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准中性等离子体模拟中的两种渐近保持PIC算法研究 被引量:3
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作者 孙安邦 毛根旺 +4 位作者 P.Degond F.Deluzet L.Navoret M.-H.Vignal 夏广庆 《真空科学与技术学报》 EI CAS CSCD 北大核心 2010年第1期6-10,共5页
针对准中性无碰撞等离子体的Vlasov方程及与其相耦合的求解电势的Poisson方程所组成的Vlasov-Poisson系统,提出了两种渐近保持PIC算法,并将其运用到一维周期性波动等离子体模型上。与传统PIC算法相比较,两种渐近保持PIC算法解决了Vlasov... 针对准中性无碰撞等离子体的Vlasov方程及与其相耦合的求解电势的Poisson方程所组成的Vlasov-Poisson系统,提出了两种渐近保持PIC算法,并将其运用到一维周期性波动等离子体模型上。与传统PIC算法相比较,两种渐近保持PIC算法解决了Vlasov-Poisson系统多尺度参数中的小量束缚问题,时间和空间步长的选取可以克服传统粒子模型中等离子体周期及德拜长度的限制,且模拟结果稳定正确,大大提高了计算效率。 展开更多
关键词 渐近保持 Vlasov-Poisson 准中性 PIC 多尺度
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准中性锌空气电池的研究 被引量:1
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作者 陈昌国 高宇 +2 位作者 谢波 吕红 王强 《电源技术》 CAS CSCD 北大核心 2002年第4期288-290,共3页
采用循环伏安和线性电流扫描等电化学方法系统研究了NaCl、KCl、NH4Cl、(NH4) 2 SO4等电解质溶液对锌电极和空气电极电化学行为以及锌空气电池放电特性的影响。电极电势和电池电压表明NH4Cl电解质特性相对较好 ;而且添加适量KCl既有利... 采用循环伏安和线性电流扫描等电化学方法系统研究了NaCl、KCl、NH4Cl、(NH4) 2 SO4等电解质溶液对锌电极和空气电极电化学行为以及锌空气电池放电特性的影响。电极电势和电池电压表明NH4Cl电解质特性相对较好 ;而且添加适量KCl既有利于提高电池的工作电压 ,又能减小锌电极的自腐蚀 ;4mol/LNH4Cl+ 展开更多
关键词 准中性锌空气电池 电解质溶液 锌电极 空气电极 电化学法系统
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中国经济增长之谜(1978—2010):准中性政府、制度变迁与包容性发展 被引量:3
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作者 李刚 许跃辉 《华东经济管理》 CSSCI 2012年第7期49-54,共6页
30多年来中国经济高速增长现象,既不符合"华盛顿共识"标准,也无法使用主流经济学理论进行解释,被称为"中国增长之谜"。这里通过构建包含政府、市场、制度和利益集团等组织在内的分析框架,并引入准中性政府的概念,... 30多年来中国经济高速增长现象,既不符合"华盛顿共识"标准,也无法使用主流经济学理论进行解释,被称为"中国增长之谜"。这里通过构建包含政府、市场、制度和利益集团等组织在内的分析框架,并引入准中性政府的概念,可以较好地解释中国增长之谜。准中性政府是一个在短期内依据社会主要矛盾制定有偏向的政策,但是利益集团之间相对地位的变化,导致政府无法在长期内偏向某一固定集团。也就是说,准中性政府具有短期内有偏、长期内无偏的特质。这种特质构成了中国经济高速增长的内在机制,而准中性政府通过制度变迁的方式使中国经济增长获得强大的动力。但是中国经济高速增长也带来了收入差距过大、环境破坏严重等问题,采取包容性发展方式是解决这些问题的有效手段,因此,追求包容性发展也就成了准中性政府的终极目标。 展开更多
关键词 准中性政府 制度变迁 包容性发展
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锌空气电池准中性电解液的研究
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作者 于华章 周德璧 +3 位作者 罗素朴 彭业成 赵晶 梁雨南 《应用化工》 CAS CSCD 2014年第1期121-123,共3页
研究了锌空气电池中性、准中性电解液的主要成分,采用线性扫描伏安法考察了NH4Cl、ZnCl2、KCl及它们的混合溶液对锌电极电化学性能的影响,并组装电池恒流放电测试。结果表明,对于低电流密度放电要求的准中性锌空气电池采用NH4Cl作为主... 研究了锌空气电池中性、准中性电解液的主要成分,采用线性扫描伏安法考察了NH4Cl、ZnCl2、KCl及它们的混合溶液对锌电极电化学性能的影响,并组装电池恒流放电测试。结果表明,对于低电流密度放电要求的准中性锌空气电池采用NH4Cl作为主体电解质的锌电极性能相对较好;在NH4Cl溶液中添加KCl,有利于改善溶液导电性,提高放电电压和延长放电时间。最佳溶液配比为4 mol/L NH4Cl+2 mol/L KCl。 展开更多
关键词 锌电极 准中性 锌空气电池 电解液
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Zn(Ⅱ)在锌电极上的电沉积机理 被引量:5
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作者 徐双全 刘春侠 +3 位作者 沈庆峰 张涛 倪源 俞小花 《无机化学学报》 SCIE CAS CSCD 北大核心 2016年第3期386-392,共7页
在Zn(Ⅱ)-NH_4Cl准中性体系中,采用循环伏安法(CV)研究了Zn^(2+)在锌电极上的反应方式,通过计时电流法(CA)研究了Zn^(2+)沉积的成核方式,利用交流阻抗谱(EIS)考察了不同过电位时Zn^(2+)沉积的阻抗行为。结果表明:Zn^(2+)的电沉积是一个... 在Zn(Ⅱ)-NH_4Cl准中性体系中,采用循环伏安法(CV)研究了Zn^(2+)在锌电极上的反应方式,通过计时电流法(CA)研究了Zn^(2+)沉积的成核方式,利用交流阻抗谱(EIS)考察了不同过电位时Zn^(2+)沉积的阻抗行为。结果表明:Zn^(2+)的电沉积是一个不可逆电极反应,以两步骤单电子串联的方式进行,第一步为速控步;电极反应的电荷传递系数与锌电极的表面结构有关。在恒电位条件下,体系中锌电极上Zn^(2+)的结晶近似于三维瞬时成核方式。Zn^(2+)的沉积经历了覆盖、吸附成膜、大量晶核形成等过程,该过程随着控制电位的负移由电化学极化过渡到电化学极化-浓差极化混合控制阶段。最后给出了Zn^(2+)在锌电极上电沉积过程的机理。 展开更多
