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A Novel Improved Puma Optimizer to Boost Photovoltaic Array Production in Partially Shaded Environments
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作者 Nagwan Abdel Samee Ahmed Fathy +2 位作者 Mohamed A.Mahdy Maali Alabdulhafith Essam H.Houssein 《Computer Modeling in Engineering & Sciences》 2026年第2期737-771,共35页
This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raph... This research proposes an improved Puma optimization algorithm(IPuma)as a novel dynamic recon-figuration tool for a photovoltaic(PV)array linked in total-cross-tied(TCT).The proposed algorithm utilizes the Newton-Raphson search rule(NRSR)to boost the exploration process,especially in search spaces with more local regions,and boost the exploitation with adaptive parameters alternating with random parameters in the original Puma.The effectiveness of the introduced IPuma is confirmed through comprehensive evaluations on the CEC’20 benchmark problems.It shows superior performance compared to both established and modern metaheuristic algorithms in terms of effectively navigating the search space and achieving convergence towards near-optimal regions.The findings indicated that the IPuma algorithm demonstrates considerable statistical promise and surpasses the performance of competing algorithms.In addition,the proposed IPuma is utilized to reconfigure a 9×9 PV array that operates under different shade patterns,such as lower triangular(LT),long wide(LW),and short wide(SW).In addition to other programmed approaches,such as the Whale optimization algorithm(WOA),grey wolf optimizer(GWO),Harris Hawks optimization(HHO),particle swarm optimization(PSO),gravitational search algorithm(GSA),biogeography-based optimization(BBO),sine cosine algorithm(SCA),equilibrium optimizer(EO),and original Puma,the indicated method is contrasted to the traditional configurations of TCT and Sudoku.In addition,the metrics of mismatch power loss,maximum efficiency improvement,efficiency improvement ratio,and peak-to-mean ratio are calculated to assess the effectiveness of the indicated approach.The proposed IPuma improved the generated power by 36.72%,28.03%,and 40.97%for SW,LW,and LT,respectively,outperforming the TCT configuration.In addition,it achieved the best maximum efficiency improvement among the algorithms considered,with 26.86%,21.89%,and 29.07%for the examined patterns.The results highlight the superiority and competence of the proposed approach in both convergence rates and stability,as well as applicability to dynamically reconfigure the PV system and enhance its harvested energy. 展开更多
关键词 Photovoltaic partial shade RECONFIGURATION improved puma METAHEURISTIC
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Development of a First Prototype of a Liquid-Shaded Dynamic Glazed Facade for Buildings
