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广义Gamma分布弱湍流环境含指向误差串行中继水下无线光通信系统误码性能分析
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作者 王懿旭 李岳衡 +1 位作者 黄平 居美艳 《光子学报》 EI CAS CSCD 北大核心 2024年第2期37-51,共15页
鉴于目前普遍选用的水下弱湍流模型无法准确拟合实测数据的缺陷,选取经实验测试验证的广义Gamma分布来表征海洋弱湍流,以期合理评估受湍流等因素影响的水下无线光通信系统的误码性能。提出一种包含广义Gamma分布弱湍流、零/非零视轴指... 鉴于目前普遍选用的水下弱湍流模型无法准确拟合实测数据的缺陷,选取经实验测试验证的广义Gamma分布来表征海洋弱湍流,以期合理评估受湍流等因素影响的水下无线光通信系统的误码性能。提出一种包含广义Gamma分布弱湍流、零/非零视轴指向误差以及无衰落信道冲激响应隐路径损耗和多径效应的混合衰落信道模型,据此推导混合衰落串行中继无线光通信系统平均误码率的数学闭型表达;通过数值仿真验证所推导的误码率理论表达式的准确性,并考察不同系统核心参数对误码率的影响。研究结果表明:串行中继节点的引入可有效提高系统的误码性能,以零视轴指向误差、最终传输距离达45 m、误码率需求10-3为例,引入1至3个串行中继节点后,系统从一开始的无法工作,变为所需的发射功率分别降低至24 dBm、12 dBm和6 dBm;而光源初始发散角增大导致的无衰落信道冲激响应时延扩展,即符号间干扰,则会严重降低此性能改善。 展开更多
关键词 水下无线光通信 串行中继 性能分析 误码率 广义gamma分布
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一类折叠Gamma分布的尖峰厚尾性质及应用
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作者 陈明光 王源昌 《统计与决策》 北大核心 2024年第8期28-33,共6页
组合分布思想的出现及扩展为研究现实数据分布提供了优良方案。鉴于许多数据的尖峰后尾特征,文章从Gamma分布出发,构造了具有尖峰厚尾性质的折叠Gamma分布,进而讨论了折叠Gamma分布的性质,并在Newton-Raphson算法下给出了分布参数的矩... 组合分布思想的出现及扩展为研究现实数据分布提供了优良方案。鉴于许多数据的尖峰后尾特征,文章从Gamma分布出发,构造了具有尖峰厚尾性质的折叠Gamma分布,进而讨论了折叠Gamma分布的性质,并在Newton-Raphson算法下给出了分布参数的矩估计和极大似然估计,同时以数值模拟证明了估计的可行性,最后以实际数据对比研究折叠Gamma分布和正态分布的拟合效果。结果表明:折叠Gamma分布能更好地拟合尖峰厚尾数据,且其拟合效果随着数据样本量的增大而变好。 展开更多
关键词 折叠gamma分布 尖峰厚尾 gamma分布 金融收益率
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基于GAMMA软件二次开发的地表形变监测系统
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作者 曾伟 王泽平 杨红磊 《测绘通报》 CSCD 北大核心 2024年第10期163-167,共5页
InSAR技术具有大范围、高精度、全天时、全天候的优点,已被广泛地应用于地表形变监测与高程获取。GAMMA软件具有支持数据源丰富、处理功能全面、结果精度可靠和效率高等优势,是当前国际上常用的InSAR数据处理软件。但该软件采用命令行交... InSAR技术具有大范围、高精度、全天时、全天候的优点,已被广泛地应用于地表形变监测与高程获取。GAMMA软件具有支持数据源丰富、处理功能全面、结果精度可靠和效率高等优势,是当前国际上常用的InSAR数据处理软件。但该软件采用命令行交互,操作命令繁杂、对专业要求程度高,不易于非专业用户使用。针对以上问题,本文利用界面友好、开源的QGIS对GAMMA进行二次开发。结合GAMMA提供的py_gamma库和QGIS提供的py_QGIS API接口,采用模块化设计、算法并行优化等技术,开发了一套界面化InSAR形变监测系统,并以西藏沃达地区106景哨兵1号数据进行处理试验,从软件性能和处理结果方面证明了基于QGIS和GAMMA二次开发的可行性和可靠性。相关内容可为命令行用户界面软件转图形化用户界面提供参考。 展开更多
关键词 合成孔径雷达干涉测量 QGIS gamma 二次开发
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基于最大图像熵Gamma校正估计的图像特征点检测和匹配方法
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作者 苑朝 赵亚冬 +3 位作者 张耀 徐大伟 苑晶 翟永杰 《计量学报》 CSCD 北大核心 2024年第5期646-653,共8页
提出一种基于最大图像熵Gamma校正估计的图像特征点检测和匹配方法。通过预处理算法来增强图像的对比度,将其应用于图像特征点的检测和匹配。在预处理阶段,首先采用对数函数对图像进行归一化,根据设定的阈值将图像分为明亮和黑暗分量;... 提出一种基于最大图像熵Gamma校正估计的图像特征点检测和匹配方法。通过预处理算法来增强图像的对比度,将其应用于图像特征点的检测和匹配。在预处理阶段,首先采用对数函数对图像进行归一化,根据设定的阈值将图像分为明亮和黑暗分量;然后分别对两个分量自适应地选择不同的参数进行Gamma校正,并且确定使其熵最大化的校正参数为每个分量的最佳参数;最后将上述参数应用于Gamma校正生成对应原始图像明亮和黑暗区域的矫正图,并进行融合生成增强的图像。对预处理完的图像进行特征点检测和匹配实验。研究结果表明:所提出的算法相较于未处理算法、HE和自适应Gamma算法,特征点检测后的匹配数量在欠曝光图像上分别提升85.7%、26.4%和15.2%,在过曝光图像上分别提升59.4%、12.2%和103.8%。匹配效果也有较明显提升。 展开更多
关键词 机器视觉 特征点 图像熵 自适应 gamma校正 匹配效果
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基于Gamma混合模型的出租车落客行为
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作者 杨方宜 杨荣根 +1 位作者 李伟兵 何向东 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第3期589-598,共10页
为了更好地理解枢纽送站坪出租车落客行为,提高落客区域通行效率,提出基于Gamma混合模型的出租车落客决策模型.应用精确的出租车轨迹数据,将出租车停车时间分解为主动停车时间、被迫停车时间和落客时间,基于被迫停车时间分析构建等待耐... 为了更好地理解枢纽送站坪出租车落客行为,提高落客区域通行效率,提出基于Gamma混合模型的出租车落客决策模型.应用精确的出租车轨迹数据,将出租车停车时间分解为主动停车时间、被迫停车时间和落客时间,基于被迫停车时间分析构建等待耐性混合分布模型,模型验证结果与真实数据相吻合.在此基础上,以潜在乘客耐心分布、停车位置、期望停车位和行程时间为落客决策模型的核心指标,提取相关因子为解释变量,以是否落客为被解释变量,构建二元面板Logit模型,并对模型进行检验.结果表明,乘客耐心对车辆落客起着决定性的作用,落客决策模型预测准确率超过81%,表明该模型能够较好地预测出租车落客行为,为研究缓堵策略提供基础. 展开更多
关键词 客运枢纽 落客区域 gamma混合模型 落客决策 面板数据模型
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Effects of Gamma-Aminobutyric Acid on Performance of Lactating Sows during Heat Weather 被引量:3
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作者 ZHANG Ming CHEN Li-xlang FAN Zhi-yong WU Ying-song 《Animal Husbandry and Feed Science》 CAS 2009年第11期16-17,共2页