关键词 Zn(Ⅱ)-NH4Cl准中性体系 电沉积 循环伏安 计时电流 交流阻抗谱
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霍尔推力器不同壁面侵蚀对低频振荡特性影响研究 被引量:1
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作者 韩轲 汪颖 鲁海峰 《推进技术》 EI CAS CSCD 北大核心 2020年第6期1434-1440,共7页
基于霍尔推力器一维准中性流体模型,对放电壁面侵蚀对低频振荡特性的影响进行了数值模拟研究。通过改变霍尔推力器放电通道的横截面积,研究了霍尔推力器寿命期内通道受离子溅射后,放电电流振荡特性变化。研究结果显示,横截面积从25cm2... 基于霍尔推力器一维准中性流体模型,对放电壁面侵蚀对低频振荡特性的影响进行了数值模拟研究。通过改变霍尔推力器放电通道的横截面积,研究了霍尔推力器寿命期内通道受离子溅射后,放电电流振荡特性变化。研究结果显示,横截面积从25cm2增大到37cm2时,放电电流振荡幅值增加,振荡频率基本不变;继续增加横截面积,放电电流振荡幅值减小,振荡频率增加。理论分析表明:通道侵蚀面积增大,导致离子碰撞频率变化,进而引起振荡特性变化。 展开更多
关键词 霍尔推力器 横截面积 低频振荡 壁面侵蚀 一维准中性流体模型
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政府监管证券市场的伦理模式及其转换路径
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作者 黎元奎 《改革》 CSSCI 北大核心 2006年第8期102-106,共5页
经济伦理与市场经济的发展存在互动关系。证券市场政府监管制度具有“制度”和“伦理”的双重属性。从经济伦理学视角来看,政府证券监管在价值取向上分为中性监管、准中性监管和自利监管三种伦理模式。10多年来,我国证券市场政府监管... 经济伦理与市场经济的发展存在互动关系。证券市场政府监管制度具有“制度”和“伦理”的双重属性。从经济伦理学视角来看,政府证券监管在价值取向上分为中性监管、准中性监管和自利监管三种伦理模式。10多年来,我国证券市场政府监管的伦理模式为自利监管。由自利监管向准中性监管转换,是我国证券市场政府监管伦理模式必然的选择路径。 展开更多
关键词 经济伦理价值 中性监管 准中性监管 自利监管
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非平衡态Ti-H等离子体发射光谱的双温度诊断研究 被引量:1
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作者 邓春凤 卢彪 +2 位作者 伍春雷 汪一夫 温中伟 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第12期3374-3379,共6页
单次脉冲工作的真空弧离子源,采用金属钛吸附氢形成的Ti-H固溶体作阴极,生成的等离子体同时包含金属钛和氢的成分,且在径向、横向以及时间尺度上都存在梯度,整个体系处于非平衡状态,不能用一个统一的温度来描述。假设由电子组成的子系... 单次脉冲工作的真空弧离子源,采用金属钛吸附氢形成的Ti-H固溶体作阴极,生成的等离子体同时包含金属钛和氢的成分,且在径向、横向以及时间尺度上都存在梯度,整个体系处于非平衡状态,不能用一个统一的温度来描述。假设由电子组成的子系统和由其他重粒子组成的子系统分别达到平衡,即Ti-H等离子体由电子温度和重粒子温度两个温度来描述,为双温度等离子体。采用Culdberg-Waage解离方程和Saha电离方程分别对系统中的分子解离和原子电离过程进行描述,结合等离子体电荷准中性条件,同时引入原子发射光谱这一无干扰的等离子体诊断方法,对Ti-H等离子体的温度和粒子数密度进行诊断。在MATLAB环境下,同时考虑金属Ti原子和一价Ti离子的电离,计算结果显示:根据谱线的斯塔克展宽确定的电子密度进行计算,除重粒子温度和氢气分子的数密度之外,其他的参数均可得到较准确的诊断结果;电子密度数值的准确性对计算结果有很大的影响;如果能够在计算之前确定重粒子温度,则可对Ti-H等离子体的温度和粒子数密度进行准确的定量分析。 展开更多
关键词 双温度 发射光谱 Culdberg-Waage解离方程 Saha电离方程 中性
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等离子体概念、分类及基本特性 被引量:8
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作者 王利娟 《宜宾学院学报》 2009年第6期41-43,共3页
通过讨论等离子体的概念及其分类,并给出关于等离子体特性的时空判据.
关键词 等离子体 中性 德拜半径
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改性酚醛保温板研究与应用 被引量:2
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作者 康素梅 刘占清 +10 位作者 袁颖涛 樊武琨 赵月娇 田壮 尉蔚 冯春妍 王宇 李娜 温婷 范立瑛 于原 《中国建材科技》 CAS 2021年第1期42-43,共2页
酚醛泡沫以甲阶酚醛树脂为主要原料,由于其优异的保温和阻燃性能在保温领域具有广阔的应用前景。但是,酚醛泡沫在成型过程中通过酸性(催化)固化剂固化成型,金属材料与泡沫体接触时容易受到腐蚀。为了降低金属被腐蚀的可能性,在不影响酚... 酚醛泡沫以甲阶酚醛树脂为主要原料,由于其优异的保温和阻燃性能在保温领域具有广阔的应用前景。但是,酚醛泡沫在成型过程中通过酸性(催化)固化剂固化成型,金属材料与泡沫体接触时容易受到腐蚀。为了降低金属被腐蚀的可能性,在不影响酚醛泡沫其他优良性能的前提下,通过选择合适的碱性填料、用酯固化作用取代酸固化剂、合成吸酸剂等方法降低酚醛泡沫的酸性。 展开更多
关键词 酚醛泡沫 准中性 碱性填料 复合酸固化剂
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等离子体的准电中性
