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Direction-Dependent Switching in Nonlinear Chirped Gratings

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Chinese Physics Letters 1996年第4期13卷 285-288页

作者： LIU jun-min LIAO Chang-jun LIU Song-hao XU Wen-cheng Institute of Quantum Electronics South China Normal UniversityGuangzhou 510631

Chirped gratings with uniform Kerr nonlinearity are numerically demons traced to have direction-dependent switching behavior,which is caused by the different energy storage between the two incident *** effect can iind... 详细信息

关键词： Chirped optical Switching

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中国7个大区女性肤色测定和分级研究

日用化学品科学 2024年第5期47卷 48-55,76页

作者：徐旻俊傅思颖徐振上海橘宜化妆品有限公司上海201102 厦门美图宜肤科技有限公司福建厦门361100

为了探索中国女性肤色分布情况,利用同一型号的皮肤影像分析系统测量东北、华北、华东、华南、华中、西北和西南7个大区共10200名受试者的面部皮肤颜色。分析了这些样本在CIELAB色彩空间中的分布情况。并分析了多个色彩指标(L^(*)a^(*)b... 详细信息

为了探索中国女性肤色分布情况,利用同一型号的皮肤影像分析系统测量东北、华北、华东、华南、华中、西北和西南7个大区共10200名受试者的面部皮肤颜色。分析了这些样本在CIELAB色彩空间中的分布情况。并分析了多个色彩指标(L^(*)a^(*)b^(*)、ITA°、Hue、RGB、HSV)之间的相关性,最后选取了相关性较低的ITA°和Hue来绘制一个二维平面用于展示该7个大区样本的聚类结果。采用了潘通肤色指南对该7个大区的样本进行了归类。最后通过改进kmeans算法在肤色聚类中的应用将样本分为9类,并对样本进行了归类。结果表明,全国整体分布方面,本次采样中没有观察到皮肤颜色分级(skin color categories)的Ⅵ型的样本,大部分样本属于Ⅲ型和Ⅱ型;在剔除样本数少于100(总样本量的1%)的色号后,仅观察到潘通肤色指南12个色号,其中4Y07的样本最多;聚类划分中,聚类分类4观察到的样本最多,聚类分类8样本最少。区域分布方面,从ITA°和Hue的分布来看:东北肤色最浅最黄,西南大区肤色最红;潘通肤色指南显示,西南肤色色调最偏红(红调占比10.78%),华南皮肤色调最偏黄(红调占比5.73%);聚类划分显示,各大区聚类分类4的人数均是最多的;聚类分类8均是最少的。在各大区内部,各聚类分类占比最高的分别是东北(聚类分类0)、西南(聚类分类1)、华中(聚类分类2)、华北(聚类分类3)、华南(聚类分类4、6、7、8)和西北(聚类分类5)。

关键词：皮肤颜色个体类型角中国人群潘通肤色指南聚类算法

Projective Synchronization of Complex Dynamical Networks with Time-Varying Coupling Strength via Hybrid Feedback Control

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Chinese Physics Letters 2011年第12期28卷 51-54页

作者： GUO Xiao-Yong LI jun-min Department of Applied Mathematics Xidian UniversityXi'an 710071 Department of Mathematics and Science Lincang Normal CollegeLincang 677000

We introduce a hybrid feedback control scheme to design a controller for the projective synchronization of complex dynamical networks with unknown periodically time-varying parameters.A differential-difference mixed parametric learning law and an adaptive learning control law are constructed to ensure the asymptotic convergence of the error in the sense of square error ***,numerical simulation results are used to verify the effectiveness of the proposed method.

关键词： method error asymptotic

Adaptive Iterative Learning Control for Nonlinear Time-delay Systems with Periodic Disturbances Using FSE-neural Network

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International Journal of Automation and computing 2011年第4期8卷 403-410页

作者： Chun-Li Zhang jun-min Li Department of Applied Mathematics Xidian University Xi＇an 710071 PRC

An adaptive iterative learning control scheme is presented for a class of strict-feedback nonlinear time-delay systems, with unknown nonlinearly parameterised and time-varying disturbed functions of known periods. Radial basis function neural network and Fourier series expansion （FSE） are combined into a new function approximator to model each suitable disturbed function in systems. The requirement of the traditional iterative learning control algorithm on the nonlinear functions （such as global Lipschitz condition） is relaxed. Furthermore, by using appropriate Lyapunov-Krasovskii functionals, all signs in the closed loop system are guaranteed to be semiglobally uniformly ultimately bounded, and the output of the system is proved to converge to the desired trajectory. A simulation example is provided to illustrate the effectiveness of the control scheme.

