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Focus: Cultural Issues During the 2018 NPC and CPPCC
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作者 Xue Shuai Zhang Jing 《China & The World Cultural Exchange》 2018年第4期8-15,共8页
关键词 npc 中华人民共和国 文化
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SAFE AND HARMONIOUS TIBET AN INTERVIEW WITH THE REPRESENTATIVES OF NPC AND CPPCC
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作者 ZHOU AIMING 《China's Tibet》 2007年第4期20-27,2,共9页
In March,the annual national conferences-the 5th Session of the 10th National People's Congress(NPC)and the 5th Session of the 10th National People's Politic Consultative Congress (CPPCC),were held in Beijing.... In March,the annual national conferences-the 5th Session of the 10th National People's Congress(NPC)and the 5th Session of the 10th National People's Politic Consultative Congress (CPPCC),were held in Beijing.35 representatives and members of NPC and CPPCC from Tibet Autonomous Region(TAR) took part into these two big conventions. 展开更多
关键词 AR npc
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The NPC and CPPCC Sessions Draw Worldwide Attention
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《China Today》 2010年第4期24-25,共2页
THE eyes and ears of the country are turned every March to the annual sessions of the National People’s Congress (NPC) and Chinese People’s Political Consultative Conference (CPPCC), and increasingly so is worldwide... THE eyes and ears of the country are turned every March to the annual sessions of the National People’s Congress (NPC) and Chinese People’s Political Consultative Conference (CPPCC), and increasingly so is worldwide attention. 展开更多
关键词 中国人民政治协商会议 全国人民代表大会 协会 人民政协 npc 世界性 外交部 媒体
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NPC三电平整流器的混合参数自适应控制
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作者 牛小兵 董文浩 +1 位作者 石洁 周鑫 《上海海事大学学报》 北大核心 2024年第1期104-110,共7页
为降低中点箝位型(neutral point clamped,NPC)三电平整流器的电流谐波,在dq同步旋转坐标系下推导出带中点电压耦合项的NPC三电平整流器数学模型,并分析中点电压对电流控制的影响。对模型中的中点电压耦合项和交流侧等效电阻会增大电流... 为降低中点箝位型(neutral point clamped,NPC)三电平整流器的电流谐波,在dq同步旋转坐标系下推导出带中点电压耦合项的NPC三电平整流器数学模型,并分析中点电压对电流控制的影响。对模型中的中点电压耦合项和交流侧等效电阻会增大电流谐波及无法通过常规方法进行准确估计的问题,设计一种混合参数自适应的迭代学习控制方法,以进行解耦控制并消除不确定参数的影响。通过构造Lyapunov函数和理论推导验证控制方法的稳定性。在整流器硬件平台上进行试验验证,结果表明,所设计的控制方法可有效降低电流谐波。 展开更多
关键词 中点箝位型(npc)三电平整流器 电压耦合项 迭代学习控制 谐波抑制
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基于SVPWM补偿优化的三电平NPC并网逆变器容错控制
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作者 杨清 黄景涛 关海平 《电力工程技术》 北大核心 2024年第2期199-209,共11页
为保证并网系统中三电平中点箝位(neutral point clamped,NPC)型并网逆变器单相桥臂短路或断路故障后持续运行,提出一种基于空间矢量脉宽调制(space vector pulse width modulation,SVPWM)的优化补偿型低共模电压容错控制策略。首先,通... 为保证并网系统中三电平中点箝位(neutral point clamped,NPC)型并网逆变器单相桥臂短路或断路故障后持续运行,提出一种基于空间矢量脉宽调制(space vector pulse width modulation,SVPWM)的优化补偿型低共模电压容错控制策略。首先,通过分析故障后八开关三相逆变器(eight switch three phase inverters,ESTPI)拓扑开关状态对应的共模电压大小,确定参考电压矢量合成规则;然后,通过一个基波周期内中点电流情况分析中点电位波动机理,进而对空间矢量合成进行调节补偿;最后,设计低通滤波器和滞环控制器进一步对补偿进行优化调整,保证并网电流质量的同时有效抑制了直流母线中点电位偏移。仿真结果表明,该容错控制策略能够实现三电平NPC并网逆变器单相桥臂故障后并网系统的稳定可靠运行,每个基波周期有三分之一时间的共模电压得到改善,优化补偿后的并网电流质量显著提高,且在并网电流突变时具备良好的控制特性。 展开更多
关键词 三电平逆变器 中点箝位(npc) 容错控制 中点电位波动 空间矢量脉宽调制(SVPWM)优化补偿 滞环控制器
