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Preface to Special Issue on Towards High Performance Ga_(2)O_(3) Electronics: Epitaxial Growth and Power Devices(Ⅰ)
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作者 Genquan Han Shibing Long +2 位作者 Yuhao Zhang Yibo Wang Zhongming Wei 《Journal of Semiconductors》 EI CAS CSCD 2023年第6期4-6,共3页
There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power ... There is currently great optimism within the electronics community that gallium oxide(Ga_(2)O_(3)) ultra-wide bandgap semiconductors have unprecedented prospects for eventually revolutionizing a rich variety of power electronic applications. Specially, benefiting from its ultra-high bandgap of around 4.8 eV, it is expected that the emerging Ga_(2)O_(3) technology would offer an exciting platform to deliver massively enhanced device performance for power electronics and even completely new applications. 展开更多
关键词 Epitaxial growth and power Devices Preface to Special Issue on Towards High Performance Ga_(2)O_(3)Electronics power
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The Fractional Power Law of Wind Wave Growth in Deep Water for Short Fetch 被引量:1
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作者 GUANChanglong SUNQun PhilippeFraunie 《Journal of Ocean University of Qingdao》 2002年第2期105-108,共4页
Combining the 3/2 power law proposed by Toba with the significant wave energy balance equation for wind waves, wave growth in deep water for short fetch is investigated. It is found that the variations of wave height ... Combining the 3/2 power law proposed by Toba with the significant wave energy balance equation for wind waves, wave growth in deep water for short fetch is investigated. It is found that the variations of wave height and period with fetch have the form of power function with fractional exponents 3/8 and 1/4 respectively. Using these exponents in the power functions and through data fitting, the concise wind wave growth relations for short fetch are obtained. 展开更多
关键词 风波增长率 分数幂律 统计特征 海平面 能量平衡方程
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Correlation analysis of economic growth and development of electric power
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作者 Ge Pan 《International Journal of Technology Management》 2014年第2期12-14,共3页
关键词 经济增长 电力需求 相关性分析 电力行业 电力发展规划 经济发展 经济形势 研究机构
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Wind power airs growth plan
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《Electricity》 1996年第1期53-53,共1页
The Dabancheng Windpower Farm in Northwest China’s Xinjiang Uygur Autonomous Region, the largest of its kind in China, plans to increase its present generating capacity of 10 MW to 100 MW by the year 2000. Situated i... The Dabancheng Windpower Farm in Northwest China’s Xinjiang Uygur Autonomous Region, the largest of its kind in China, plans to increase its present generating capacity of 10 MW to 100 MW by the year 2000. Situated in the vast desert to the southeast of Urumqi, capital city of Xinjiang, the farm has bountiful wind energy resources, with wind speeds as high as 38 metres per second. First built with the help of Danish Government loans in 1992, the farm now provides electricity for local people, especially those in remote areas which are not connected to a power grid. The farm is now seeking both domestic and overseas cooperation for technological improvements and expansion, according 展开更多
