effect on O3 concentration. 展开更多
关键词 In effect of Increasing CO2 on the Stratospheric level of CO and O3 CO
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Stark and Kerr Effects on the Dynamics of Moving N-Level Atomic System
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作者 Syed Jamal Anwar Mohammed Ramzan +1 位作者 Mohammed Usman Mohammed Khalid Khan 《Journal of Quantum Information Science》 2019年第1期22-40,共19页
We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linea... We have investigated numerically the dynamics of quantum Fisher information (QFI) and quantum entanglement (QE) for N-level atomic system interacting with a coherent field in the presence of Kerr (linear and non-linear medium) and Stark effects. It is observed that the Stark and Kerr effects play a prominent role during the time evolution of the quantum system. The evolving quantum Fisher information (QFI) is noted as time grows under the non-linear Kerr medium contrary to the QE for higher dimensional systems. The effect of non-linear Kerr medium is greater on the QE as we increase the value of Kerr parameter. However, QFI and QE maintain their periodic nature under atomic motion. On the other hand, linear Kerr medium has no prominent effects on the dynamics of N-level atomic system. Furthermore, it has been observed that QFI and QE decay soon under the influence of Stark effect. In short, the N-level atomic system is found prone to the change of the Kerr medium and Stark effect for higher dimensional systems. 展开更多
关键词 QFI KERR effect STARK effect N-level ATOMIC System
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Radio Frequency Environment Effect Algorithms and Implementation in Signal-level Radar System Simulation
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作者 WANG Quanmin WANG Chuncai GUO Gang HUANG Kedi 《系统仿真技术》 2009年第1期45-54,共10页
In radar system simulation,the reliability of simulation results depends not only on radar and target models,but also on radio frequency (RF) environment models,including clutter,multipath,diffraction,atmosphere refra... In radar system simulation,the reliability of simulation results depends not only on radar and target models,but also on radio frequency (RF) environment models,including clutter,multipath,diffraction,atmosphere refraction and attenuation.In traditional radar function simulation,all of these factors are grouped into a single pattern-propagation factor and can only give limited information for radar models.In signal-level simulation,radar models require simulated echoes should include information such as delay,doppler frequency,polarization,etc.By discussing and analyzing the principles and algorithms of RF environment effects (clutter,multipath,diffraction,atmosphere refraction and attenuation),this paper is supposed to provide a general RF environment model in signal-level.Algorithms for the Weibull clutter with Gaussian power spectral density (PSD) is discussed;A standard multipath and diffraction algorithm is analyzed,and the spherical earth and knife edge(SEKE)diffraction algorithm is introduced;The ray-tracing algorithm and the effective earth model are discussed;Algorithms for the absorption of oxygen and vapor are introduced;For certain algorithms,some practical advice is given.Finally,an object-oriented RF environment effects model is implemented,which has been dedicatedly designed for signal-level simulations and can provide relatively authentic simulated RF environment for the signal-level simulation of radar systems.Two simulation examples including clutter model and multipath and diffraction model are carried out and analyzed. 展开更多
关键词 雷达 系统仿真技术 偏振 射线追踪算法 计算方法
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Quantum Fisher Information of Two-Level Atomic System under the Influence of Thermal Field, Intrinsic Decoherence, Stark Effect and Kerr-Like Medium
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作者 S. Jamal Anwar M. Ramzan +1 位作者 M. Usman M. Khalid Khan 《Journal of Quantum Information Science》 2021年第1期24-41,共18页