[ Objective] To study the effects of gamma-aminobutyric acid (GABA) on performance of lactating sows during heat stress. [ Metbod] A total of 14 sows at the same parity and with close expected date of childbirth and... [ Objective] To study the effects of gamma-aminobutyric acid (GABA) on performance of lactating sows during heat stress. [ Metbod] A total of 14 sows at the same parity and with close expected date of childbirth and similar body we:,ght were randomly divided into control group and experimental group. They were fed a common basal diet and a GABA (300 mg/kg) supplementary diet, respectively. The trial lasted for 21 d. [ Result ] The daily feed intake, lactation yield and average daily gain of piglets in the experimental group were increased by 9.4%, 28.5% and 10.7%, respectively. The backfat of lactating sows was decreased less, and the same with the weaning-oestrus interval. The survival ratio of piglets was increased by 4.5%. Compared with the control group, the content of lactose and fat increased significantly, but other components almost did not change. [Conclusien] Supplementing GABA in diet can improve the performance of lactating sows and promote the growth of piglets effectively. 展开更多
关键词 gamma-aminobutyric acid Lactating sows PIGLETS PERFORMANCE
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基于间断性Gamma校正的粘连蚕茧分割方法研究
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作者 邱舒敏 孙卫红 +1 位作者 邵铁锋 梁曼 《现代电子技术》 北大核心 2024年第16期180-186,共7页
目前,蚕茧分割计数研究主要针对大小几乎完全相同的蚕茧,难以应对大小差异较大的情况。针对上述问题,采用图像增强的方法提取蚕茧表面并进行蚕茧的粘连分割。首先,将原图直接转化为灰度图像进行腐蚀处理,通过Gamma校正使得图像灰度值收... 目前,蚕茧分割计数研究主要针对大小几乎完全相同的蚕茧,难以应对大小差异较大的情况。针对上述问题,采用图像增强的方法提取蚕茧表面并进行蚕茧的粘连分割。首先,将原图直接转化为灰度图像进行腐蚀处理,通过Gamma校正使得图像灰度值收缩;其次,通过限制对比度自适应直方图均衡化(CLAHE)方法提高蚕茧图像与其背景区域的灰度差,使其进一步分离;再利用高斯滤波和腐蚀方法平滑并收缩蚕茧图像,根据亮度数据进行第二次Gamma校正以调整对比度;最后,通过二值化处理统计连通域个数得出蚕茧数量。实验结果表明,所提方法针对大小蚕茧分割适应力较强,平均准确率高达99%。 展开更多
关键词 gamma校正 粘连蚕茧 图像分割 蚕茧计数 图像增强 限制对比度自适应直方图均衡化 高斯滤波
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Hippocampal and cortical expression of gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein in pentylenetetrazol-induced chronic epileptic rats 被引量:2
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作者 Yi Zeng Zhong Yang +1 位作者 Xiaodong Long Chao You 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第3期194-199,共6页
BACKGROUND: Gamma-aminobutyric acid transporter plays an important role in gamma-aminobutyric acid metabolism, and is highly associated with epilepsy seizures. Pathologically, astrocytes release active substances tha... BACKGROUND: Gamma-aminobutyric acid transporter plays an important role in gamma-aminobutyric acid metabolism, and is highly associated with epilepsy seizures. Pathologically, astrocytes release active substances that alter neuronal excitability, and it has been demonstrated that astrocytes play a role in epileptic seizures. OBJECTIVE: To observe changes in gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression in the hippocampus and cortex of the temporal lobe in rats with pentylenetetrazol-induced chronic epilepsy. DESIGN, TIME AND SETTING: Randomized, controlled, animal experiment was performed at the Department of Neurobiology, Third Military University of Chinese PLA between January 2006 and December 2007. MATERIALS: Pentylenetetrazol was purchased from Sigma, USA; rabbit anti-rat gammaaminobutyric acid transporter 1 and glial fibrillary acidic protein were from Chemicon, USA. METHODS: A total of 40 Sprague Dawley rats were divided into model and control groups. Rat models of chronic epilepsy were created by pentylenetetrazol kindling, and were subdivided