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Role of lipids in the control of autophagy and primary cilium signaling in neurons
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作者 María Paz Hernández-Cáceres Daniela Pinto-Nuñez +5 位作者 Patricia Rivera Paulina Burgos Francisco Díaz-Castro Alfredo Criollo Maria Jose Yañez Eugenia Morselli 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期264-271,共8页
The brain is,after the adipose tissue,the organ with the greatest amount of lipids and diversity in their composition in the human body.In neurons,lipids are involved in signaling pathways controlling autophagy,a lyso... The brain is,after the adipose tissue,the organ with the greatest amount of lipids and diversity in their composition in the human body.In neurons,lipids are involved in signaling pathways controlling autophagy,a lysosome-dependent catabolic process essential for the maintenance of neuronal homeostasis and the function of the primary cilium,a cellular antenna that acts as a communication hub that transfers extracellular signals into intracellular responses required for neurogenesis and brain development.A crosstalk between primary cilia and autophagy has been established;however,its role in the control of neuronal activity and homeostasis is barely known.In this review,we briefly discuss the current knowledge regarding the role of autophagy and the primary cilium in neurons.Then we review the recent literature about specific lipid subclasses in the regulation of autophagy,in the control of primary cilium structure and its dependent cellular signaling in physiological and pathological conditions,specifically focusing on neurons,an area of research that could have major implications in neurodevelopment,energy homeostasis,and neurodegeneration. 展开更多
关键词 autophagic flux CHOLESTEROL fatty acids GPCR lysosomal storage diseases NEURONS npc1 PHOSPHOINOSITIDES primary cilium
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NPC型直挂储能变流器桥臂断路故障下低电压穿越的容错控制
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作者 孙鹏 赵晋斌 +2 位作者 潘超 毛玲 屈克庆 《南方电网技术》 CSCD 北大核心 2024年第3期93-103,共11页
NPC型直挂储能变流器长期运行可能发生桥臂断路故障造成设备停运以及影响低电压故障穿越,基于故障相与直流母线中点直连构成虚拟桥臂重构容错故障拓扑,提出了基于模型预测控制的桥臂容错低电压穿越控制策略。考虑重构后的容错拓扑结构... NPC型直挂储能变流器长期运行可能发生桥臂断路故障造成设备停运以及影响低电压故障穿越,基于故障相与直流母线中点直连构成虚拟桥臂重构容错故障拓扑,提出了基于模型预测控制的桥臂容错低电压穿越控制策略。考虑重构后的容错拓扑结构降低了直流侧电压的利用率,研究分析了该容错结构进行低压穿越的最大输出电流整定方法。由于低电压穿越过程中电压跌落后的容错拓扑输出特性发生改变,对储能直挂容错结构的输出电流、电压进行模型预测矢量分析,推导出电压跌落与最大输出电流的关系式。在重构的空间电压矢量内选择能够支撑低电压穿越的矢量状态,控制储能变流器按照低电压穿越技术规范进行有功无功功率分配,支撑电网电压。仿真结果验证了所提出的控制策略保证容错拓扑结构可以在桥臂故障期间运行的有效性以及低电压穿越过程中提供无功功率支撑的可靠性。 展开更多
关键词 低电压穿越 模型预测控制 容错控制 三电平npc 储能变流器
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Treatment with β-sitosterol ameliorates the effects of cerebral ischemia/reperfusion injury by suppressing cholesterol overload, endoplasmic reticulum stress, and apoptosis
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作者 Xiuling Tang Tao Yan +8 位作者 Saiying Wang Qingqing Liu Qi Yang Yongqiang Zhang Yujiao Li Yumei Wu Shuibing Liu Yulong Ma Le Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期642-649,共8页