关键词： Adaptive control iterative learning control (ILC) time-delay systems Fourier series expansion-neural network periodic disturbances.

Hybrid Function Projective Synchronization of Chaotic Systems with Uncertain Time-varying Parameters via Fourier Series Expansion

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International Journal of Automation and computing 2012年第4期9卷 388-394页

作者： Zhang, Chun-Li Li, jun-min Department of Applied Mathematics Xidian University Xi'an 710071 China

In this paper, the hybrid function projective synchronization (HFPS) of different chaotic systems with uncertain periodically time-varying parameters is carried out by Fourier series expansion and adaptive bounding technique. Fourier series expansion is used to deal with uncertain periodically time-varying parameters. Adaptive bounding technique is used to compensate the bound of truncation errors. Using the Lyapunov stability theory, an adaptive control law and six parameter updating laws are constructed to make the states of two different chaotic systems asymptotically synchronized. The control strategy does not need to know the parameters thoroughly if the time-varying parameters are periodical functions. Finally, in order to verify the effectiveness of the proposed scheme, the HFPS between Lorenz system and Chen system is completed successfully by using this scheme.

关键词： Hybrid function projective synchronization (HFPS) chaotic systems adaptive control Fourier series expansion Lyapunov stability.

GH_2 Control for Uncertain Discrete-time-delay Fuzzy Systems Based on a Switching Fuzzy Model and Piecewise Lyapunov Function

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International Journal of Automation and computing 2009年第3期6卷 261-266页

作者： Zhi-Le Xia jun-min Li School of Science Xidian University Xi＇an 710071 PRC School of Mathematics and Information Engineering Taizhou University Taizhou 317000 PRC

Generalized H2 （GH2） stability analysis and controller design of the uncertain discrete-time Takagi-Sugeno （T-S） fuzzy systems with state delay are studied based on a switching fuzzy model and piecewise Lyapunov function. GH2 stability sufficient conditions are derived in terms of linear matrix inequalities （LMIs）. The interactions among the fuzzy subsystems are considered. Therefore, the proposed conditions are less conservative than the previous results. Since only a set of LMIs is involved, the controller design is quite simple and numerically tractable. To illustrate the validity of the proposed method, a design example is provided.

关键词： Generalized H2 (GH2) control fuzzy systems linear matrix inequalities (LMIs) piecewise Lyapunov function switchingfuzzy model.

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睡眠剥夺诱导骨代谢紊乱及运动调控机制研究

中华骨质疏松和骨矿盐疾病杂志 2024年第3期17卷 286-294页

作者：徐帅王飞薛香莉雷森林汪君民谌晓安吉首大学体育科学学院湖南吉首416000 淮阴师范学院体育学院江苏淮安223300 聊城市第三人民医院康复医学科山东聊城252000 山东大学体育学院济南250061

睡眠通过促进身体恢复、修复和生长,在改善身心健康方面发挥重要作用。其中睡眠剥夺(sleep deprivation,SD)被认为是一种公共卫生流行病,已有研究证实SD破坏骨微结构,造成新骨形成过程受到抑制,最终对骨骼代谢和骨平衡造成不良的影响。... 详细信息

睡眠通过促进身体恢复、修复和生长,在改善身心健康方面发挥重要作用。其中睡眠剥夺(sleep deprivation,SD)被认为是一种公共卫生流行病,已有研究证实SD破坏骨微结构,造成新骨形成过程受到抑制,最终对骨骼代谢和骨平衡造成不良的影响。运动作为非医疗干预手段,与骨骼稳态有密切相关性,运动的应力性作用会有效提高骨骼质量。运动能够有效缓解SD的恶性发展,进而减轻SD对骨代谢造成的损害。本文将对SD与骨骼质量相关研究进行综述,并论述运动改善睡眠的调控作用,以期为维护骨健康提供新的思路和研究视角。

关键词：睡眠剥夺骨代谢运动调控骨密度

Cross-correlation of 21 cm and soft X-ray backgrounds during the epoch of reionization

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Research in Astronomy and Astrophysics 2016年第8期16卷 135-144页