into 3-, 7-, and 14-day kindling subgroups. MAIN OUTCOME MEASURES: Gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression, as well as the number of positive cells in the hippocampus and cortex of temporal lobe of rats, were determined by immunohistochemistry and Western blot analyses. RESULTS: Compared with the control group, the number of gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein -positive cells in the hippocampus and cortex of rats with pentylenetetrazol-induced epilepsy significantly increased, gamma-aminobutyric acid transporter 1 and glial fibrillary acidic protein expression increased after 3 days of kindling, reached a peak on day 7, and remained at elevated levels at day 14 (P〈 0.05). CONCLUSION: Astrocytic activation and gamma-aminobutyric acid transporter 1 overexpression may contribute to pentylenetetrazol-induced epilepsy. 展开更多
关键词 EPILEPSY glial fibrillary acidic protein gamma-aminobutyric acid transporter 1 oentvlenetetrazol astrocvte
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Gamma-aminobutyric acid A receptor and N-methyl-D-aspartate receptor subunit expression in rat spiral ganglion neurons 被引量:2
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作者 Xiaolan Tang Meng Gao Shuang Feng Jiping Su 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第13期1020-1024,共5页
BACKGROUND: Gamma-aminobutyric acid A (GABAA) and N-methyl-D-aspartate (NMDA) receptors are significant receptors in the central nervous system. An understanding of GABAA and NMDA receptor expression in spiral ga... BACKGROUND: Gamma-aminobutyric acid A (GABAA) and N-methyl-D-aspartate (NMDA) receptors are significant receptors in the central nervous system. An understanding of GABAA and NMDA receptor expression in spiral ganglion neurons (SGN) provides information for the functional role of these receptors in the auditory system. OBJECTIVE: To investigate mRNA expression of GABAA receptor (GABAAR) and NMDA receptor (NMDAR) subunits in the rat SGN. DESIGN, TIME AND SETTING: This in vitro, molecular biological study was performed at the Laboratory of Otolaryngology-Head and Neck Surgery, Guangxi Medical University, China from July 2007 to May 2008. MATERIALS: Reverse Transcriptase Kit and Taq DNA polymerase were purchased from Fermentas Burlington, ON, Canada; GABAAR and NMDAR primers were purchased from Shanghai Sangon, Shanghai, China. METHODS: SGN from 3-5 day postnatal Wistar rats was collected for primary cultures, mRNA expression of GABAAR and NMDAR subunits in the SGN was determined by reverse transcription polymerase chain reaction. MAIN OUTCOME MEASURES: Expression levels of GABAAR and NMDAR subunits were determined by quantitative analysis. RESULTS: GABAAR subunits (αl 6, β1 3, and y1 3) and NMDAR subunits (NR1, NR2A, NR2B, NR2C, NR2D, NR3A, and NR3B) were detected in the SGN. In α subunit genes of GABAAR, α1 and α3 expression was similar (P 〉 0.05) and greater than the other subunits. Of the β subunit genes, β1 subunit mRNA levels were greater than β2 and β3. Of the y subunit genes, y2 subunit mRNA levels were greater than y1 and y3. NR1 mRNA expression was the greatest of NMDAR subunits. CONCLUSION: GABAAR subunits (α1 6, β1-3, and y1-3) and NMDAR subunits (NR1, NR2A, NR2B, NR2C, NR2D, NR3A, and NR3B) were expressed in the rat SGN. Through comparison of GABAAR and NMDAR subunit expression, possible GABAAR combinations, as well as highly expressed subunit combinations, were estimated, which provided information for pharmacological and electrophysiological characteristics of GABAAR in the auditory system. 展开更多
关键词 spiral ganglion neuron gamma-aminobutyric acid A receptor N-methyl D-aspartate receptor reverse transcription polymerase chain reaction neural regeneration