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作者 Marco Cecchi 《Journal of Civil Engineering and Architecture》 2025年第6期296-304,共9页
This paper will report on the development of a prototype of actively controlled facade module,which is capable of adapting its solar transmittance to changeable solar gains.Hence this new facade offers additional feat... This paper will report on the development of a prototype of actively controlled facade module,which is capable of adapting its solar transmittance to changeable solar gains.Hence this new facade offers additional features with respect to the most popular currently used glass facades,which have fixed solar transmittance indeed.The novel technology is made possible by the creation of an additional 1.5-mm-thick sliding shielding liquid,which flows internally,in order to dynamically adapt the window’s solar transmittance.As compared with competitive technologies,this shielding system has low manufacturing costs,is durable,is completely reversible and always transparent,irrespective of its transmittance state.Specifically,the manufacture of a full-size window prototype and the engineering of the window was carried out;moreover,glass pane bending when subject to hydrostatic pressure was eventually assessed.All this information has been used to set up the industrial process needed for its manufacturing. 展开更多
关键词 Active solar control liquid shading window smart buildings
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Performance assessment of meta-heuristic MPPT strategies for solar panels under complex partial shading conditions and load variation
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作者 Abdulbari Talib Naser Nur Fadilah Ab Aziz +2 位作者 Karam Khairullah Mohammed Karmila binti Kamil Saad Mekhilef 《Global Energy Interconnection》 2025年第4期554-571,共18页
Weather variations present a major challenge for photovoltaic(PV)systems in obtaining the optimal output during maximum power point tracking(MPPT),particularly under partial shadowing conditions(PSCs).Bypass diodes ar... Weather variations present a major challenge for photovoltaic(PV)systems in obtaining the optimal output during maximum power point tracking(MPPT),particularly under partial shadowing conditions(PSCs).Bypass diodes are typically installed across the series-connected PV modules to avoid the occurrence of the hotspots.Consequently,the power curve exhibits several local peaks(LPs)and one global peak(GP).The conventional MPPTs typically become stuck in one of these LPs,presenting a significant decrease in both the power output and overall efficiency of the PV system.A major constraint of several optimization techniques is their inability to differ-entiate between the irradiancefluctuations and load alterations.In this study,we analyze seven different methods for MPPT.These include:the team game algorithm(TGA),social ki driver