关键词 Wind power airs growth plan HIGH
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$8O million power contract to fuel Heilongjiang growth
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《Electricity》 1996年第1期53-53,共1页
An $ 80 million contract was clinched on March 14, 1996 for Japanese Mitsui & Co Ltd to provide generating equipment for the Qitaihe Power Plant in Northeast Heilongjiang Province. The deal was signed in Beijing b... An $ 80 million contract was clinched on March 14, 1996 for Japanese Mitsui & Co Ltd to provide generating equipment for the Qitaihe Power Plant in Northeast Heilongjiang Province. The deal was signed in Beijing by the China National Technical Import and Export Corp. (CNTIC), China Electrical Power Technology Import and Export Corp, Heilongiiang Electrical Power Corp and Mitsui. Under the contract, the Qitaihe Power Plant will import two 350 MW generating units from Mitsui, of which the generators will 展开更多
关键词 million power contract to fuel Heilongjiang growth WILL Co
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Nuclear power industry's growth set to slow
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《Electricity》 2011年第4期31-31,共1页
According to the report of China Daily, influenced by the nuclear accidents in Japan, the expansion of China's nuclear power industry will slow from the rapid rate of the 11 th
关键词 THAN WORK Nuclear power industry’s growth set to slow
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Advancement in Science and Technology Enhanced the Growth of China's Electric Power Industry
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《Electricity》 1996年第2期19-22,共4页
Within the seven years’ period from 1987 to 1994. the total installed capacity of China’s electric power industry doubled from 100 GW to 200 GW. This high rate of growth has imposed new and more stringent requiremen... Within the seven years’ period from 1987 to 1994. the total installed capacity of China’s electric power industry doubled from 100 GW to 200 GW. This high rate of growth has imposed new and more stringent requirements on all the branches in the 展开更多
关键词 In Advancement in Science and Technology Enhanced the growth of China’s Electric power Industry THAN
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百年变局与大国关系的中长期演变
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作者 钟飞腾 《学术前沿》 北大核心 2024年第6期54-66,共13页
在百年未有之大变局视角下,大国力量最本质和持久的因素仍然是经济力量。看待中美经济力量变化时,既要重视短期变化,但更要重视长期趋势。从短期来看,中国经济总量赶超美国经济总量的速度有所减缓,但仍存在超越美国的可能。从长期来看,... 在百年未有之大变局视角下,大国力量最本质和持久的因素仍然是经济力量。看待中美经济力量变化时,既要重视短期变化,但更要重视长期趋势。从短期来看,中国经济总量赶超美国经济总量的速度有所减缓,但仍存在超越美国的可能。从长期来看,基于PPP测算的经济力量对比,将康德拉季耶夫周期和权力转移理论相结合,有助于更好地理解国际冲突和地缘政治变化。由于收入水平较低的国家基于上述两种算法会有不同的经济地位,而这种差别是造成近年来俄罗斯和印度在国际舞台上冲突性行动加剧的重要原因。日本因为熟悉政府能力与经济增长的复杂关系,倾向于低估中国的长期经济增长前景,进而导致日本在战略上始终追随美国。不过,俄乌冲突使美国组建包括欧盟、日本和印度在内的大联盟的成效大打折扣。 展开更多
关键词 百年未有之大变局 经济增长 康德拉季耶夫周期 权力转移理论