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Gamma-Gamma信道下基于并行交织极化码的误码性能研究
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作者 蒋青芳 姚海峰 +3 位作者 刘智 刘树通 王宏利 郭昱佑 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2024年第1期145-152,共8页
为了降低大气湍流引起的衰落影响,同时减少长片误码干扰,提出一种基于并行交织极化码(polar code)的编码方法。通过蒙特卡洛模拟Gamma-Gamma分布的随机数构建大气湍流信道,以成对差错概率(pairwise error probability, PEP)和极化谱确... 为了降低大气湍流引起的衰落影响,同时减少长片误码干扰,提出一种基于并行交织极化码(polar code)的编码方法。通过蒙特卡洛模拟Gamma-Gamma分布的随机数构建大气湍流信道,以成对差错概率(pairwise error probability, PEP)和极化谱确定极化信道的误差概率上限,采用乘积距离准则最小化差错概率,建立了并行交织的设计准则。对极化码在湍流信道中的误码率(bit error rate, BER)性能进行了评估,仿真结果表明,基于极化码的并行交织方法获得了一个量级的误码性能提升,在信噪比为5 dB时,误码率从5.11×10-6降低为2.13×10-7,有效缓解了湍流引起的长片误码问题。实验验证了所提准则的可靠性和适用性。 展开更多
关键词 gamma-gamma信道 极化码 并行交织 成对差错概率
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Gamma3髓内钉在股骨粗隆间骨折手术治疗中的应用效果评价
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作者 束军潮 潘天明 陈凯 《系统医学》 2024年第2期102-105,共4页
目的探讨Gamma3髓内钉应用于股骨粗隆间骨折手术治疗中的效果。方法选择2020年1月—2022年12月丹阳市中医院收治的82例股骨粗隆间骨折患者为研究对象,以随机数表法分为对照组(n=41,给予抗旋型股骨近端髓内钉手术治疗)与观察组(n=41,给予... 目的探讨Gamma3髓内钉应用于股骨粗隆间骨折手术治疗中的效果。方法选择2020年1月—2022年12月丹阳市中医院收治的82例股骨粗隆间骨折患者为研究对象,以随机数表法分为对照组(n=41,给予抗旋型股骨近端髓内钉手术治疗)与观察组(n=41,给予Gamma3髓内钉手术治疗),比较两组患者的手术治疗相关指标、髋关节功能与并发症。结果两组患者的手术用时、手术总失血量对比,差异无统计学意义(P均>0.05)。观察组患者的住院时间(12.14±1.16)d、术后负重时间(5.63±1.07)周、骨折愈合时间(7.32±1.18)周均短于对照组,差异有统计学意义(t=12.535、9.884、6.992,P均<0.05)。与术前比较,两组患者术后1、3、6个月时的Harris评分均升高,差异有统计学意义(P均<0.05);但各时间段组间比较,差异无统计学意义(P均>0.05)。两组髋关节功能优良率、并发症发生率对比,差异无统计学意义(P均>0.05)。结论Gamma3髓内钉与抗旋型股骨近端髓内钉治疗股骨粗隆间骨折的效果、安全性均相当,但Gamma3髓内钉能加快患者术后功能恢复。 展开更多
关键词 股骨粗隆间骨折 gamma3髓内钉 抗旋型股骨近端髓内钉 并发症
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Genetic Enhancement of Indigenous Cowpea with Gamma-Ray Induced Trait Variation
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作者 Mathurin Tiergnin Dabiré Minimassom Philippe Nikiéma +10 位作者 Djibril Yonli Safiatou Sanna Wossoguim Josué Gouba Siébou Palé Hamidou Traoré Joseph T. B. Batieno Varra Prasad Zacharia Stewart Jan B. Middendorf Abhishek Rathore Anupama J. Hingane 《American Journal of Plant Sciences》 CAS 2024年第8期651-676,共26页
Production of cowpea (Vigna unguiculata (L.) Walp.), a staple legume crop in Sub-Saharan Africa, faces challenges due to biotic and abiotic constraints. Induced mutagenesis was deployed to create genetic variation in ... Production of cowpea (Vigna unguiculata (L.) Walp.), a staple legume crop in Sub-Saharan Africa, faces challenges due to biotic and abiotic constraints. Induced mutagenesis was deployed to create genetic variation in two cowpea varieties (KVX396-4-5-2D and Moussa local). The radio-sensitivity tests led to determe the lethal dose 50 (LD50) corresponding to 230 Gy and 220 Gy for KVX396-4-5-2D and Moussa local varieties, respectively. Dried seeds (M0) of each variety were gamma-ray irradiated with LD50 − 50, LD50 and LD50 + 50. M1 seeds were advanced to generate M2, M3 and M4 mutants using the single-seed-descent method. M4 mutant lines were evaluated in rain-fed conditions using a randomized complete block design to assess phenotypic differences. Data on seven qualitative and eleven quantitative traits were collected. The results indicated that the mutation induced variability in three qualitative traits: in KVX 396-4-5-2D mutant lines, with flower and seed color frequencies at 2.61% and 0.56% respectively, and pod dehiscence at a frequency of 0.24%. While in Moussa local mutants, a pod color changed at a frequency of 17%. ANOVA results revealed significant differences between mutants of both varieties for all quantitative traits, including photosynthetic parameters. Positive correlations were observed between leaf diameter and 100-seed weight, and between branch number and 100-seed weight. Hierarchical clustering revealed three clusters among KVX 396-4-5-2D mutants and six clusters among Moussa local mutants. Early maturity and high foliage were induced traits in Cluster 3 of KVX 396-4-5-2D mutants while high hundred-seed weight was induced in Cluster 6 of Moussa local mutants. 展开更多