algorithm(SSD),differential evolution(DE),grey wolf optimization(GWO),particle swarm optimization(PSO),cuckoo search(CS),and the perturb and observe(P&O)method.These algorithms were applied in practice,and their effectiveness was experimentally demonstrated under different amounts of solar irradiation while maintain-ing a constant temperature.The results indicate that the CS and TGA approaches can accurately track the MPPT across various posi-tions on the P-V curve.These methods achieve average efficiencies of 99.59%and 99.54%,respectively.Additionally,the TGA achieves superior performance with the shortest average tracking time of 0.92 s,outperforming the existing MPPT algorithms. 展开更多
关键词 Maximum power point tracking(MPPT) Partial shading conditions(PSCs) Photovoltaic system(PV) Particle swarm optimization(PSO)
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基于改进L-SHADE算法的UAV集群火力分配
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作者 王立伟 寇有财 白帆 《信息化研究》 2025年第6期195-201,共7页
无人机(UAV)集群的火力分配是提升其作战能力的关键之一。为充分发挥UAV集群作战优势,既可完成打击任务要求,又能消耗较少成本,建立了包含目标毁伤要求、武器消耗约束的火力分配数学模型,改进了基于线性种群规模缩减和成功历史的参数自... 无人机(UAV)集群的火力分配是提升其作战能力的关键之一。为充分发挥UAV集群作战优势,既可完成打击任务要求,又能消耗较少成本,建立了包含目标毁伤要求、武器消耗约束的火力分配数学模型,改进了基于线性种群规模缩减和成功历史的参数自适应差分进化(L-SHADE)算法进行求解。通过引入种群参数自适应调整、个体适应度评分选择、非线性种群规模缩减等策略,提高算法的全局探索与局部开发能力。为提高寻优效率,提出了一种压缩决策变量上界约束的方法,可有效缩小问题求解空间。仿真试验表明,所提方法可有效求解UAV集群火力分配问题。 展开更多
关键词 无人机 火力分配 L-SHADE 参数自适应 种群缩减 压缩上界
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基于IPSO-NTSMC的光伏MPPT控制方法
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作者 常雨芳 罗梦瑶 +2 位作者 高鹏 严怀成 黄文聪 《太阳能学报》 北大核心 2026年第1期82-88,共7页
针对局部阴影下光伏阵列输出功率的多峰值问题,提出一种将改进粒子群算法和非奇异终端滑模控制融合的复合控制方法。首先,分析光伏阵列的数学模型及输出特性;其次,设计改进粒子群算法,减小惯性权重在算法执行过程中的影响,提高局部阴影... 针对局部阴影下光伏阵列输出功率的多峰值问题,提出一种将改进粒子群算法和非奇异终端滑模控制融合的复合控制方法。首先,分析光伏阵列的数学模型及输出特性;其次,设计改进粒子群算法,减小惯性权重在算法执行过程中的影响,提高局部阴影下光伏系统的输出功率;再次,设计非奇异终端滑模切换面,以克服传统滑模的奇异问题,简化系统结构并提高稳态精度;最后,通过Matlab/Simulink平台开展仿真实验,并与现有方法进行对比,结果表明所提策略在跟踪速度、稳态功率波动等方面均表现出更优性能,可显著改善光伏系统的最大功率点跟踪效果。 展开更多
关键词 光伏阵列 太阳电池 滑模控制 最大功率点跟踪 粒子群优化算法
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探究客观评级法在色牢度深浅色判定中的应用
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作者 唐颖 《合成纤维》 2026年第3期40-44,共5页
探究了基于Berns公式的客观评级法在深浅色判定中的应用。通过Datacolor 600测色仪对187个Pantone色卡样本进行色度学参数测量,结合CIELAB色度空间,提出以颜色深度值为核心判定指标,并引入色空间距离法优化色相划分。试验表明,客观评级... 探究了基于Berns公式的客观评级法在深浅色判定中的应用。通过Datacolor 600测色仪对187个Pantone色卡样本进行色度学参数测量,结合CIELAB色度空间,提出以颜色深度值为核心判定指标,并引入色空间距离法优化色相划分。试验表明,客观评级法的准确率达97.9%,显著优于传统主观评级及单一明度值(L^(*))判定法(92.51%)。研究验证了客观评级法在提高判定稳定性与准确性方面的有效性,为纺织品色牢度标准化测试提供了可靠的技术支持。 展开更多
关键词 深浅色判定 客观评级法 色空间距离法
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Photoinhibition in Shaded Cotton Leaves After Exposing to High Light and the Time Course of Its Restoration 被引量:27
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作者 杨兴洪 邹琦 王玮 《Acta Botanica Sinica》 CSCD 2001年第12期1255-1259,共5页
