In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, throu...In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, through computer simulation experiment were analyzed, and optimization design, through the real car collision test, make the concrete guardrail after heightening structure satisfies the requirement of </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">safety performance of current specification. The results show that the protective performance of the two guardrail schemes meets the requirements of the current guardrail evaluation standards through the computer simulation experiment. Through the optimized design of scheme 1, the actual car crash test proves that the enhanced structure of Minhua TYPE II concrete guardrail can meet the requirements of safety performance evaluation. The research results provide an important basis for the transformation of </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">guardrail and the revision of the current design of expressway in China.展开更多
<strong>Objective:</strong><span><span><span style="font-family:""><span style="font-family:Verdana;"> To study the place of simulation in the learning of n...<strong>Objective:</strong><span><span><span style="font-family:""><span style="font-family:Verdana;"> To study the place of simulation in the learning of newborn resuscitation among seventh year medical students at the University Hospital of Bogodogo in Ouagadougou, Burkina Faso. </span><b><span style="font-family:Verdana;">Material</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">Method:</span></b><span style="font-family:Verdana;"> Our study took place in the obstetrical gynaecology department of the University Hospital Centre of Bogodogo (UTH-B) from 15 December 2018 to 15 March 2019. We randomly selected two groups of students, with no stimulation. We recorded a theoretical questionnaire to all students at the beginning and then carried out two stimulation sessions at 1 month intervals in the competence laboratory of the National School of Public Health. Then we evaluated the theoretical and practical progress of the students over time. We analyzed our data through the Epi info software in version 3.5.1. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The two simulation sessions positively influenced the theoretical knowledge of neonatal intensive care for 7th year students (p = 0.0391). Neonatal resuscitation management by students is better from one simulation session to another with a statistically significant difference (p = 0.0001). </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Our study of 7th grade students showed the importance of this tool in their practical training at the University Hospital of Bogodogo. Advocacy must be organized for its acquisition in the university hospitals of Burkina Faso.</span></span></span></span>展开更多
We present a stochastic procedure to investigate the correlation spectra of quantum dot superluminescent diodes. The classical electric field of a diode is formed by a polychromatic superposition of many independent s...We present a stochastic procedure to investigate the correlation spectra of quantum dot superluminescent diodes. The classical electric field of a diode is formed by a polychromatic superposition of many independent stochastic oscillators. Assuming fields with individual carrier frequencies, Lorentzian linewidths and amplitudes we can form any relevant experimental spectrum using a least square fit. This is illustrated for Gaussian and Lorentzian spectra, Voigt profiles and box shapes. Eventually, the procedure is applied to an experimental spectrum of a quantum dot superluminescent diode which determines the first- and second-order temporal correlation functions of the emission. We find good agreement with the experimental data and a quantized treatment. Thus, a superposition of independent stochastic oscillators represents the first- and second-order correlation properties of broadband light emitted by quantum dot superluminescent diodes.展开更多
The present study is designed to simulate and study the production of single crystals of semi-organic non-linear optical Glycine Sodium Nitrate (GSN) by using hyper6 software and experimentally by slow evaporation tec...The present study is designed to simulate and study the production of single crystals of semi-organic non-linear optical Glycine Sodium Nitrate (GSN) by using hyper6 software and experimentally by slow evaporation technique. This work has investigated the molecular properties of the crystals using the density functional theory to obtain the infrared spectrum of the crystal by simulation. The FTIR investigation of growing crystal has shown that the spectrum of the GSN crystal compared to simulation evaluation is similar;the only difference is in the range of 1.9% to 2.75% of wavelength peak values. The ultraviolet experimental measurement of the GSN molecule reveals the possibility of non-linear properties due to the spectrum cutoff in the wavelength peak of 301 nm. There was a significantly positive correlation between simulation and experimental assessment.展开更多
<div style="text-align:justify;"> This study demonstrates mathematical analysis of biodegradation processes of xenobiotic polymers. A model for microbial population is based on the fact that growth rat...<div style="text-align:justify;"> This study demonstrates mathematical analysis of biodegradation processes of xenobiotic polymers. A model for microbial population is based on the fact that growth rate of microorganisms is proportional to the microbial population and consumption rate of parts of carbon sources. The model is paired with a model for weight distribution. Those models lead to inverse problems for a molecular factor and a time factor of degradation rate. Solution of the inverse problems allows us to simulate the biodegra-dation process. </div>展开更多