关键词 COWPEA MUTAGENESIS gamma Rays Radio-Sensitivity PHENOTYPING
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改进Gamma变换的遥感影像阴影补偿方法
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作者 刘正才 董国庆 +1 位作者 谢文韬 姚湘军 《湘潭大学学报(自然科学版)》 CAS 2024年第3期94-102,共9页
影像阴影是遥感影像应用与解译的重要干扰项,为了提高阴影补偿精度,更真实地还原遥感影像上地物特征信息,提出一种基于提取同质区域的改进Gamma变换的阴影补偿方法.选取了两张具有不同地物特征的遥感影像作为实验区,首先对实验区影像进... 影像阴影是遥感影像应用与解译的重要干扰项,为了提高阴影补偿精度,更真实地还原遥感影像上地物特征信息,提出一种基于提取同质区域的改进Gamma变换的阴影补偿方法.选取了两张具有不同地物特征的遥感影像作为实验区,首先对实验区影像进行蓝光抑制;其次,通过膨胀运算和腐蚀运算求取阴影区域与非阴影同质区域,构造实验区所需要的结构元素;最后,针对同质区域通过Gamma变换对遥感影像进行阴影补偿,与Retinex算法和局部补偿算法进行精度比较.实验结果表明,该方法在每个颜色通道的平均梯度都要优于另外两种算法,从而验证了该文方法对提升遥感影像阴影补偿精度的有效性,为提高遥感影像阴影补偿精度提供了一种新思路. 展开更多
关键词 遥感影像 阴影补偿 gamma变换 同质区域
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Effects of Rhizoma Acori Tatarinowii extracts on gamma-aminobutyric acid type A receptor alpha 1 subunit brain expression during development in a recurrent seizure rat model 被引量:4
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作者 Liqun Liu Ding'an Mao +4 位作者 Keqiang Chi Xingfang Li Tao Bo Jinming Guo Zhuwen Yi 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第6期412-417,共6页
Extracts from Rhizoma Acori Tatarinowii (Grassleaf Sweetflag Rhizome, Shichangpu) have been shown to improve learning and memory, reduce anxiety, allay excitement, and suppress seizures. Rhizoma Acori Tatarinowii ex... Extracts from Rhizoma Acori Tatarinowii (Grassleaf Sweetflag Rhizome, Shichangpu) have been shown to improve learning and memory, reduce anxiety, allay excitement, and suppress seizures. Rhizoma Acori Tatarinowii extracts interact with y-aminobutyric acid and activate the y-aminobutyric acid type A receptor, although few studies have addressed the precise effects of v-aminobutyric acid type A receptor al subunit. In the present study, y-aminobutyric acid type A receptor al subunit protein expression in the cerebral cortex and hippocampus, and pathological scores of brain injury, were significantly greater following recurrent seizures, but significantly decreased following treatment with Rhizoma Acori Tatarinowii extracts. These results indicated that Rhizoma Acori Tatarinowii extracts down-regulated y-aminobutyric acid type A receptor al subunit protein expression in the cerebral cortex and hippocampus and protected seizure-induced brain injury during development. 展开更多
关键词 SEIZURE brain injury y-aminobutyric acid A receptor CORTEX HIPPOCAMPUS extracts of Rhizoma Acori Tatarinowii
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Relationship of nocturnal concentrations of melatonin, gamma-aminobutyric acid and total antioxidants in peripheral blood with insomnia after stroke: study protocol for a prospective non-randomized controlled trial 被引量:49
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作者 Wei Zhang Fang Li Tong Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第8期1299-1307,共9页
Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective si... Melatonin and gamma-aminobutyric acid(GABA) have been shown to regulate sleep. The nocturnal concentrations of melatonin, GABA and total antioxidants may relate to insomnia in stroke patients. In this prospective single-center non-randomized controlled clinical trial performed in the China Rehabilitation Research Center, we analyzed the relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke. Patients during rehabilitation of stroke were recruited and assigned to the insomnia group or non-insomnia group. Simultaneously, persons without stroke or insomnia served as normal controls. Each group contained 25 cases. The primary outcome was nocturnal concentrations of melatonin, GABA and total antioxidants in peripheral blood. The secondary outcomes were Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Morningness-Eveningness Questionnaire(Chinese version), and National Institute of Health Stroke Scale. The relationship of nocturnal concentrations of melatonin, GABA and total antioxidants with insomnia after stroke was analyzed and showed that they were lower in the insomnia group than in the non-insomnia group. The severity of stroke was higher in the insomnia group than in the non-insomnia group. Correlation analysis demonstrated that the nocturnal concentrations of melatonin and GABA were associated with insomnia after stroke. This trial was registered at Clinical Trials.gov, identifier: NCT03202121. 展开更多
关键词 nerve regeneration STROKE INSOMNIA MELATONIN γ-aminobutyric acid total antioxidants sleep-related scales National Institute ofHealth Stroke Scale neural regeneration
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Meta-analysis of the clinical efficacy of the Gamma3 nail vs Gamma3U-blade system in the treatment of intertrochanteric fractures
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作者 Xuan Wu Bo Gao 《World Journal of Orthopedics》 2024年第3期285-292,共8页
BACKGROUND The traditional Gamma3 nail is a mainstream treatment for femoral intertrochanteric fractures.Literature reports that the Gamma3U-blade system can increase the stability of the Gamma3 nail and reduce compli... BACKGROUND The traditional Gamma3 nail is a mainstream treatment for femoral intertrochanteric fractures.Literature reports that the Gamma3U-blade system can increase the stability of the Gamma3 nail and reduce complication incidence.However,comparative studies between the Gamma3U-blade and Gamma3 systems are limited;hence,this meta-analysis was performed to explore the clinical efficacy of these two surgical methods.AIM To investigate the clinical efficacy of Gamma3 and Gamma3 U-blade for intertrochanteric fractures.METHODS A computerized search for Chinese and English literature published from 2010 to 2022 was conducted in PubMed,Cochrane,CNKI,Wanfang,and VIP databases.The search keywords were gamma 3,gamma 3 U blade,and intertrochanteric fracture.Additionally,literature tracking was performed on the references of published literature.The data were analyzed using Revman 5.3 software.Two individuals checked the inputs for accuracy.Continuous variables were described using mean difference and standard deviation,and outcome effect sizes were expressed using ratio OR and 95%confidence interval(CI).High heterogeneity was considered at(P<0.05,I2>50%),moderate heterogeneity at I2 from 25%to 50%,and low heterogeneity at(P≥0.05,I2<50%).RESULTS Following a comprehensive literature search,review,and analysis,six articles were selected for inclusion in this study.This selection comprised five articles in English and one in Chinese,with publication years spanning from 2016 to 2022.The study with the largest sample size,conducted by Seungbae in 2021,included a total of 304 cases.Statistical analysis:A total of 1063 patients were included in this meta-analysis.The main outcome indicators were:Surgical time:The Gamma3U blade system had a longer surgical time compared to Gamma3 nails(P=0.006,I2=76%).Tip-apex distance:No statistical