Chlorophyll fluorescence emission, pigment composition and photosynthetic rate of shade-grown cotton ( Gossypium hirsutum L.) plants were measured immediately after suddenly exposing to full sunlight and at regular in... Chlorophyll fluorescence emission, pigment composition and photosynthetic rate of shade-grown cotton ( Gossypium hirsutum L.) plants were measured immediately after suddenly exposing to full sunlight and at regular intervals there after within 15 d. Photoinhibition occurred in shade-grown cotton leaves immediately after exposed to full sunlight. The chlorophyll fluorescence parameter F-v/F-m and PhiPS II, which reflect the efficiency of PS II,obviously decreased in shade-grown leaves, much lower than that of the full sunlight-grown leaves. On the contrary, F-o value was sharply increased. Neither of these parameters could completely recover till next morning. The photoinhibition was chronic and continued for about 4 d, while the F-v/F-m and the net photosynthetic rate ( P-n) continued to decline, then began to increase gradually 6 d later and turned stable after 10 - 12 d, appearing as an acclimation phenomenon. However, the final value of F-v/F-m and P-n did not reach the level as in those leaves grown in the full sunlight ever before. The final P-n was higher by 60% than that before exposure, but lower for more than 40% than that of the full sunlight-grown leaves. The most notable response of chloroplast pigment composition was a pronounced increase in the pool size of carotenoids in xanthophyll cycle over a period of 3 d. The results indicated that when shade-grown cotton seedlings were suddenly transferred to the full sunlight, the decline of F-v/F-m and P-n might associate with the damage of the PS II reaction center. During the light acclimation, photoprotective mechanisms such as the xanthophyll cycle-dependent energy dissipation were increased, so that photodamage in leaves transferred from low to high light might be reduced. 展开更多
关键词 Gosstypium hirsutum shading PHOTOINHIBITION PHOTOPROTECTION xanthophyll cycle
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基于Shape-from-Shading的月球表面三维形状恢复算法研究 被引量:2
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作者 杨磊 韩九强 王国珲 《宇航学报》 EI CAS CSCD 北大核心 2008年第6期1995-2000,共6页
提出了一种基于Shape-from-Shading的月球表面三维形状恢复算法。首先分析了在太阳光照射下月球表面成像模型,建立了使用Lommel-Seeliger反射模型描述的反射图方程。然后用有限差分近似微分运算,将反射图方程所示的一阶变系数线性偏微... 提出了一种基于Shape-from-Shading的月球表面三维形状恢复算法。首先分析了在太阳光照射下月球表面成像模型,建立了使用Lommel-Seeliger反射模型描述的反射图方程。然后用有限差分近似微分运算,将反射图方程所示的一阶变系数线性偏微分方程进行离散化处理,得到关于表面高度函数的代数方程。进而采用超松弛迭代法进行求解,获得月球表面三维高度函数值。最后使用合成图像和实际月球图像进行三维形状恢复仿真实验。实验结果表明提出的算法可以有效地恢复月球表面三维形状。 展开更多
关键词 月球表面 三维形状恢复 Shape-from—shading Lommel—Seeliger反射模型 有限差分
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Physiological Basis of Photosynthetic Tolerance to Photooxidation and Shading in Rice 被引量:13
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作者 李霞 焦德茂 《Acta Botanica Sinica》 CSCD 2000年第12期1271-1277,共7页