β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unkno... β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways. 展开更多
关键词 APOPTOSIS blood-brain barrier Β-SITOSTEROL cerebral ischemia/reperfusion injury cholesterol overload cholesterol transport endoplasmic reticulum stress ischemic stroke molecular docking npc1L1
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NPC三电平虚拟同步机桥臂故障容错模型预测控制
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作者 金楠 肖晗 +1 位作者 谢欢 武洁 《电源学报》 CSCD 北大核心 2024年第2期147-157,共11页
虚拟同步机VSG(virtual synchronous generator)通过模拟同步机特性为新能源并网提供惯性和阻尼。然而,电力电子开关器件高频开关过程中可能会发生断路故障,导致输出电流波形严重畸变,影响电网安全稳定运行。针对中点箝位型NPC(neutral ... 虚拟同步机VSG(virtual synchronous generator)通过模拟同步机特性为新能源并网提供惯性和阻尼。然而,电力电子开关器件高频开关过程中可能会发生断路故障,导致输出电流波形严重畸变,影响电网安全稳定运行。针对中点箝位型NPC(neutral point clamped)三电平VSG桥臂故障问题,提出一种中点电压均衡的VSG容错模型预测控制策略。分析NPC三电平VSG单相桥臂故障后运行机理,在开关器件故障后利用直流侧电容组成虚拟桥臂,重构为VSG桥臂故障容错结构。建立故障情况下预测电流模型,重构故障状态空间电压矢量,将直流侧中点电容电压引入容错模型代价函数,减小电容电压波动,实现VSG桥臂故障容错运行。实验结果表明,在开关器件发生故障后,NPC三电平VSG能容错连续运行,验证了所提模型预测容错控制策略的有效性,提高了VSG运行可靠性。 展开更多
关键词 虚拟同步机 容错模型 模型预测控制 中点钳位型变换器 代价函数
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代入、演绎、黏合:作为沉浸式文旅景观的真人NPC
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作者 占琦 《新闻知识》 2023年第5期67-73,95,共8页
沉浸式文旅的风靡,使真人NPC作为一种新兴职业进入大众视野。从游客到玩家,从凝视到参与,从观赏到互动,沉浸式文旅体验中,真人NPC通过符号表征建构自我身份,既是文旅游戏的“摆渡人”,又是体验互动的“掌控者”,全知视角固化其角色地位... 沉浸式文旅的风靡,使真人NPC作为一种新兴职业进入大众视野。从游客到玩家,从凝视到参与,从观赏到互动,沉浸式文旅体验中,真人NPC通过符号表征建构自我身份,既是文旅游戏的“摆渡人”,又是体验互动的“掌控者”,全知视角固化其角色地位和玩家认同。真人NPC通过符号包装重塑文旅场景,全感官包裹增强现实性的“真”,开放叙事再造合法性的“善”,深度互动营造戏剧性的“美”,全感官演绎场景维度。通过符号消费生产文旅价值,耦合游戏空间、文化空间和消费空间,黏合玩家对文旅场景的集体记忆和文化认同,促进空间消费。真人NPC已作为沉浸式文旅景观存在,但“工具人”“舒适物”“消费品”的刻板印象,易使其在符号消费和过度营销中迷失自我,从而导致情感耗竭。 展开更多
关键词 沉浸文旅 真人npc 剧本杀 文化消费
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基于NPC三电平的永磁同步电机控制研究 被引量:1
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作者 刘嘉庆 姜建国 《大电机技术》 2023年第5期25-31,37,共8页
基于NPC(neutral point clamped,中点钳位型)三电平逆变器的永磁同步电机(permanent magnet synchronous motor, PMSM)的矢量控制系统中,传统的直角坐标系SVPWM算法三角函数计算量大,系统计算时间长,软件程序复杂,而且存在中点电位不平... 基于NPC(neutral point clamped,中点钳位型)三电平逆变器的永磁同步电机(permanent magnet synchronous motor, PMSM)的矢量控制系统中,传统的直角坐标系SVPWM算法三角函数计算量大,系统计算时间长,软件程序复杂,而且存在中点电位不平衡的问题,影响电流、电机转速和转矩。本文构建了以基于gh坐标系的NPC三电平逆变器为核心的PMSM矢量控制系统,提出了一种基于电荷预测的中点电位平衡调节控制方案,并搭建了PMSM控制系统的仿真模型和实验平台,通过仿真和实验对控制系统进行了检验,结果表明使用该方法的PMSM运行情况良好,具有较好的实用性。 展开更多
关键词 npc三电平 永磁同步电机 SVPWM算法 中点电位
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基于矩形区域分类的NPC型H桥级联五电平逆变器简化模型预测电压控制
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作者 袁庆庆 燕磊 +1 位作者 杨丰年 涂谦 《中国电机工程学报》 EI CSCD 北大核心 2023年第12期4758-4768,共11页
为进一步提高中点电压钳制(neutral point clamped,NPC)H桥级联五电平逆变器的动态响应、降低控制器计算负担的同时确保装置低损耗运行,文中在电压矢量矩形区域分类的基础上,提出一种以满足动态响应和降低开关损耗为目标的两级优化模型... 为进一步提高中点电压钳制(neutral point clamped,NPC)H桥级联五电平逆变器的动态响应、降低控制器计算负担的同时确保装置低损耗运行,文中在电压矢量矩形区域分类的基础上,提出一种以满足动态响应和降低开关损耗为目标的两级优化模型预测电压控制策略。首先根据逆变器数学模型和期望电流进行目标电压矢量计算、修正,接着基于矩形区域分类对目标电压矢量进行定位;并以定位后的候选矢量为基础,设计了两级优化目标函数以输出满足要求的最优矢量。仿真和实验结果验证了该方法的有效性,与空间矢量脉宽调制以及传统模型预测电流、电压控制策略相比,该文所研究的两级优化模型预测电压控制策略,在确保逆变器动态响应的前提下既能降低控制器计算负担,还能有效减少器件开关损耗。 展开更多
关键词 中点电压钳制型H桥级联五电平逆变器 矩形区域分类 模型预测电压控制 两级优化 低开关损耗
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Mr.Zhou Tienong,Vice-Chairman of NPC Standing Committee and President of CAFIU visited Europe from July 2 to 13,2011. 被引量:13