significance or heterogeneity was observed(P=0.65,I2=0%).Harris Hip score:No statistical significance was found,and low heterogeneity was detected(P=0.26,I2=22%).Union time:No statistical significance was found,and high heterogeneity was detected(P=0.05,I2=75%).CONCLUSION Our study indicated that the Gamma3 system reduces operative time compared to the Gamma3 U-blade system in treating intertrochanteric fractures.Both surgical methods proved to be safe and effective for this patient group.These findings may offer valuable insights and guidance for future surgical protocols in hip fracture patients. 展开更多
关键词 gamma3 nail gamma3U-Blade system Femoral intertrochanteric fractures META-ANALYSIS
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Probability Laws Derived from the Gamma Function
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作者 Lansana Toure Soumaila Conde 《Open Journal of Statistics》 2024年第1期106-118,共13页
Several densities or probability laws of continuous random variables derive from the Euler Gamma function. These laws form the basis of sampling theory, namely hypothesis testing and estimation. Namely the gamma, beta... Several densities or probability laws of continuous random variables derive from the Euler Gamma function. These laws form the basis of sampling theory, namely hypothesis testing and estimation. Namely the gamma, beta, and Student law, through the chi-square law and the normal law are all distributions resulting from applications of Euleur functions. 展开更多
关键词 gamma Function Beta Function PROBABILITY Degree of Freedom
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Analysis of Progressively Type-Ⅱ Inverted Generalized Gamma Censored Data and Its Engineering Application
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作者 Refah Alotaibi Sanku Dey Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期459-489,共31页
A novel inverted generalized gamma(IGG)distribution,proposed for data modelling with an upside-down bathtub hazard rate,is considered.In many real-world practical situations,when a researcher wants to conduct a compar... A novel inverted generalized gamma(IGG)distribution,proposed for data modelling with an upside-down bathtub hazard rate,is considered.In many real-world practical situations,when a researcher wants to conduct a comparative study of the life testing of items based on cost and duration of testing,censoring strategies are frequently used.From this point of view,in the presence of censored data compiled from the most well-known progressively Type-Ⅱ censoring technique,this study examines different parameters of the IGG distribution.From a classical point of view,the likelihood and product of spacing estimation methods are considered.Observed Fisher information and the deltamethod are used to obtain the approximate confidence intervals for any unknown parametric function of the suggestedmodel.In the Bayesian paradigm,the same traditional inferential approaches are used to estimate all unknown subjects.Markov-Chain with Monte-Carlo steps are considered to approximate all Bayes’findings.Extensive numerical comparisons are presented to examine the performance of the proposed methodologies using various criteria of accuracy.Further,using several optimality criteria,the optimumprogressive censoring design is suggested.To highlight how the proposed estimators can be used in practice and to verify the flexibility of the proposed model,we analyze the failure times of twenty mechanical components of a diesel engine. 展开更多
关键词 Inverted generalized gamma CENSORING spacing function LIKELIHOOD Bayesian optimal plan