Thirty genotypes from rice germplasm were identified under photooxidation and shading condition and divided into four basic types : (1) cultivars tolerant to both photooxidation and shading, (2) cultivars tolerant to... Thirty genotypes from rice germplasm were identified under photooxidation and shading condition and divided into four basic types : (1) cultivars tolerant to both photooxidation and shading, (2) cultivars tolerant to photooxidation but sensitive to shading, (3) cultivars tolerant to shading but sensitive to photooxidation, and (4) cultivars sensitive to photooxidation and shading. A comparative study of photosynthetic characteristics of a cultivar (cv. Wuyujing 3) that is tolerant and a cultivar (cv. Xiangxian) that is sensitive to both photoinhibition and shading showed that the photochemical efficiency of PSⅡ ( F v/F m ) and the content of PSⅡ_D1 protein in the tolerant cultivar “Wuyujing 3” decreased less under photoinhibition conditions as compared with “Xiangxian”. Under photooxidation conditions, superoxide dismutase was induced rapidly to a higher level and the active oxygen O - built up to a lower level in “Wuyujing 3” than in “Xiangxian”. At the same time, the photosynthetic rate decreased by 23% in “Wuyujing 3” vs. 64% in “Xiangxian”. Shading (20% natural light) during the booting stage caused only small decreases (7%-13%) in RuBisCO activity and the photosynthetic rate in “Wuyujing 3” but showed marked decreases (57%-64%) in “Xiangxian” which corresponded to the decreases in grain yield in the two cultivars (38% and 73%, respectively). The correlation analysis showed that the tolerance to photooxidation is mainly related to PSⅡ_D1 and that to shading is mainly related to RuBisCO activity. This study provided a simple and effective screening method and physiological basis for crop breeding in enhancing tolerance to both high and low radiation. 展开更多
关键词 PHOTOOXIDATION SHADE RICE PSⅡphotochemical efficiency RuBi0
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X-Rite’s ShadeVision System与Vitapan Classical比色板的匹配性分析 被引量:2
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作者 林芝 刘丽 +2 位作者 朱形好 丁熙 Y Li 《现代口腔医学杂志》 CAS CSCD 北大核心 2007年第5期523-524,共2页
目的X-Rite’sShadeVision System和Vitapan Classical比色板的匹配性。方法采用X-Rite’sShadeVision System对Vitapan Classical比色板进行测色。结果X-Rite’s ShadeVision System测量结果排序与原排序一致,排列差异最大有6个色片的... 目的X-Rite’sShadeVision System和Vitapan Classical比色板的匹配性。方法采用X-Rite’sShadeVision System对Vitapan Classical比色板进行测色。结果X-Rite’s ShadeVision System测量结果排序与原排序一致,排列差异最大有6个色片的差距。相邻比色板的色差ΔEab参差不齐,最大的色差6.92,而最小的色差只有1.21。结论X-Rite’s ShadeVision System与Vitapan Classical比色板不完全匹配。 展开更多
关键词 测色 X-Rite's SHADE Vision System 比色板
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Effects of Shading Treatment on the Growth of Bischofia javanica Seedlings 被引量:2