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作者 尹国盛 李卓 张果义 《广西物理》 2002年第2期4-6,共3页
讨论了等离子体的准电中性 ,并给出了关于准电中性等离子体的时空判据。
关键词 等离子体 中性 德拜半径 等离子体频率
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Asymptotic Behavior of Global Smooth Solution of 1-D Quasineutral Drift Diffusion Model for Semiconductors
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作者 CHEN Shou-xin HAN Xiao-sen 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第3期385-396,共12页
In this paper, we study the asymptotic behavior of globally smooth solutions of initial boundary value problem for 1-d quasineutral drift-diffusion model for semiconductors. We prove that the smooth solutions(close t... In this paper, we study the asymptotic behavior of globally smooth solutions of initial boundary value problem for 1-d quasineutral drift-diffusion model for semiconductors. We prove that the smooth solutions(close to equilibrium)of the problem converge to the unique stationary solution. 展开更多
关键词 quasineutral drift-diffusion model global existence and uniqueness asymptotic behavior
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Influence of Mechanical Grinding on the Interface Characteristics of Rice/Wheat Straws
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作者 Dingguo Zhou Peixing Wei 《Journal of Agricultural Science and Technology(B)》 2013年第5期369-376,共8页
The mechanical grinding method was used to make rice and wheat straw flakes and the properties of the interface of straws before and after grinding were evaluated. The particle boards were prepared using two kinds of ... The mechanical grinding method was used to make rice and wheat straw flakes and the properties of the interface of straws before and after grinding were evaluated. The particle boards were prepared using two kinds of straw flakes, respectively and their physical and mechanical properties were investigated. The results showed that the rice straw was easier to be broken when compared with wheat straw and the inner surface of cells in grinded straws was exposed remarkably. The characteristic peaks of lignin and cellulose on the surface of wheat straw were more significant than rice straw. The free-radical concentrations of straws were increased dramatically after being grinded with heating in the range from I00 ~C to 200 ~C. The surface free energy of straws was also improved after being grinded and the value in wheat straw was higher than that of rice straw, which implies that wheat straw was easier to be bonded than rice straw. The physical and mechanical properties of two kinds of straw particle boards could achieve the requirements of Chinese National Standards of GB 4897.3-2003, while wheat straw particle boards had better properties than those made from rice straws. 展开更多
关键词 Rice straw wheat straw surface free radicals surface free energy mechanical grinding method.