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Gamma Approximation Based Multi-Antenna Covert Communication Detection
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作者 Wan Pengwu Chen Dongrui +2 位作者 Wang Danyang Hui Xi Peng Kang 《China Communications》 SCIE CSCD 2024年第9期90-97,共8页
Covert communication technology makes wireless communication more secure,but it also provides more opportunities for illegal users to transmit harmful information.In order to detect the illegal covert communication of... Covert communication technology makes wireless communication more secure,but it also provides more opportunities for illegal users to transmit harmful information.In order to detect the illegal covert communication of the lawbreakers in real time for subsequent processing,this paper proposes a Gamma approximation-based detection method for multi-antenna covert communication systems.Specifically,the Gamma approximation property is used to calculate the miss detection rate and false alarm rate of the monitor firstly.Then the optimization problem to minimize the sum of the missed detection rate and the false alarm rate is proposed.The optimal detection threshold and the minimum error detection probability are solved according to the properties of the Lambert W function.Finally,simulation results are given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 covert communication DETECTION gamma approximation Lambert W function multi-antenna technique
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Expression of gamma-aminobutyric acid type A receptor α_2 subunit in the dorsal root ganglion of rats with sciatic nerve injury 被引量:1
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作者 Yu Lian Yang Wang +5 位作者 Ketao Ma Lei Zhao Zhongshuang Zhang Yuanyuan Shang Junqiang Si Li Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第32期2492-2499,共8页
The γ-aminobutyric acid neurotransmitter in the spinal cord dorsal horn plays an important role in pain modulation through primary afferent-mediated presynaptic inhibition. The weakening of γ-aminobutyric acid-media... The γ-aminobutyric acid neurotransmitter in the spinal cord dorsal horn plays an important role in pain modulation through primary afferent-mediated presynaptic inhibition. The weakening of γ-aminobutyric acid-mediated presynaptic inhibition may be an important cause of neuropathic pain. γ-aminobutyric acid-mediated presynaptic inhibition is related to the current strength of γ-aminobutyric acid A receptor activation. In view of this, the whole-cell patch-clamp technique was used here to record the change in muscimol activated current of dorsal root ganglion neurons in a chronic constriction injury model. Results found that damage in rat dorsal root ganglion neurons following application of muscimol caused concentration-dependent activation of current, and compared with the sham group, its current strength and γ-aminobutyric acid A receptor protein expression decreased. Immunofluorescence revealed that γ-aminobutyric acid type A receptor α2 subunit protein expression decreased and was most obvious at 12 and 15 days after modeling. Our experimental findings confirmed that the y-aminobutyric acid type A receptor α2 subunit in the chronic constriction injury model rat dorsal root ganglion was downregulated, which may be one of the reasons for the reduction of injury in dorsal root ganglion neurons following muscimol-activated currents. 展开更多
关键词 γ-aminobutyric acid γ-aminobutyric acid type A receptor α2 subunit neuropathic pain dorsal root ganglion whole-cell patch clamp IMMUNOFLUORESCENCE primary afferent depolarization paw withdrawal latency MUSCIMOL
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