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DBD等离子体与活化水对马铃薯生长特性及产量的影响
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作者 李平 陶华杨 +3 位作者 彭超 王超群 陈思乐 陈兆权 《高电压技术》 EI CAS CSCD 北大核心 2024年第4期1742-1751,共10页
等离子体技术在农业生产、生物医学、环境保护等领域有着广泛的应用前景。论文采用多针-板电极制备等离子体活化水装置、板-板电极等离子体直接处理马铃薯装置,对比研究了不同放电功率下等离子体活化水、直接等离子体处理对马铃薯生长... 等离子体技术在农业生产、生物医学、环境保护等领域有着广泛的应用前景。论文采用多针-板电极制备等离子体活化水装置、板-板电极等离子体直接处理马铃薯装置,对比研究了不同放电功率下等离子体活化水、直接等离子体处理对马铃薯生长特性及产量的影响。2种装置均呈丝状放电,且放电功率与外施电压正相关;当最佳放电功率匹配时,等离子体活化水、直接等离子体处理均能显著改善马铃薯生长特性及产量。等离子体活化水的放电功率为53 W时,马铃薯植株高度、茎粗、鲜重、叶绿素质量分数及产量分别提升了6.4%、18.9%、25.9%、31.7%及17.5%;直接等离子体处理马铃薯的放电功率为8 W时,植株的各参数值增幅均在10%以上。研究结果表明:放电功率变化时,等离子体活化水的理化参数(pH值、氧化还原电位、电导率、过氧化氢、硝酸根离子、亚硝酸根离子)变化显著;随着放电功率的提升,直接等离子体处理的马铃薯吸水率先增长后下降,种皮刻蚀逐渐明显。论文的研究可为DBD等离子体与活化水在农业生产领域应用提供参考。 展开更多
关键词 DBD 等离子体活化水 直接等离子体处理 放电功率 马铃薯生长特性
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GDP国际比较方法及中美GDP相对变化趋势
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作者 李兆辰 韩天阔 高宇宁 《贵州财经大学学报》 北大核心 2024年第1期11-20,共10页
GDP是衡量国家经济规模和世界经济格局的关键指标,然而在理论和实践中对于GDP国际比较方法尚未形成共识。本文阐释了GDP国际比较的三类主要方法及各自的特点与局限,认为其本质差异在于转换因子的选择,在此基础上分析了中美GDP在1990~202... GDP是衡量国家经济规模和世界经济格局的关键指标,然而在理论和实践中对于GDP国际比较方法尚未形成共识。本文阐释了GDP国际比较的三类主要方法及各自的特点与局限,认为其本质差异在于转换因子的选择,在此基础上分析了中美GDP在1990~2020年的相对变化趋势,分别从总量视角和分产业分行业的结构视角进行分析。研究发现,中国GDP迅速追赶美国,尤其在制造业方面显著超越美国,但是不同方法测算的相对变动程度差异较大。汇率法在计算上较为简便,但受到汇率波动等因素的影响较大;购买力平价法在原理上较为合理,但在操作性和可比性上较弱;替代法在数据上较为可靠,但理论依据和客观性较弱。本研究深化了对于GDP国际比较方法理论本质的认识,测算了中美GDP总量和结构的相对变化趋势,可为进一步完善GDP国际比较方法提供借鉴。 展开更多
关键词 国内生产总值 国际比较 购买力平价 经济增长 GDP
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基于FP-Growth算法和GRNN的电力知识文本挖掘 被引量:9
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作者 白勇 张占龙 熊隽迪 《计算机科学》 CSCD 北大核心 2021年第8期86-90,共5页
为了提高电力知识文本挖掘的性能,采用FP-Growth算法对影响电力需求的强关联因素进行挖掘,运用广义回归神经网络(General Regression Neural Network,GRNN)算法实现电力需求预测。首先,对待挖掘的电力文本进行指标提取并编码,生成电力... 为了提高电力知识文本挖掘的性能,采用FP-Growth算法对影响电力需求的强关联因素进行挖掘,运用广义回归神经网络(General Regression Neural Network,GRNN)算法实现电力需求预测。首先,对待挖掘的电力文本进行指标提取并编码,生成电力文本初始FP-Tree;接着采用FP-Growth算法遍历所有FP-Tree,生成频繁集,过滤掉小于最小支持度的项,留下频数较高的频繁项;然后根据更新后的FP-Tree统计关联项,选择与总用电量增长率关联强的变量生成训练样本;最后采用GRNN算法对电力需求文本进行训练,输入电力需求预测样本,设置平滑因子,通过模式层的输出和加权求和来获得电力需求预测结果。实验结果证明,通过合理设置最小支持度和GRNN的平滑因子,能够获得较好的电力文本挖掘性能,与常用挖掘算法相比,所提算法能够获得更高的电力需求预测准确率。 展开更多
关键词 电力文本挖掘 FP-growth算法 广义回归神经网络 平滑因子 频繁集
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从骆秉章抚湘看咸丰朝权势的汉长满消
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作者 王毓伟 刘志鸿 《青岛农业大学学报(社会科学版)》 2024年第1期91-97,125,共8页
太平天国运动爆发后,骆秉章两次抚湘,时长近十年。因八旗、绿营屡战屡败,清朝遂将军事希望寄托于湘军等团练武装。由此引发兵权转移。抚湘近十年的骆秉章在其中扮演的角色不亚于曾国藩。为激励湘军作战以挽救清朝统治,骆秉章大行保举,... 太平天国运动爆发后,骆秉章两次抚湘,时长近十年。因八旗、绿营屡战屡败,清朝遂将军事希望寄托于湘军等团练武装。由此引发兵权转移。抚湘近十年的骆秉章在其中扮演的角色不亚于曾国藩。为激励湘军作战以挽救清朝统治,骆秉章大行保举,并力求清廷让戴罪之能人留营效力。出于人文关怀和激励将弁死战之目的,骆秉章不断上奏,请求抚恤和褒奖阵亡将士。骆秉章为君分忧,却无意间推动汉人逐渐握有兵权,掌控地方,并帮助汉人在精神文化领域建立起满人无法比拟的形象,促成了咸丰时期权势的汉长满消。 展开更多
关键词 骆秉章 抚湘 权势 汉长满消
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早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限的相关性
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作者 汤倩 姜海娜 +1 位作者 韩宏霞 邓金凤 《中国实验诊断学》 2024年第2期173-178,共6页
