Aiming at the time redundancy in the fiat panel display （FPD） imaging process, the paper studied some problems for FPD gray scale controlling based on the fraetal theory, dissertates the construction of the space-ti...Aiming at the time redundancy in the fiat panel display （FPD） imaging process, the paper studied some problems for FPD gray scale controlling based on the fraetal theory, dissertates the construction of the space-time mapping topology architecture, the proposition of optimal scanning structure for FPD＇s gray imaging, and the creation of the fractal theoretic model. Then the logic implementation and system application are presented based on the fraetal model of the optimal scan architecture, and the application results achieved target of eliminating time redundancy and increasing the scanning availability. The novel control mode that the fractal scanning IP core described with Verilog language embedded in the FPGA hardware frame can efficiently increase the imaging gray scales and quality in the FPDs scanning controller and speed up the frame frequency of display system.展开更多
<span style="font-family:Verdana;">Laser surface hardening is becoming one of the most successful heat treatment processes for improving wear and fatigue properties of steel parts. In this process, the...<span style="font-family:Verdana;">Laser surface hardening is becoming one of the most successful heat treatment processes for improving wear and fatigue properties of steel parts. In this process, the heating system parameters and the material properties have important effects on the achieved hardened surface characteristics. The control of these variables using predictive modeling strategies leads to the desired surface properties without following the fastidious trial and error method. However, when the dimensions of the surface to be treated are larger than the cross section of the laser beam, various laser scanning patterns can be used. Due to their effects on the hardened surface properties, the attributes of the selected scanning patterns become significant variables in the process. This paper presents numerical and experimental investigations of four scanning patterns for laser surface hardening of AISI 4340 steel. The investigations are based on exhaustive modelling and simulation efforts carried out using a 3D finite element thermal analysis and structured experimental study according to Taguchi method. The temperature distribution and the hardness profile attributes are used to evaluate the effects of heating parameters and patterns design parameters on the hardened surface characteristics. This is very useful for integrating the scanning patterns</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">’</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> features in an efficient predictive modeling approach. A structured experimental design combined to improved statistical analysis tools </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">is</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> used</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> to</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> assess the 3D model performance. The experiments are performed on a 3 kW Nd:Yag laser system. The modeling results exhibit a great agreement between the predicted and measured values for the hardened surface characteristics. The model evaluation reveal</span></span></span><span><span><span>s </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">also its ability to provide not only accurate and robust predictions of the temperature distribution and the hardness profile as well an in-depth analysis of the effects of the process parameters.</span></span></span>展开更多
目的描述淄博市发热伴血小板减少综合征(severe fever with thrombocytopenia syndrome,SFTS)的时空分布特征,识别其环境影响因素及潜在高风险区域,为防控SFTS提出针对性的策略。方法收集2010—2024年淄博市SFTS发病数据,采用时空扫描...目的描述淄博市发热伴血小板减少综合征(severe fever with thrombocytopenia syndrome,SFTS)的时空分布特征,识别其环境影响因素及潜在高风险区域,为防控SFTS提出针对性的策略。方法收集2010—2024年淄博市SFTS发病数据,采用时空扫描统计法识别病例聚集的时间和区域,利用最大熵(maximum entropy,MaxEnt)模型分析环境影响因素并预测高风险区域。结果2010—2024年淄博市共报告459例SFTS病例,年发病数逐年上升,每年4~10月为发病高峰。时空扫描统计显示存在1个一类聚集区和1个二类聚集区:一类聚集区位于沂源县全境和博山区南部(2024年4~9月);二类聚集区分别位于淄川区中部(2024年7~9月)。MaxEnt模型表明,年平均大气压(yearly average atmospheric pressure,PRS)、年平均蒸发量(yearly average evaporation,EVP)、日照时间(yearly average sunshine duration,SSD)和山羊密度(goat density,Goat)是影响SFTS发生的关键因素。风险预测图显示,高发区面积为1116 km 2,占全市总面积的18.71%。结论SFTS时空分布具有异质性,受多维环境因素影响。建议以此为基础划分风险区域并制定防控措施。展开更多
基金supported by the Key Laboratory of Advanced Display and System Applications(Shanghai University),Ministry of Education,China(Grant No.P200803)the Science and Technology Commission of Shanghai Municipality(Grant No.09ZR1412000)
文摘Aiming at the time redundancy in the fiat panel display （FPD） imaging process, the paper studied some problems for FPD gray scale controlling based on the fraetal theory, dissertates the construction of the space-time mapping topology architecture, the proposition of optimal scanning structure for FPD＇s gray imaging, and the creation of the fractal theoretic model. Then the logic implementation and system application are presented based on the fraetal model of the optimal scan architecture, and the application results achieved target of eliminating time redundancy and increasing the scanning availability. The novel control mode that the fractal scanning IP core described with Verilog language embedded in the FPGA hardware frame can efficiently increase the imaging gray scales and quality in the FPDs scanning controller and speed up the frame frequency of display system.
文摘<span style="font-family:Verdana;">Laser surface hardening is becoming one of the most successful heat treatment processes for improving wear and fatigue properties of steel parts. In this process, the heating system parameters and the material properties have important effects on the achieved hardened surface characteristics. The control of these variables using predictive modeling strategies leads to the desired surface properties without following the fastidious trial and error method. However, when the dimensions of the surface to be treated are larger than the cross section of the laser beam, various laser scanning patterns can be used. Due to their effects on the hardened surface properties, the attributes of the selected scanning patterns become significant variables in the process. This paper presents numerical and experimental investigations of four scanning patterns for laser surface hardening of AISI 4340 steel. The investigations are based on exhaustive modelling and simulation efforts carried out using a 3D finite element thermal analysis and structured experimental study according to Taguchi method. The temperature distribution and the hardness profile attributes are used to evaluate the effects of heating parameters and patterns design parameters on the hardened surface characteristics. This is very useful for integrating the scanning patterns</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">’</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> features in an efficient predictive modeling approach. A structured experimental design combined to improved statistical analysis tools </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">is</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> used</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> to</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> assess the 3D model performance. The experiments are performed on a 3 kW Nd:Yag laser system. The modeling results exhibit a great agreement between the predicted and measured values for the hardened surface characteristics. The model evaluation reveal</span></span></span><span><span><span>s </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">also its ability to provide not only accurate and robust predictions of the temperature distribution and the hardness profile as well an in-depth analysis of the effects of the process parameters.</span></span></span>
文摘目的描述淄博市发热伴血小板减少综合征(severe fever with thrombocytopenia syndrome,SFTS)的时空分布特征,识别其环境影响因素及潜在高风险区域,为防控SFTS提出针对性的策略。方法收集2010—2024年淄博市SFTS发病数据,采用时空扫描统计法识别病例聚集的时间和区域,利用最大熵(maximum entropy,MaxEnt)模型分析环境影响因素并预测高风险区域。结果2010—2024年淄博市共报告459例SFTS病例,年发病数逐年上升,每年4~10月为发病高峰。时空扫描统计显示存在1个一类聚集区和1个二类聚集区:一类聚集区位于沂源县全境和博山区南部(2024年4~9月);二类聚集区分别位于淄川区中部(2024年7~9月)。MaxEnt模型表明,年平均大气压(yearly average atmospheric pressure,PRS)、年平均蒸发量(yearly average evaporation,EVP)、日照时间(yearly average sunshine duration,SSD)和山羊密度(goat density,Goat)是影响SFTS发生的关键因素。风险预测图显示,高发区面积为1116 km 2,占全市总面积的18.71%。结论SFTS时空分布具有异质性,受多维环境因素影响。建议以此为基础划分风险区域并制定防控措施。