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作者 於艳萍 毛立彦 +4 位作者 宾振钧 唐春红 王凌晖 时鹏涛 郝小玲 《Agricultural Science & Technology》 CAS 2017年第5期952-956,共5页
With annual Bischofia javanica seedlings as experimental material, the plasticity and comprehensive evaluation methods were employed to investigate the effects of different shading degrees (100% NS (natural sunshine... With annual Bischofia javanica seedlings as experimental material, the plasticity and comprehensive evaluation methods were employed to investigate the effects of different shading degrees (100% NS (natural sunshine), 41.3% NS, 14.6% NS and 3.6% NS) on B. javanica seedlings growth, so as to obtain the shade toler- ance in B. javanica. The results showed that with the shading degree increasing, the seedling height increment, diameter increment, leaf area, fresh weights (above- ground part, underground part and whole plant) and dry weights (aboveground part, underground part and whole plant) of B. javanica seedlings all increased first and then decreased, and reached peak values under 41.3% NS, while the total root length, average root diameter, total surface area, total root volume and total root number all presented a decreasing trend. Also the comprehensive evaluation by subordinate function value method and plasticity analysis were carried out on these growth indexes. It was concluded that B. javanica seedlings have medium shade tol- erance from the comDrehensive analysis of growth indexes. 展开更多
关键词 Bischofia javanica seedlings Shade tolerance GROWTH
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Shadepilot全牙比色仪测定牙龈色对比色板色标颜色的影响 被引量:5
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作者 殷家悦 王飞 +1 位作者 包扬 艾红军 《实用口腔医学杂志》 CAS CSCD 北大核心 2009年第6期791-793,共3页
目的:通过体外模拟实验评价牙龈比色板在临床比色中的意义。方法:使用分光光度计型全牙比色仪Shadepilot测量42个比色板色标在4种牙龈比色板(Gumy1,2,3,4)衬托下颈、中、切3部分色彩参数(CIE1976L*a*b*),使用比色仪内置软件计算有无牙... 目的:通过体外模拟实验评价牙龈比色板在临床比色中的意义。方法:使用分光光度计型全牙比色仪Shadepilot测量42个比色板色标在4种牙龈比色板(Gumy1,2,3,4)衬托下颈、中、切3部分色彩参数(CIE1976L*a*b*),使用比色仪内置软件计算有无牙龈比色板衬托的色标相同位置的色差值(△E),分析牙龈色对色标颜色的影响。结果:42个色标在4种牙龈色衬托下与无牙龈色衬托的色差值为:颈部(2.93±0.79)NBS,中部(0.51±0.27)NBS,切端(0.61±0.29)NBS;Gumy-1、2、3、4组牙龈色对色标颈、中、切三部分的影响组间差异无显著性(P>0.05)。结论:在模拟测量条件下,牙龈色对比色板色标颈部有影响,肉眼可识别,对色标中部及切端无影响;4种模拟牙龈颜色对比色板色标颜色的影响无统计学差异。 展开更多
关键词 牙龈色 比色仪 色差
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Effects of Shading Degree on Storage Rate and Growth of Phoebe bournei Seedlings in Fields 被引量:6
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作者 吴际友 黄明军 +6 位作者 陈明皋 董春英 舒瑶 吴其军 程勇 刘球 王旭军 《Agricultural Science & Technology》 CAS 2014年第9期1567-1570,共4页