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Quality control of ultrasonic measurement of carotid artery intima-media thickness 被引量:2
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作者 Ying Yang Feng Zhao +4 位作者 Li-Tong Qi Bao-Wei Zhang Feng Chen Sai-Nan Zhu Yong Huo 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2009年第4期222-226,共5页
Background To report quality control methods and baseline reproducibility data of the ultrasound measurements of carotid artery intima-media thickness in the project of Establishment of an Integrated System for Corona... Background To report quality control methods and baseline reproducibility data of the ultrasound measurements of carotid artery intima-media thickness in the project of Establishment of an Integrated System for Coronary Heart Disease Prevention and Treatment. Methods Standard ultrasound scanning and measuring protocols were established by the study group. All sonographers and readers were trained by the carotid ultrasound core lab and all digital ultrasound images were centrally read. Ten subjects were scanned twice (with 1 week interval) by 2 sonographers independently and images were read by a single reader to evaluate the sonographer variability. Twenty subjects' images were read twice (with 1 week interval) by a single reader to assess the reader variability and the reproducibility of IMT measured at different carotid segments. Results The intraclass correlation (ICC) of intra- and inter-sonographer and intra- reader for mean IMT measurements was 0.99, 0.98 and 0.97 respectively; while for max IMT, it was 0.97, 0.99 and 0.95 respectively. Among different carotid segments and sites, ICC for mean 1MT measurements of common carotid (CCA), carotid artery bulb (Bulb), internal carotid artery (ICA), overall near wall and overall far wall was 0.97, 0.99, 0.89, 0.93 and 0.98 respectively. Conclusion The reproducibility of IMT measurements according to our protocol is acceptable, although better reproducibility is found when measuring the mean IMT than max IMT, CCA and Bulb IMT than ICA IMT, and far wall IMT than near wall IMT. 展开更多
关键词 ATHEROSCLEROSIS carotid arteries ULTRASOUND REPRODUCIBILITY intima-media thickness
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Precision Treatment of Primary Liver Cancer with Traditional Chinese Medicine
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作者 Wu Xiaoxiong Zhu Shijie Chen Tingsong 《World Journal of Integrated Traditional and Western Medicine》 2017年第4期14-14,共1页
The precision treatment of liver cancer in TCM belongs to macroscopic precision treatment. Precision treatment uses minimal medical resources to maximize medical outcomes. At present, there is no precision treatment s... The precision treatment of liver cancer in TCM belongs to macroscopic precision treatment. Precision treatment uses minimal medical resources to maximize medical outcomes. At present, there is no precision treatment system of TCM for liver cancer. In clinical, we summed up the precision treatment route of TCM for liver cancer: TCM and Western medicine axe closely integrated, and the dialectical content fits perfectly with nature of disease, accurate correspondence between the treatment method and the syndrome type, the nature of drug and human body nature are just "neutralizing". Make good quality control in these four aspects. Any big deviation in any aspect will affect the curative effects. 展开更多
关键词 Primary liver cancer TCM Precision treatment
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Precision Treatment of Primary Liver Cancer with Traditional Chinese Medicine
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作者 Wu Xiaoxiong Zhu Shijie and Chen Tingsong 《World Journal of Integrated Traditional and Western Medicine》 2017年第3期16-16,共1页
The precision treatment of liver cancer in TCM belongs to macroscopic precision treatment. Precision treatment uses minimal medical resources to maximize medical outcomes. At present, there is no precision treatment s... The precision treatment of liver cancer in TCM belongs to macroscopic precision treatment. Precision treatment uses minimal medical resources to maximize medical outcomes. At present, there is no precision treatment system of TCM for liver cancer. In clinical, we summed up the precision treatment route of TCM for liver cancer: TCM and Western medicine are closely integrated, and the dialectical content fits perfectly with nature of disease, accurate correspondence between the treatment method and the syndrome type, the nature of drug and human body nature are just "neutralizing". 展开更多
关键词 Primary liver cancer TCM Precision treatment
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Comparison of Minimum Energy Performance Standards (MEPS) Programs in the USA and China
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作者 杨泽世 《China Standardization》 2013年第1期74-79,共6页