The stability of underground excavations has become an important issue in order to extend underground mining operations and extract deeper deposits. The increasing demand for Tin-Tungsten (Sn-W) for industry and its m...The stability of underground excavations has become an important issue in order to extend underground mining operations and extract deeper deposits. The increasing demand for Tin-Tungsten (Sn-W) for industry and its market price has created a motivation for mining companies to extract deep-seated Sn-W ore deposits in Myanmar. Thus, this paper aims to investigate the stability of underground openings, especially, the stope with considering the mining methods. To meet the objective, FLAC<sup>3D</sup> 5.0 simulation was used for the assessment of stope under different stress ratios, 0.5, 1.0, and 1.5 for two types of underground mines;Open stoping and Cut and Fill stoping. The results show that the risk of instability of stope is high under the stress ratio of <em>K</em> = 0.5 than that of <em>K</em> = 1.0 and <em>K</em> = 1.5 in both mining methods. However, the stability of the stope in open stope method is lower than that of cut-and-fill method obviously. This result shows that the appropriate mining method has to be selected for extraction of Sn-W deposit carefully in terms of the balance of safety and cost.展开更多
In recent years,an increasing number of application services are deployed in the cloud.However,the cloud platform faces unknown security threats brought by its unknown vulnerabilities and backdoors.Many researchers ha...In recent years,an increasing number of application services are deployed in the cloud.However,the cloud platform faces unknown security threats brought by its unknown vulnerabilities and backdoors.Many researchers have studied the Cyber Mimic Defense(CMD)technologies of the cloud services.However,there is a shortage of tools that enable researchers to evaluate their newly proposed cloud service CMD mechanisms,such as scheduling and decision mechanisms.To fill this gap,we propose MimicCloudSim as a mimic cloud service simulation system based on the basic functionalities of CloudSim.MimicCloudSim supports the simulation of dynamic heterogeneous redundancy(DHR)structure which is the core architecture of CMD technology,and provides an extensible interface to help researchers implement new scheduling and decision mechanisms.In this paper,we firstly describes the architecture and implementation of MimicCloudSim,and then discusses the simulation process.Finally,we demonstrate the capabilities of MimicCloudSim by using a decision mechanism.In addition,we tested the performance of MimicCloudSim,the conclusion shows that MimicCloudSim is highly scalable.展开更多
利用Deform-3D软件对AISI4340钢Ф600 mm铸坯至300 mm x 300 mm坯的开坯过程工艺参数进行了数值模拟。通过对加热温度、轧制速度、压下率、2道次压下对铸坯心部变形和材料流动影响的研究,分析了开坯成形过程中心部等效应力和材料变形特...利用Deform-3D软件对AISI4340钢Ф600 mm铸坯至300 mm x 300 mm坯的开坯过程工艺参数进行了数值模拟。通过对加热温度、轧制速度、压下率、2道次压下对铸坯心部变形和材料流动影响的研究,分析了开坯成形过程中心部等效应力和材料变形特点,获得了Ф600圆连铸坯开坯成300mm方坯的成形规律。结果表明:在1070-1140℃内,加热温度对心部的应变影响较小,变化幅度在2.3%左右。当轧制速度选1.0~2.0 m/s、总压.下量一定的情况下,先大后小更利于心部缺陷的焊合。展开更多
文摘In order to achieve the old fence of reuse, improve the safety performance of guardrail, barrier structure does not meet the requirements, make full use of the old concrete guardrail on the basis of heightening, through computer simulation experiment were analyzed, and optimization design, through the real car collision test, make the concrete guardrail after heightening structure satisfies the requirement of </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">safety performance of current specification. The results show that the protective performance of the two guardrail schemes meets the requirements of the current guardrail evaluation standards through the computer simulation experiment. Through the optimized design of scheme 1, the actual car crash test proves that the enhanced structure of Minhua TYPE II concrete guardrail can meet the requirements of safety performance evaluation. The research results provide an important basis for the transformation of </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">guardrail and the revision of the current design of expressway in China.
文摘<strong>Objective:</strong><span><span><span style="font-family:""><span style="font-family:Verdana;"> To study the place of simulation in the learning of newborn resuscitation among seventh year medical students at the University Hospital of Bogodogo in Ouagadougou, Burkina Faso. </span><b><span style="font-family:Verdana;">Material</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">Method:</span></b><span style="font-family:Verdana;"> Our study took place in the obstetrical gynaecology department of the University Hospital Centre of Bogodogo (UTH-B) from 15 December 2018 to 15 March 2019. We randomly selected two groups of students, with no stimulation. We recorded a theoretical questionnaire to all students at the beginning and then carried out two stimulation sessions at 1 month intervals in the competence laboratory of the National School of Public Health. Then we evaluated the theoretical and practical progress of the students over time. We analyzed our data through the Epi info software in version 3.5.1. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The two simulation sessions positively influenced the theoretical knowledge of neonatal intensive care for 7th year students (p = 0.0391). Neonatal resuscitation management by students is better from one simulation session to another with a statistically significant difference (p = 0.0001). </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Our study of 7th grade students showed the importance of this tool in their practical training at the University Hospital of Bogodogo. Advocacy must be organized for its acquisition in the university hospitals of Burkina Faso.</span></span></span></span>
文摘We present a stochastic procedure to investigate the correlation spectra of quantum dot superluminescent diodes. The classical electric field of a diode is formed by a polychromatic superposition of many independent stochastic oscillators. Assuming fields with individual carrier frequencies, Lorentzian linewidths and amplitudes we can form any relevant experimental spectrum using a least square fit. This is illustrated for Gaussian and Lorentzian spectra, Voigt profiles and box shapes. Eventually, the procedure is applied to an experimental spectrum of a quantum dot superluminescent diode which determines the first- and second-order temporal correlation functions of the emission. We find good agreement with the experimental data and a quantized treatment. Thus, a superposition of independent stochastic oscillators represents the first- and second-order correlation properties of broadband light emitted by quantum dot superluminescent diodes.