作者： jun-min Liang Xiao-Chun Mao Bo Qin National Astronomical Observatories Chinese Academy of Sciences

The cross-correlation between the high-redshift 21 cm background and the Soft X-ray Background （SXB） of the Universe may provide an additional probe of the Epoch of Reionization. Here we use semi-numerical simulations to create 21 cm and soft X-ray intensity maps and construct their cross power spectra. Our results indicate that the cross power spectra are sensitive to the thermal and ionizing states of the intergalactic medium （IGM）. The 21 cm background correlates positively to the SXB on large scales during the early stages of the reionization. However as the reionization develops, these two back- grounds turn out to be anti-correlated with each other when more than - 15% of the IGM is ionized in a warm reionization scenario. The anti-correlated power reaches its maximum when the neutral fraction declines to 0.2-0.5. Hence, the trough in the cross power spectrum might be a useful tool for tracing the growth of HII regions during the middle and late stages of the reionization. We estimate the detectability of the cross power spectrum based on the abilities of the Square Kilometre Array and the Wide Field X-ray Telescope （WFXT）, and find that to detect the cross power spectrum, the pixel noise of X-ray images has to be at least 4 orders of magnitude lower than that of the WFXT deep survey.

关键词： cosmic background radiation -- cosmology: theory -- dark ages reionization first stars --early Universe -- diffuse radiation -- X-rays: diffuse background

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松三糖对溃疡性结肠炎的作用

中国临床药理学杂志 2024年第14期40卷 2083-2087页

作者：陈章浩高霜李进发干振常军民新疆医科大学药学院新疆维吾尔自治区乌鲁木齐830011 新疆天然药物活性组分与释药技术重点实验室新疆维吾尔自治区乌鲁木齐830000

目的通过葡聚糖硫酸钠(DSS)诱导建立溃疡性结肠炎(UC)小鼠模型,探讨松三糖(MELE)对UC小鼠的作用机制。方法将48只SPF级雄性c57BL/6小鼠随机分为正常组(0.9%NaCl)、模型组(0.9%NaCl)、对照组(100 mg·kg^(-1)美拉沙秦)和低、中、高剂量... 详细信息

目的通过葡聚糖硫酸钠(DSS)诱导建立溃疡性结肠炎(UC)小鼠模型,探讨松三糖(MELE)对UC小鼠的作用机制。方法将48只SPF级雄性c57BL/6小鼠随机分为正常组(0.9%NaCl)、模型组(0.9%NaCl)、对照组(100 mg·kg^(-1)美拉沙秦)和低、中、高剂量实验组(20、40、80 mg·kg^(-1)松三糖溶液)。通过给予3%DSS溶液代替饮用水诱导UC模型,并进行疾病活动指数(DAI)评估。用酶联免疫吸附试验法检测血清中白细胞介素-1β(IL-1β)、IL-6、IL-10和肿瘤坏死因子-α(TNF-α)水平,用蛋白质印迹法检测主要组织相容性复合体Ⅱ(MHCⅡ)和表面抗原分化簇4受体(CD4)蛋白的表达水平。结果中、高剂量实验组和模型组、正常组的血清中IL-1β水平分别为(82.15±13.66)、(75.56±11.07)、(118.20±19.31)和(23.47±4.72)pg·mL^(-1),IL-6水平分别为(71.54±16.48)、(58.57±15.62)、(140.60±5.76)和(30.33±4.15)pg·mL^(-1),IL-10水平分别为(48.64±5.60)、(52.65±7.99)、(27.10±4.91)和(61.90±10.44)pg·mL^(-1),TNF-α水平分别为(70.33±8.51)、(66.55±8.12)、(90.88±4.90)和(34.18±4.15)pg·mL^(-1),MHCⅡ蛋白相对表达水平分别为0.34±0.04、0.15±0.06、0.08±0.05和0.53±0.59,CD4蛋白相对表达水平分别为0.79±0.08、0.92±0.12、0.99±0.11和0.54±0.14。中、高剂量实验组和正常组的上述指标与模型组比较,在统计学上差异均有统计学意义(P<0.05,P<0.01)。结论松三糖能够有效改善UC小鼠的症状,其作用机制可能是通过下调MHCⅡ蛋白和上调CD4蛋白表达来激活T细胞信号通路,从而发挥抗炎作用。

关键词：刺糖松三糖溃疡性结肠炎抗炎