In the research, four shading treatments were set, including the treatments with shading degrees at 0, 40%, 60% and 70%, in order to explore storage rate and seedling growth of annual Phoebe bournei. The results showe... In the research, four shading treatments were set, including the treatments with shading degrees at 0, 40%, 60% and 70%, in order to explore storage rate and seedling growth of annual Phoebe bournei. The results showed that the storage rate is growing upon shading degree. In the research, for example, storage rate reached the peak with the shading degree at 70%, and only 42.2% with shading degree at 0. In addition, seedling height and ground diameter showed extremely significant differences among treatments, and the treatment with shading degree at 60% was the best. 展开更多
关键词 Phoebe bournei shading degree Seedling storage rate Seedling height Ground diameter Sowing and seedling cultivation in fields
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基于Shape from Shading的医学图像三维重建 被引量:6
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作者 王瑞胡 《计算机工程与应用》 CSCD 北大核心 2008年第6期222-224,共3页
通过对由医疗成像设备获取的二维灰度图像进行形状重建,得到的三维立体原型能帮助医学诊断人员确诊病情。介绍了Shape from Shading的实现原理和扫描电镜成像系统的简单构成,提出了一种基于线性逼近的用于解决SEM反射映射函数的实现方法... 通过对由医疗成像设备获取的二维灰度图像进行形状重建,得到的三维立体原型能帮助医学诊断人员确诊病情。介绍了Shape from Shading的实现原理和扫描电镜成像系统的简单构成,提出了一种基于线性逼近的用于解决SEM反射映射函数的实现方法,并将之应用于红血细胞的三维图像重构,得到的细胞图形非常接近其真实形状。 展开更多
关键词 SHAPE from shading 扫描电镜 三维重建 红血细胞图像
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作物对间作遮荫胁迫的响应机制及缓解措施研究进展
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作者 刘柱 孟维伟 +7 位作者 林松明 南镇武 张佳蕾 郭峰 谢立勇 于海秋 张正 万书波 《中国油料作物学报》 北大核心 2026年第1期42-53,共12页
作为一种环境友好型种植模式,间作能够增加田间作物多样性和系统生产力,维持农田生态系统稳定性,是发展集约化生态农业的重要措施。然而,由于间作系统中组成作物高度差异,高位作物遮荫使低位作物处于光能劣势,遮荫胁迫成为限制间作系统... 作为一种环境友好型种植模式,间作能够增加田间作物多样性和系统生产力,维持农田生态系统稳定性,是发展集约化生态农业的重要措施。然而,由于间作系统中组成作物高度差异,高位作物遮荫使低位作物处于光能劣势,遮荫胁迫成为限制间作系统产量的主要因素,对作物的植株形态、叶片结构、光合特性和生理特性产生负面影响。因此,本文基于前人研究成果,从作物对遮荫胁迫的响应机制,以及缓解间作遮荫胁迫、改善间作系统光能利用的措施等方面进行综述,以期为耐荫作物品种的选育和间作系统高产稳产提供依据。 展开更多
关键词 间作 遮荫胁迫 光合特性 生理特性 缓解措施
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模拟毛竹扩张对濒危植物华木莲生长及其光合生理特性的影响
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作者 郑崇龙 陈昕 +6 位作者 欧阳园兰 张智华 张振炜 宋庆妮 刘骏 肖智勇 杨清培 《江西农业大学学报》 北大核心 2026年第1期120-130,共11页
【目的】旨在通过模拟毛竹扩张过程中产生的关键环境变化(林下遮阴与土壤养分的改变),探究其对濒危植物华木莲幼苗形态生长、养分吸收以及光合生理特性的影响机制。【方法】基于毛竹扩张会形成高郁闭林冠以及改变土壤养分环境的生态过程... 【目的】旨在通过模拟毛竹扩张过程中产生的关键环境变化(林下遮阴与土壤养分的改变),探究其对濒危植物华木莲幼苗形态生长、养分吸收以及光合生理特性的影响机制。【方法】基于毛竹扩张会形成高郁闭林冠以及改变土壤养分环境的生态过程,试验通过设置不同遮阴和施肥处理进行模拟。共设置7个处理组合:以全光照不施肥(L0N0)模拟毛竹扩张前的原生环境,作为试验的基础对照;全光照施肥(L0N1)、50%遮阴施肥(L1N1)、50%遮阴不施肥(L1N0)、75%遮阴施肥(L2N1)、75%遮阴不施肥(L2N0)用于模拟不同扩张程度下的光照与土壤养分条件的变化;同时,以竹林生境作为现实对照,反映扩张后的实际环境状况,比较分析各处理下华木莲幼苗在生长、光合生理和养分吸收等方面的差异。【结果】(1)遮阴显著抑制华木莲株高与地径生长(P<0.001),而施肥效应不显著(P>0.05),且二者无交互作用,竹林组对生长的抑制作用与75%遮阴组相近。(2)华木莲净光合速率随遮阴的加剧而下降,遮阴会显著降低最大光合速率(P_(max))、暗呼吸速率(Rd)、光饱和点(LSP)和光补偿点(LCP),而施肥仅能提升最大光合速率(P_(max)),且两者对Rd和LCP存在显著交互作用。(3)充足光照有利于提高气孔导度、蒸腾速率和水分利用效率,降低胞间CO_(2)浓度,从而增强光合作用,而遮阴显著抑制了这些光响应参数,导致光合作用和水分利用效率下降。(4)竹林组的N含量与全光照不施肥组差异不显著,但显著低于其他处理(P<0.05),同时竹林组的N∶P最低(11.67)且显著低于其他处理组(P<0.05),这表明在竹林生境下氮素是限制华木莲幼苗更新的关键因素。【结论】毛竹扩张通过光限制和氮素竞争对华木莲幼苗光合作用与生长产生抑制,是加剧其濒危的关键因素,建议对竹林进行疏伐增加林窗透光,同时采取定向补充氮肥等干预措施以保证华木莲的正常更新。 展开更多