In this paper, we have proposed the numerical calculations to study the quantum entanglement (QE) of moving two-level atom interacting with a coherent and the thermal field influenced by intrinsic decoherence (ID), Ke... In this paper, we have proposed the numerical calculations to study the quantum entanglement (QE) of moving two-level atom interacting with a coherent and the thermal field influenced by intrinsic decoherence (ID), Kerr medium (non-linear) and the Stark effect. The wave function of the complete system interacting with a coherent and the thermal field is calculated numerically affected by ID, Kerr (non-linear) and Stark effects. It has been seen that the Stark, Kerr, ID and the thermal environment have a significant effect during the time evolution of the quantum system. Quantum Fisher information (QFI) and QE decrease as the value of the ID parameter is increased in the thermal field without the atomic movement. It is seen that QFI and von Neumann entropy (VNE) show an opposite and periodic response in the presence of atomic motion. The non-linear Kerr medium has a more prominent and significant effect on the QE as the value of the Kerr parameter is decreased. At smaller values of the non-linear Kerr parameter, the VNE increases, however, QFI decreases, so QFI and VNE have a monotonic connection with one another. As the value of the Kerr parameter is increased, the effect of non-linear Kerr doesn’t stay critical on both QFI and QE. However, a periodic response of QE is seen because of the atomic movement which becomes modest under natural impacts. Moreover, it has been seen that QFI and QE rot soon at the smaller values of the Stark parameter. However, as the value of the Stark parameter is increased, the QFI and QE show periodic response even when the atomic movement is absent. 展开更多
关键词 Quantum Fisher Information (QFI) Intrinsic Decoherence (ID) Thermal Environment Two-level Atomic System Kerr and Stark effect
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Level Set方法在地面效应数值模拟中的应用 被引量:1
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作者 何琨 陈坚强 毛枚良 《应用力学学报》 CAS CSCD 北大核心 2013年第3期328-333,471,共6页
利用Level Set方法隐式捕捉界面并能处理复杂的物质界面及其拓扑结构变化(如合并、交叉、破碎等)情况的优势,基于可压缩N-S方程的预处理技术,采用基于界面两侧介质黎曼关系的修正虚拟流体方法对介质边界进行处理;将只能应用于可压缩流... 利用Level Set方法隐式捕捉界面并能处理复杂的物质界面及其拓扑结构变化(如合并、交叉、破碎等)情况的优势,基于可压缩N-S方程的预处理技术,采用基于界面两侧介质黎曼关系的修正虚拟流体方法对介质边界进行处理;将只能应用于可压缩流动界面模拟的修正虚拟流体方法推广应用于不可压缩流动问题的模拟,数值模拟了气-水运动界面与近水面飞行器的相互影响规律。通过与将水面视为对称面的简化模型对比发现:利用自由运动界面模型计算的NACA6409翼型升力较小,能更准确地反映飞行器流场对水面形状的影响,其结果更为符合实际;文中还对比了翼型距水面不同高度时的结果,得到了翼型受水面影响的强弱与翼型距水面的高度成反比的结论。 展开更多
关键词 地面效应 level SET方法 修正虚拟流体方法 预处理方法
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实践视域下英国T Level课程建设的研究与探索 被引量:1
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作者 李玲玲 许洋 康校博 《比较教育学报》 CSSCI 北大核心 2023年第3期123-133,共11页
T Level课程是以职业教育为导向的全日制课程体系,是英国中学阶段与A Level课程及学徒制并驾齐驱的“第三条道路”。本研究基于实践背景,从经济、市场、社会三个维度分析英国T Level课程建设的现实动因。结合具体教学实践,从招生指向、... T Level课程是以职业教育为导向的全日制课程体系,是英国中学阶段与A Level课程及学徒制并驾齐驱的“第三条道路”。本研究基于实践背景,从经济、市场、社会三个维度分析英国T Level课程建设的现实动因。结合具体教学实践,从招生指向、课程设置、师资配置、实习实践四个方面探讨T Level课程建设的实践路径。T Level课程建设产生的政策效应包括强化雇主在技能人才培养中的主导地位、建立学术与技术路径之间自由转换机制、明确职业地图与职业坐标的相对应关系、确立以能力为导向的多元化学业评价标准。反思T Level课程建设,发现有其独特的价值意蕴,也面临争议挑战,能为我国职业教育提供经验启示。 展开更多
关键词 英国 T level 课程建设 政策效应
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Effects of Sub-chronic Intoxication of 1,8-cineole on Blood Biochemical Indexes of Mice 被引量:1
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作者 Du Yonghua Wang Chuan +5 位作者 Zhou Lijun Zhang Ping Wei Qin Yin Zhongqiong Jiang Qinjiu Jiang Jihong 《Animal Husbandry and Feed Science》 CAS 2015年第3期167-170,173,共5页
[ Objective] Effects of sub-chronic intoxication of 1,8-cineole on body weights, routine blood indexes and biochemical indexes of mice were investigated. [Method] One hundred and sixty mice with body weights of 15 -17... [ Objective] Effects of sub-chronic intoxication of 1,8-cineole on body weights, routine blood indexes and biochemical indexes of mice were investigated. [Method] One hundred and sixty mice with body weights of 15 -17 g were randomly divided into four groups (forty mice per group). Mice were injected to 1, 8 - cineole with doses of 192.45,64. 