To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,a...To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB.展开更多
基于MCNP程序模拟计算了不同孔隙度二氧化硅介质地层14 Me V中子慢化长度与中子迁移长度。首先,模拟计算了241Am-Be中子源条件下不同孔隙度Si O2介质地层的中子通量空间分布,并利用源距均方值公式计算得到了对应的中子慢化长度LS和中子...基于MCNP程序模拟计算了不同孔隙度二氧化硅介质地层14 Me V中子慢化长度与中子迁移长度。首先,模拟计算了241Am-Be中子源条件下不同孔隙度Si O2介质地层的中子通量空间分布,并利用源距均方值公式计算得到了对应的中子慢化长度LS和中子迁移长度LM。与文献结果对比:中子特征长度LS与LM结果相对误差均值分别为1.20%与-2.60%;该结果验证了源距均方值公式计算中子特征长度的有效性和可行性。同样地,计算得到了不同孔隙度Si O2介质地层14 Me V中子的中子特征长度LS和LM;计算结果表明:14 Me V中子的中子特征长度同样随地层孔隙度的增加而降低;其中水的14Me V中子特征长度为LS=12.73 cm、LM=13.00 cm,Si O2的14 Me V中子特征长度为LS=30.08 cm、LM=34.31 cm;中子慢化长度LS结果与文献结果的相对偏差≤±3.1%。展开更多
The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimizatio...The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimization criterion and the EE of D2D multicast groups are taken as the optimization objective function.The aim is to maximize the minimum EE for different D2D multicast groups under the constraints of the maximum transmit power and minimum transmit rate,which is modeled as a non-convex and mixed-integer fractional programming problem.Here,suboptimal resource allocation algorithms are proposed to solve this problem.First,channel assignment scheme is performed to assign channel to D2D multicast groups.Second,for a given channel assignment,iterative power allocation schemes with and without loss of cellular users’rate are completed,respectively.Simulation results corroborate the convergence performance of the proposed algorithms.In addition,compared with the traditional throughput maximization algorithm,the proposed algorithms can improve the energy efficiency of the system and the fairness achieved among different multicast groups.展开更多
文摘To investigate the applicability of four commonly used color difference formulas(CIELAB,CIE94,CMC(1:1),and CIEDE2000)in the printing field on 3D objects,as well as the impact of four standard light sources(D65,D50,A,and TL84)on 3D color difference evaluations,50 glossy spheres with a diameter of 2cm based on the Sailner J4003D color printing device were created.These spheres were centered around the five recommended colors(gray,red,yellow,green,and blue)by CIE.Color difference was calculated according to the four formulas,and 111 pairs of experimental samples meeting the CIELAB gray scale color difference requirements(1.0-14.0)were selected.Ten observers,aged between 22 and 27 with normal color vision,were participated in this study,using the gray scale method from psychophysical experiments to conduct color difference evaluations under the four light sources,with repeated experiments for each observer.The results indicated that the overall effect of the D65 light source on 3D objects color difference was minimal.In contrast,D50 and A light sources had a significant impact within the small color difference range,while the TL84 light source influenced both large and small color difference considerably.Among the four color difference formulas,CIEDE2000 demonstrated the best predictive performance for color difference in 3D objects,followed by CMC(1:1),CIE94,and CIELAB.
文摘基于MCNP程序模拟计算了不同孔隙度二氧化硅介质地层14 Me V中子慢化长度与中子迁移长度。首先,模拟计算了241Am-Be中子源条件下不同孔隙度Si O2介质地层的中子通量空间分布,并利用源距均方值公式计算得到了对应的中子慢化长度LS和中子迁移长度LM。与文献结果对比:中子特征长度LS与LM结果相对误差均值分别为1.20%与-2.60%;该结果验证了源距均方值公式计算中子特征长度的有效性和可行性。同样地,计算得到了不同孔隙度Si O2介质地层14 Me V中子的中子特征长度LS和LM;计算结果表明:14 Me V中子的中子特征长度同样随地层孔隙度的增加而降低;其中水的14Me V中子特征长度为LS=12.73 cm、LM=13.00 cm,Si O2的14 Me V中子特征长度为LS=30.08 cm、LM=34.31 cm;中子慢化长度LS结果与文献结果的相对偏差≤±3.1%。
基金Projects(61801237,61701255)supported by the National Natural Science Foundation of ChinaProject(SBH17024)supported by the Postdoctoral Science Foundation of Jiangsu Province,China+2 种基金Project(15KJB510026)supported by the Natural Science Foundation of the Jiangsu Higher Education Institutions,ChinaProject(BK20150866)supported by the Natural Science Foundation of Jiangsu Province,ChinaProjects(NY215046,NY217056)supported by the Introduction of Talent Fund of Nanjing University of Posts and Telecommunications,China
文摘The resource allocation for device-to-device(D2D)multicast communications is investigated.To achieve fair energy efficiency(EE)among different multicast groups,the max-min fairness criterion is used as the optimization criterion and the EE of D2D multicast groups are taken as the optimization objective function.The aim is to maximize the minimum EE for different D2D multicast groups under the constraints of the maximum transmit power and minimum transmit rate,which is modeled as a non-convex and mixed-integer fractional programming problem.Here,suboptimal resource allocation algorithms are proposed to solve this problem.First,channel assignment scheme is performed to assign channel to D2D multicast groups.Second,for a given channel assignment,iterative power allocation schemes with and without loss of cellular users’rate are completed,respectively.Simulation results corroborate the convergence performance of the proposed algorithms.In addition,compared with the traditional throughput maximization algorithm,the proposed algorithms can improve the energy efficiency of the system and the fairness achieved among different multicast groups.