目的 分析早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限(FGR)的相关性。方法 选取76例于天津中医药大学附属北辰中医医院2021年4月—2022年9月进行早孕期NT检查的孕妇为研究对象,根据胎儿是否存在生长受限... 目的 分析早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限(FGR)的相关性。方法 选取76例于天津中医药大学附属北辰中医医院2021年4月—2022年9月进行早孕期NT检查的孕妇为研究对象,根据胎儿是否存在生长受限分为对照组69例,FGR组7例。以此对比产妇基本资料,两组超声参数:胎盘血管化指数(VI)、胎盘血流指数(FI)、血管化-血流指数(VFI)、子宫动脉阻力指数(UtA-RI)、子宫动脉搏动指数(UtA-PI)、胎儿静脉导管搏动指数(DV-PI),分析发生FGR独立危险因素,超声参数与FGR的相关性,ROC曲线分析不同指标预测FGR的效能。结果 FGR与年龄、BMI指数、孕期贫血、产次无关,无统计学差异(P>0.05);主要与胎膜早破、羊水过少、脐带异常、胎粪污染、胎盘异常有关,具有统计学差异(P<0.05)。与对照组相比,FGR组VI、VFI、水平较低,UtA-RI、UtA-PI、DV-PI水平有所提升(P<0.05)。以FGR为因变量(0=否,1=是),建立Logistic回归模型,结果显示,VI、VFI、UtA-RI、UtA-PI、DV-PI是导致FGR的独立危险因素(P<0.05)。VI、VFI参数与FGR呈负相关;UtA-RI、UtA-PI、DV-PI参数与FGR呈正相关(P<0.05)。ROC曲线显示,VI、VFI、UtA-RI、UtA-PI、DV-PI单一及联合预测均有较高效能,而联合检查预测价值最高(P<0.05)。结论 早孕期采用三维能量多普勒联合频谱多普勒预测FGR的效能较高,有助于早期诊断并及时采取干预措施。 展开更多
关键词 胎儿生长受限 三维能量多普勒 频谱多普勒 胎盘血流灌注 相关性
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基于预期盈余增长的质量测度与定价能力
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作者 刘月立 金秀 于金明 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期145-152,共8页
从质量溢价驱动因素视角构建基于预期盈余增长(expected earnings growth,EEG)的质量测度指标,分析该指标与股票预期收益的关系,进一步构造EEG质量因子并将其纳入Fama-French三因子模型,研究该因子的定价能力.研究发现:EEG质量测度指标... 从质量溢价驱动因素视角构建基于预期盈余增长(expected earnings growth,EEG)的质量测度指标,分析该指标与股票预期收益的关系,进一步构造EEG质量因子并将其纳入Fama-French三因子模型,研究该因子的定价能力.研究发现:EEG质量测度指标可以衡量公司的预期盈余增长;EEG质量测度指标与股票预期收益显著正相关,表明EEG质量溢价显著存在;EEG质量因子对股票横截面组合收益的解释能力较强;引入EEG质量因子的四因子模型比Fama-French类模型具有更高的定价效率.研究结论可以丰富资产定价相关理论,为投资者理性决策、监管者培育良好投资理念和提升市场定价效率提供参考. 展开更多
关键词 预期盈余增长 EEG质量测度指标 股票预期收益 定价能力 四因子模型
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Analytically Derived Wind Wave Growth Relations 被引量:10
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作者 GUAN Changlong(管长龙) +1 位作者 SUN Qun(孙群) 《China Ocean Engineering》 SCIE EI 2002年第3期359-368,共10页
By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation forwind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth rel... By the use of the 3/2 power law presented by Toba combined with the significant wave energy balance equation forwind wave, wind wave growth at a limited fetch is analytically investigated. The new wind wave growth relations(WWGRs) are analytically derived with sheltering coefficient and wind drag coefficient as parameters. The geometricalaverage of observational values of sheltering coefficient and the arithmetic average of observational values of wind drag co-efficient are applied to determine the new WWGRs. Comparisons with existing empirical WWGRs are made. 展开更多
关键词 WIND WAVE WIND WAVE growth RELATION 3/2 powerlaw
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基于FP-Growth的电力系统故障预测方法 被引量:3
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作者 潘磊 《软件导刊》 2020年第10期152-155,共4页
为了提高电力系统中故障预测效率及便捷性,提出一种基于FP-Growth算法的电力系统故障预测方法,无需先验知识及人工标注,便可从海量历史日志数据中快速提取出故障信息模式,并基于实时日志数据对未来可能发送的系统故障进行预测。该方法... 为了提高电力系统中故障预测效率及便捷性,提出一种基于FP-Growth算法的电力系统故障预测方法,无需先验知识及人工标注,便可从海量历史日志数据中快速提取出故障信息模式,并基于实时日志数据对未来可能发送的系统故障进行预测。该方法首先根据电力系统不同类型的日志特征对原始数据进行预处理,然后基于FP-Growth算法挖掘日志中与故障事件相关的关联规则,并使用关联规则进行故障匹配,从而达到预测效果。算法经过真实电力系统日志数据集测试,结果表明该故障预测方法平均准确率为89.5%,平均召回率为79.8%,且执行效率较高,节省了业务人员50%以上的时间。 展开更多
关键词 FP-growth 电力系统日志 关联规则 故障预测 日志挖掘
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Estimate of China's energy carbon emissions peak and analysis on electric power carbon emissions 被引量:6