关键词 华木莲 濒危植物 遮阴 施肥 光合生理 毛竹扩张
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基于易测林木因子的林下太阳直射辐射模拟
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作者 杜昕 董雪 +2 位作者 谷会岩 李玉博 陈祥伟 《南京林业大学学报(自然科学版)》 北大核心 2026年第1期205-213,共9页
[目的]论证基于易测林木因子模拟林下辐射方法体系中,尺度化加权直射荫蔽度与加权进界邻体直射荫蔽度两种林下直射辐射成分测度指数的模拟准确性,寻求基于简单、易测林木因子较为合理、准确估算林下任意点位直射辐射的模型结构特征。[方... [目的]论证基于易测林木因子模拟林下辐射方法体系中,尺度化加权直射荫蔽度与加权进界邻体直射荫蔽度两种林下直射辐射成分测度指数的模拟准确性,寻求基于简单、易测林木因子较为合理、准确估算林下任意点位直射辐射的模型结构特征。[方法]基于阔叶红松(Pinus koraiensis)林林分调查信息,建立林分体素模型模拟阔叶红松林下直射透射率。将模拟的阔叶红松林下直射透射率作为验证标准,分别以爬山算法对尺度化加权直射荫蔽度与加权进界邻体直射荫蔽度中的各项参数进行寻优;以林下直射透射率与参数寻优后的尺度化加权直射荫蔽度、加权进界邻体直射荫蔽度间的Pearson、Spearman相关系数及线性回归决定系数为指标,评价尺度化加权直射荫蔽度、加权进界邻体直射荫蔽度对林下直射辐射的模拟性能。[结果]尺度化加权直射荫蔽度在最小邻体林木选取尺度(r_(min))与最大邻体林木选取尺度(r_(max))分别取6.332、13.609 m时,与阔叶红松林下直射透射率间具有较高的线性回归拟合精度,此时其对应的校正系数为10.440,与林下直射透射率间的Pearson、Spearman相关系数及线性回归决定系数分别为-0.581、-0.645及0.338。加权进界邻体直射荫蔽度在最大邻体林木选取临界值(T_(max))与最小邻体林木选取临界值(T_(min))分别为1.965与0.502时,与阔叶红松林下直射透射率间的线性回归拟合精度最高,此时其对应的校正系数为17.465,与林下太阳直射透射率间的Pearson、Spearman相关系数及线性回归决定系数分别为-0.738、-0.695与0.545。[结论]尺度化加权直射荫蔽度与加权进界邻体直射荫蔽度均能较好地反映林下太阳直射辐射,其中以加权进界邻体直射荫蔽度表现效果更优。在构建基于林木因子的林下直射辐射模拟模型时,应以合理地选取潜在影响林下直射辐射的邻体林木作为重点,同时应寻求能合理表达不同时刻林下直射辐射状态的简单方式。 展开更多
关键词 太阳辐射 直射透射率 尺度化加权直射荫蔽度 加权进界邻体直射荫蔽度 阔叶红松林
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杉楠异龄复层林光能利用效率研究
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作者 李寅荣 丁凯 +3 位作者 张毓婷 童再康 徐永宏 杨琪 《林业科学研究》 北大核心 2026年第1期10-20,共11页
[目的]研究探讨杉木、浙江楠在不同混交模式的光资源利用效率,为经营复层林和培育大径材的同时在林下培育珍贵用材提供理论依据。[方法]以杉木纯林(35龄杉木)、混交林A (35龄杉木与8龄浙江楠混交)与混交林B(24龄杉木与8龄浙江楠混交)为... [目的]研究探讨杉木、浙江楠在不同混交模式的光资源利用效率,为经营复层林和培育大径材的同时在林下培育珍贵用材提供理论依据。[方法]以杉木纯林(35龄杉木)、混交林A (35龄杉木与8龄浙江楠混交)与混交林B(24龄杉木与8龄浙江楠混交)为研究对象,分析杉木和浙江楠的生长、生化及光合生理变化。[结果]在混交林A中浙江楠淀粉和叶绿素含量较高,有利于抵御外界环境胁迫和维持较高的光合能力。混交林A中杉木和浙江楠的电子传递速率(ETR)和热耗散(NPQ)水平高于纯林和混交林B,即能够更高效地将光能转化为化学能,光保护能力更强。碳同化分析发现混交林中杉木净光合速率(P_(N))、气孔导度(G_(S))和蒸腾速率(T_(r))显著高于纯林,表明混交林A中杉木和浙江楠的生长更好。另外,浙江楠能够有效利用复层林下的光强,过多的光照不能被浙江楠有效利用。[结论]混交林A的经营模式最佳,有利于杉木大径材培育及浙江楠的生长量及固碳效率的提升。 展开更多
关键词 杉楠复层林 遮荫 生长影响 光合生理
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不同角度对X-Rite’s Shade Vision系统测量结果的影响 被引量:1
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作者 林芝 张秀华 +3 位作者 刘丽 朱形好 郑顺友 Y.LI 《口腔医学》 CAS 2006年第5期363-367,共5页
目的观察不同角度对X-Rite’s ShadeVision系统测量比色板结果的影响。方法将一副新的Vita16色比色板固定在粉红色的蜡中。X-Rite’s ShadeVision系统分别在平行于比色板唇面,5°、10°、15°向左右侧和切向、龈向倾斜时测... 目的观察不同角度对X-Rite’s ShadeVision系统测量比色板结果的影响。方法将一副新的Vita16色比色板固定在粉红色的蜡中。X-Rite’s ShadeVision系统分别在平行于比色板唇面,5°、10°、15°向左右侧和切向、龈向倾斜时测量颜色,以L*,a*,b*及Vita16色比色板色片颜色表示测量结果。计算ΔL,Δa,Δb和ΔE*ab,数据用单因素方差分析。结果向右倾斜5°、10°、15°时L*值分别减少0.22,0.97和0.93,而向左倾斜L*增加;垂直向角度改变时,L*值增加;最大的ΔL值在向龈向倾斜15°(2.84)和向切向倾斜15°(2.37),这导致相应位置出现最大的ΔE*ab(3.22±0.37)和(2.50±0.63),15°向左和右倾斜时,ΔE*ab分别为1.87±0.59和1.20±0.25。与其他位置比较,向龈向和切向15°时,ΔE*ab明显高(P<0.05)。结论X-Rite’sShadeVision测量时,正确的测量位置对获得准确的测量结果非常重要,角度的偏移,尤其是垂直向的倾斜会影响测量结果。 展开更多
关键词 X—Rite’s ShadeVision系统 测量 比色板
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