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《International Understanding》 2011年第4期F0002-F0002,1-5,共6页
关键词 npc
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Estimation of Aqueous Solubility (-lgS_w) of All Polychlorinated Biphenyl (PCB) Congeners by Density Functional Theory and Position of Cl Substitution (NPCS) Method 被引量:3
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作者 WEI Xiao-Yan GE Zhi-Gang WANG Zun-Yao XU Jiao 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第5期519-528,共10页
Optimization calculations of 209 polychlorinated biphenyls (PCBs) were carried out at the B3LYP/6-31G* level. It was found that there is significant correlation between the Cl substitution position and some structural... Optimization calculations of 209 polychlorinated biphenyls (PCBs) were carried out at the B3LYP/6-31G* level. It was found that there is significant correlation between the Cl substitution position and some structural parameters. Consequently, Cl substitution positions were taken as theoretical descriptors to establish a novel QSPR model for predicting –lgS_w of all PCB congeners. The model achieved in this work contains four variables, of which r2 = 0.9527, q2 = 0.9490 and SD = 0.25 with large t values. In addition, the variation inflation factors (VIFs) of variables in this model are all less than 5.0, suggesting high accuracy of the –lgS_w predicting model. And the results of cross-validation test and method validation also show that the model exhibits optimum stability and better predictive capability than that from the AM1 method. 展开更多
关键词 多氯联苯同源物 水溶液溶解度 估计 密度函数理论 氯取代位法
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2012 CPPCC & NPC:“Speed Down,Quality Up”——It’s Time for Deepening Reform
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作者 Guo Yan 《China's Foreign Trade》 2012年第4期18-18,共1页
"It’s time for deepening the reform,and we will keep forging ahead resolutely",spokesman Zhao Qizheng made this remark as the prelude to 2012 CPPCC & NPC on the first press conference of the Fifth
关键词 DEEPENING ahead REMARK FORGING FISCAL cppcc npc ex
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传统发酵肉源乳酸菌介导NPC1L1、ABCG5/G8基因表达对胆固醇代谢的影响
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作者 曹凯慧 张开屏 +4 位作者 马俊杰 程峰 杨雪倩 田建军 靳烨 《中国食品学报》 EI CAS CSCD 北大核心 2023年第5期96-104,共9页
过高的胆固醇摄入可能会导致机体心脑血管出现健康问题。通过乳酸菌可以调控小肠中胆固醇代谢相关基因的表达,调节机体内胆固醇的吸收代谢,从而影响体内胆固醇含量。对15株传统发酵肉制品中分离筛选的乳酸菌进行体外降胆固醇能力和耐酸... 过高的胆固醇摄入可能会导致机体心脑血管出现健康问题。通过乳酸菌可以调控小肠中胆固醇代谢相关基因的表达,调节机体内胆固醇的吸收代谢,从而影响体内胆固醇含量。对15株传统发酵肉制品中分离筛选的乳酸菌进行体外降胆固醇能力和耐酸耐胆盐能力筛选,将筛选到的乳酸菌用于动物实验。结果表明,15株乳酸菌中有4株乳酸菌(CM6、CM9、CM28、CM42)具有良好的体外降胆固醇能力,平均降解率为52.92%。对它们进行耐酸和耐胆盐试验,在pH 2和0.3%胆盐添加量的条件下菌株CM6活菌数达到106 CFU/mL,选择CM6进行后续动物实验。乳酸菌灌胃小鼠30 d后,乳酸菌组小鼠血清中总胆固醇含量和甘油三酯含量乳显著低于对照组(P<0.05);乳酸菌组小鼠小肠中NPC1L1基因相对表达量显著低于对照组(P<0.05),ABCG5/G8基因表达量显著高于对照组(P<0.05)结论:乳酸菌CM6具有调控胆固醇代谢相关基因表达的能力,从而降低体内胆固醇含量。 展开更多
关键词 乳酸菌 胆固醇 npc1L1 ABCG5/G8 基因相对表达量
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Design and Implementation of a Three-Phase Active T-Type NPC Inverter for Low-Voltage Microgrids
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作者 Rick Chen Ying-Yu Tzou 《Energy and Power Engineering》 2017年第4期70-77,共8页