Abstract: Nowadays energy saving and environmental protection are crucial issues in the international society. One of the best solutions for both issues is to improve energy efficiency. To improve energy efficiency, ... Abstract: Nowadays energy saving and environmental protection are crucial issues in the international society. One of the best solutions for both issues is to improve energy efficiency. To improve energy efficiency, it is commonly recognized by both standards and energy sectors that Minimum Energy Performance Standards (MEPS) could play an important role . China and the USA, the top two energy consumption countries in the world, both have adopted MEPS program to address the problem of energy conservation and environmental protection. This paper analyzes and compares the two countries' MEPS programs from a historical and legal context, examining the role of different stakeholders in the process,the process, the outcomes by standards,and then makes some recommendations for both sides. 展开更多
关键词 MEPS COMPARISON USA China
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Research on the Evaluation System of National Standardization
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作者 Yang Feng Wang Jinyu 《China Standardization》 2010年第4期33-41,共9页
Standardization receives varied attention in different countries. Based on the Chinese national standardization status, this paper sets an evaluation system of national standardization on the principles of logic, comp... Standardization receives varied attention in different countries. Based on the Chinese national standardization status, this paper sets an evaluation system of national standardization on the principles of logic, comprehensiveness and operability, taking into account national standards and standardization activities. The evaluation system evaluates the national standardization development level through four aspects: standard development, standards implementation, standardization supporting measures, and participation in international standardization. This evaluation system provides a reasonable basis to evaluate the national standardization development level. The survey shows that if China wants to enhance its standardization development level, China needs to improve its standard development level, strengthen implication and application of standards, expand the standardization support measures and continuously improve the level of participation in international standardization. 展开更多
关键词 China STANDARDIZATION EVALUATION
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Analyzing the Impacts of Minimum Wage Standards on Reducing the Working Poor in China
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作者 Yongjian Hu 《Sociology Study》 2014年第7期573-580,共8页
During the past decades, the transformation of the labor market has significantly impacted on workers' wage structures and their employment in China. Along with the widening wage gaps and the growing income inequalit... During the past decades, the transformation of the labor market has significantly impacted on workers' wage structures and their employment in China. Along with the widening wage gaps and the growing income inequalities, the size of non-standard jobs expanded rapidly in China's urban labor market. As a result of this, the concept of working poor has become increasingly applicable to social and labor market realities in China, Based on the household survey data and by using quantitative analysis, this paper attempts to examine the interaction between the compulsory minimum wage standards and the working poor in the period of China's economic transition. The results show that for those whose monthly wages higher than the compulsory minimum wage standards were less likely to work poor and that workers with wages lower than the minimum wage floor were vulnerable to working poor, which supported the expectation that the implementation of compulsory minimum wages would help to reduce the risk of being a member among the working poor in China's urban labor market. 展开更多
关键词 Working poor minimum wage standards wage gaps logit model
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Characteristics and Development Modes of Standardization forChina's National High-Tech Zones:A Review
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作者 郑巧英 田川 徐成华 《China Standardization》 2012年第2期52-57,共6页
Indigenous innovation focused on the development of technical standards has become the core of China's innovation policy,since China released the "Outline of the National Program for Longand Medium-Term Scien... Indigenous innovation focused on the development of technical standards has become the core of China's innovation policy,since China released the "Outline of the National Program for Longand Medium-Term Scientific and Technological Development (2006-2020)" in 2006.Meanwhile,standardization issues are greatly emphasized by high-tech zones which serve as the major carriers of national economic growth as well as innovation clusters in the context of fast-growing international standardization.By means of the effective guide of the government,the standardization of high-tech zones in China now presents a wide range of operating modes.Specifically,they can be divided predominantly into the government promotion mode,the alliance collaboration mode,the research-standard-industry linkage mode,and the talent training mode,in terms of the main body of work and influence factors. 展开更多
关键词 National High-Tech Zone STANDARDIZATION standard development modes
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