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作者 WANG Zhi-Xuan ZHANG Jing-Jie +2 位作者 PAN Li YANG Fan SHI Li-Na 《Advances in Climate Change Research》 SCIE 2014年第4期181-188,共8页
China's energy carbon emissions are projected to peak in 2030 with approximately 110%of its 2020 level under the following conditions:1)China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in ... China's energy carbon emissions are projected to peak in 2030 with approximately 110%of its 2020 level under the following conditions:1)China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in 2030;2)coal's share of the energy consumption is 61%in 2020 and55%in 2030;3)non-fossil energy's share increases from 15%in 2020 to 20%in 2030;4)through 2030,China's GDP grows at an average annual rate of 6%;5)the annual energy consumption elasticity coefficient is 0.30 in average;and 6)the annual growth rate of energy consumption steadily reduces to within 1%.China's electricity generating capacity would be 1,990 GW,with 8,600 TW h of power generation output in 2020.Of that output 66%would be from coal,5%from gas,and 29%from non-fossil energy.By 2030,electricity generating capacity would reach3,170 GW with 11,900 TW h of power generation output.Of that output,56%would be from coal,6%from gas,and 37%from non-fossil energy.From 2020 to 2030,CO2emissions from electric power would relatively fall by 0.2 Gt due to lower coal consumption,and relatively fall by nearly 0.3 Gt with the installation of more coal-fired cogeneration units.During 2020e2030,the portion of carbon emissions from electric power in China's energy consumption is projected to increase by 3.4 percentage points.Although the carbon emissions from electric power would keep increasing to 118%of the 2020 level in 2030,the electric power industry would continue to play a decisive role in achieving the goal of increase in non-fossil energy use.This study proposes countermeasures and recommendations to control carbon emissions peak,including energy system optimization,green-coal-fired electricity generation,and demand side management. 展开更多
关键词 能源消费弹性系数 二氧化碳排放量 电力行业 排放分析 化石能源 估计 峰值 热电联产机组
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Low-power laser irradiation inhibits arecoline-induced fibrosis:an in vitro study 被引量:2
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作者 Mei-Chun Yeh Ker-Kong Chen +4 位作者 Min-Hsuan Chiang Chia-Hsin Chen Ping-Ho Chen Huey-Er Lee Yan-Hsiung Wang 《International Journal of Oral Science》 SCIE CAS CSCD 2017年第1期38-42,共5页
Oral submucous fibrosis(OSF) is a potentially malignant disorder that is characterized by a progressive fibrosis in the oral submucosa. Arecoline, an alkaloid compound of the areca nut, is reported to be a major aetio... Oral submucous fibrosis(OSF) is a potentially malignant disorder that is characterized by a progressive fibrosis in the oral submucosa. Arecoline, an alkaloid compound of the areca nut, is reported to be a major aetiological factor in the development of OSF. Low-power laser irradiation(LPLI) has been reported to be beneficial in fibrosis prevention in different damaged