This paper presents the design and implementation of a 3 kVA three-phase active T-type neutral-point clamped (NPC) inverter with GaN power devices for low-voltage microgrids. The designed inverter is used in a battery... This paper presents the design and implementation of a 3 kVA three-phase active T-type neutral-point clamped (NPC) inverter with GaN power devices for low-voltage microgrids. The designed inverter is used in a battery-based energy system (BESS) for power conversion optimization in applications to low-voltage microgrids. A modular design method has been developed for the design and implementation of the AT-NPC inverter. Experimental verification has been carried out based on a 3-kW three-phase T-Type NPC grid-connected inverter. FPGA based digital control technique has been developed for the current control of the three-level three-phase grid inverter. A maximum efficiency of 98.49% has been achieved within a load range from 50% to 75%. 展开更多
关键词 ACTIVE T-TYPE npc Inverter Modular Design Methodology Loss Analysis Efficiency Optimization
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Ambassadors' View on NPC&CPPCC
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作者 Guo Yan 《China's Foreign Trade》 2010年第6期36-39,共4页
As the world's major economies still kept in the mires of recesssion,China realized a speedy recovery with a 8.7-percent economic growth in2009.so,although,NPC & CPPCC has closed its curtains in Beijing on Mar... As the world's major economies still kept in the mires of recesssion,China realized a speedy recovery with a 8.7-percent economic growth in2009.so,although,NPC & CPPCC has closed its curtains in Beijing on March 14,2010,we still can heard about the comments on them.During the two sessions,the world media focused their attentions on what China next steps will be implemented,and which 展开更多
关键词 全国人民代表大会 经济增长 经济建设 cppcc
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NPC & CPPCC Sessions 2016
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《China Today》 2016年第4期14-15,共2页
THE National People’s Congress(NPC)concluded its annual session on March 16,2016.The session,which convened on March 5,reviewed and approved the outline of the 13th Five-Year Plan(2016-2020)
关键词 协会 五年规划 npc
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NPC & CPPCC Sessions 2015
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《China Today》 2015年第4期14-15,共2页
The third session of the 12th National People’s Congress(NPC)began in Beijing on March 5,2015.At the opening meeting,Chinese Premier Li Keqiang delivered the government work report and gave an overview of the 2015 wo... The third session of the 12th National People’s Congress(NPC)began in Beijing on March 5,2015.At the opening meeting,Chinese Premier Li Keqiang delivered the government work report and gave an overview of the 2015 work plan.The ten-and-a-half-day session reviewed a draft amendment to the country’s Legislation Law.Lawmakers have now set the stage for an important year in China’s efforts to deepen re- 展开更多
关键词 npc 政府工作 开幕式 总理李 国务院
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