文摘The present study is designed to simulate and study the production of single crystals of semi-organic non-linear optical Glycine Sodium Nitrate (GSN) by using hyper6 software and experimentally by slow evaporation technique. This work has investigated the molecular properties of the crystals using the density functional theory to obtain the infrared spectrum of the crystal by simulation. The FTIR investigation of growing crystal has shown that the spectrum of the GSN crystal compared to simulation evaluation is similar;the only difference is in the range of 1.9% to 2.75% of wavelength peak values. The ultraviolet experimental measurement of the GSN molecule reveals the possibility of non-linear properties due to the spectrum cutoff in the wavelength peak of 301 nm. There was a significantly positive correlation between simulation and experimental assessment.
文摘<div style="text-align:justify;"> This study demonstrates mathematical analysis of biodegradation processes of xenobiotic polymers. A model for microbial population is based on the fact that growth rate of microorganisms is proportional to the microbial population and consumption rate of parts of carbon sources. The model is paired with a model for weight distribution. Those models lead to inverse problems for a molecular factor and a time factor of degradation rate. Solution of the inverse problems allows us to simulate the biodegra-dation process. </div>
文摘The stability of underground excavations has become an important issue in order to extend underground mining operations and extract deeper deposits. The increasing demand for Tin-Tungsten (Sn-W) for industry and its market price has created a motivation for mining companies to extract deep-seated Sn-W ore deposits in Myanmar. Thus, this paper aims to investigate the stability of underground openings, especially, the stope with considering the mining methods. To meet the objective, FLAC<sup>3D</sup> 5.0 simulation was used for the assessment of stope under different stress ratios, 0.5, 1.0, and 1.5 for two types of underground mines;Open stoping and Cut and Fill stoping. The results show that the risk of instability of stope is high under the stress ratio of <em>K</em> = 0.5 than that of <em>K</em> = 1.0 and <em>K</em> = 1.5 in both mining methods. However, the stability of the stope in open stope method is lower than that of cut-and-fill method obviously. This result shows that the appropriate mining method has to be selected for extraction of Sn-W deposit carefully in terms of the balance of safety and cost.
基金This work was supported by the National Science and Technology Major Project of China(No.2018ZX03002002)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(No.61521003).
文摘In recent years,an increasing number of application services are deployed in the cloud.However,the cloud platform faces unknown security threats brought by its unknown vulnerabilities and backdoors.Many researchers have studied the Cyber Mimic Defense(CMD)technologies of the cloud services.However,there is a shortage of tools that enable researchers to evaluate their newly proposed cloud service CMD mechanisms,such as scheduling and decision mechanisms.To fill this gap,we propose MimicCloudSim as a mimic cloud service simulation system based on the basic functionalities of CloudSim.MimicCloudSim supports the simulation of dynamic heterogeneous redundancy(DHR)structure which is the core architecture of CMD technology,and provides an extensible interface to help researchers implement new scheduling and decision mechanisms.In this paper,we firstly describes the architecture and implementation of MimicCloudSim,and then discusses the simulation process.Finally,we demonstrate the capabilities of MimicCloudSim by using a decision mechanism.In addition,we tested the performance of MimicCloudSim,the conclusion shows that MimicCloudSim is highly scalable.
文摘利用Deform-3D软件对AISI4340钢Ф600 mm铸坯至300 mm x 300 mm坯的开坯过程工艺参数进行了数值模拟。通过对加热温度、轧制速度、压下率、2道次压下对铸坯心部变形和材料流动影响的研究,分析了开坯成形过程中心部等效应力和材料变形特点,获得了Ф600圆连铸坯开坯成300mm方坯的成形规律。结果表明:在1070-1140℃内,加热温度对心部的应变影响较小,变化幅度在2.3%左右。当轧制速度选1.0~2.0 m/s、总压.下量一定的情况下,先大后小更利于心部缺陷的焊合。