organs.The aim of this study was to investigate the potential therapeutic effects of LPLI on arecoline-induced fibrosis. Arecolinestimulated human gingival fibroblasts(HGFs) were treated with or without LPLI. The expression levels of the fibrotic marker genes alpha-smooth muscle actin(α-SMA) and connective tissue growth factor(CTGF/CCN2) were analysed by quantitative realtime reverse transcription polymerase chain reaction(RT-PCR) and western blots. In addition, the transcriptional activity of CCN2 was further determined by a reporter assay. The results indicated that arecoline increased the messenger RNA and protein expression of CCN2 and α-SMA in HGF. Interestingly, both LPLI and forskolin, an adenylyl cyclase activator, reduced the expression of arecoline-mediated fibrotic marker genes and inhibited the transcriptional activity of CCN2. Moreover, pretreatment with SQ22536, an adenylyl cyclase inhibitor, blocked LPLI's inhibition of the expression of arecoline-mediated fibrotic marker genes. Our data suggest that LPLI may inhibit the expression of arecoline-mediated fibrotic marker genes via the c AMP signalling pathway. 展开更多
关键词 adenylate cyclase alpha-smooth muscle actin connective tissue growth factor FIBROSIS low-power laser irradiation
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Mobile user forecast and power-law acceleration invariance of scale-free networks 被引量:1
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作者 郭进利 郭曌华 刘雪娇 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期548-555,共8页
This paper studies and predicts the number growth of China’s mobile users by using the power-law regression.We find that the number growth of the mobile users follows a power law.Motivated by the data on the evolutio... This paper studies and predicts the number growth of China’s mobile users by using the power-law regression.We find that the number growth of the mobile users follows a power law.Motivated by the data on the evolution of the mobile users,we consider scenarios of self-organization of accelerating growth networks into scale-free structures and propose a directed network model,in which the nodes grow following a power-law acceleration.The expressions for the transient and the stationary average degree distributions are obtained by using the Poisson process.This result shows that the model generates appropriate power-law connectivity distributions.Therefore,we find a power-law acceleration invariance of the scale-free networks.The numerical simulations of the models agree with the analytical results well. 展开更多
关键词 无标度网络 移动用户 幂律 用户预测 变性 网络模型 用户数量 回归预测
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基于FP-growth算法的电网运行风险分析
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作者 邓智广 《通信电源技术》 2020年第21期9-10,14,共3页
由于传统分析方法没有构造电网运行风险分析FP-tree进行关联分析,因此风险误报率高。针对这一问题,提出基于FP-growth算法的电网运行风险分析,通过构造电网运行风险分析FP-tree,挖掘电网运行风险关键线路,分析电网运行风险。设计仿真实... 由于传统分析方法没有构造电网运行风险分析FP-tree进行关联分析,因此风险误报率高。针对这一问题,提出基于FP-growth算法的电网运行风险分析,通过构造电网运行风险分析FP-tree,挖掘电网运行风险关键线路,分析电网运行风险。设计仿真实验结果表明,所设计方法风险误报率最高为0.249%,实验对照组为0.496%,可以实现对电网运行风险的精准分析。 展开更多
关键词 FP-growth算法 电网 运行风险 分析
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