15 and 21.38 mg/kg body weight ( test groups) and the water solution of tween-80 with a volume fraction of 0.5% ( control group) respectively. Each mouse was administered orally at the dose of 0.2 mL per 10 g body weight once a day consecutively for 90 d. The body weight, routine blood indexes and serum biochemical indexes of mice were determined on the 30^th d, 60^th d, 90^th d and the 30^th d after stopping the administration of 1,8-cineole. [ Result] The effects of 1, 8-cineole on the body weight, routine blood indexes and serum biochemical indexes of mice with the doses of 64.15 and 21.38 mg/kg body weight had no statistically significant difference compared with the control group (P 〉0.05 ). 1, 8-cineole with the dose of 192.45 mg/kg body weight exhibited different influences on routine blood indexes and serum biochemical indexes of mice after the oral administration of 1,8-cineole for 60 d and 90 d, and statistically significant differences in many blood biochemical indexes were observed (P 〈 0.05 ). However, the differences in routine blood indexes and serum biochemical indexes were not statistically significant between the test groups and the control group at the 30'h d after stopping the administration of 1, 8-cineole ( P 〉 0.05). [Condusion] 1,8-cineole had sub-chronic oral toxicity to mice. The no observed adverse effect level (NOAEL) of 1,8-cineolc was 64.15 mg/kg body weight and the lowest observed adverse effect level (LOAEL) of 1,8-cineole was 192.45 mg/kg body weight. Effects of 1, 8-cineole on blood biochemical indexes of mice were in short term and reversible. 展开更多
关键词 1 8-cineole Sub-chronic toxicity Lowest observed adverse effect level No observable adverse effect level
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Influence of Variety and Maturity Level on Natural Convective Heat Drying of Four Onion Varieties Grown in Senegal 被引量:1
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作者 Ngoné Fall Beye Cheikhou Kane +3 位作者 Nicolas Cyrille Ayessou Cheikhou Talla Abdou Sene Codou Mar Diop 《Food and Nutrition Sciences》 2018年第8期997-1013,共17页
The considerable post-harvest losses (5% to 40% depending on storage time) due to the high water content level of the onion varieties in Senegal are the main cause of the problem of access to local onion all year roun... The considerable post-harvest losses (5% to 40% depending on storage time) due to the high water content level of the onion varieties in Senegal are the main cause of the problem of access to local onion all year round. Therefore, drying is one of the techniques that can be used to solve the problem of onion perishability. This study deals with the characterization of naturally convective kinetics drying of four onion varieties in relation to their maturity level. The experiment was carried out using the gravimetric method. The Welch and Turkey statistical tests display a significant difference between the effective diffusivity coefficients depending on the maturity level within each variety and across the four varieties. The effective diffusivity coefficients of the Galmi Violet, Safari, Gandiol F1 and Orient F1varieties range from 2.18 × 10&minus;11 ± 2.69 × 10&minus;12 to 1.32 × 10&minus;10 ± 1.17 × 10&minus;11 m2&sdot;s&minus;1 at a maturity level less than 80%. When the maturity level is greater than 85%, the effective diffusivity coefficients range from 1.30 × 10&minus;11 ± 1.24 × 10&minus;12 to 8.05 × 10&minus;11 ± 8.94 × 10&minus;13 m2&sdot;s&minus;1. As far as the activation energy is concerned, the study only reveals a significant difference between the varieties whatever the maturity level is. The Galmi Violet variety stands out with an average activation energy of 66.71 ± 0.12 KJ&sdot;mol&minus;1 K&minus;1 for the maturity level below 80% and 58.74 ± 0.11 KJ&sdot;mol&minus;1 for the maturity level above 85%. For the three remaining varieties, the average activation energy ranges from 58.15 ± 0.19 to 59.12 ± 0.13 KJ&sdot;mol&minus;1 for a maturity level less than 80% whereas the rates go from 47.63 ± 0.28 to 49.96 ± 0.77 KJ&sdot;mol&minus;1 when the maturity level is greater than 85%. In summary, the higher the maturity level is, the lower the effective diffusivity coefficients will be. The same tendency was observed with the activation energy. The Galmi Violet variety represents the limitative one in case of the drying of the four varieties mix together. 展开更多
关键词 ALLIUM cepa L. DRYING Kinetics MATURITY level effective DIFFUSIVITY
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