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Empirical Study on Standardization Curricula in Chinese Universities 被引量:1
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作者 Zhao Chaoyi Pang Zhenghu 《China Standardization》 2010年第1期11-14,共4页
This paper summarizes partial findings on education about standardization by CNIS in 2008. As of December 31, 2008, 21 universities and colleges in China had established a standardization curriculum. This paper deals ... This paper summarizes partial findings on education about standardization by CNIS in 2008. As of December 31, 2008, 21 universities and colleges in China had established a standardization curriculum. This paper deals with standardization education related to economic management, engineering, agriculture and science of law and summarizes respondents' opinions on teaching performances and design of teaching materials and curriculums. 展开更多
关键词 empirical study EDUCATION standardization and curriculum
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Dual-Material Electron Beam Selective Melting:Hardware Development and Validation Studies 被引量:12
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作者 Chao Guo Wenjun Ge Feng Lin 《Engineering》 SCIE EI 2015年第1期124-130,共7页
Electron beam selective melting (EBSM) is an additive manufacturing technique that directly fabricates three-dimensional parts in a layerwise fashion by using an electron beam to scan and melt metal powder. In recen... Electron beam selective melting (EBSM) is an additive manufacturing technique that directly fabricates three-dimensional parts in a layerwise fashion by using an electron beam to scan and melt metal powder. In recent years, EBSM has been successfully used in the additive manufacturing of a variety of materials. Previous research focused on the EBSM process of a single material. In this study, a novel EBSM process capable of building a gradient structure with dual metal materials was developed, and a powder-supplying method based on vibration was put forward. Two different powders can be supplied individually and then mixed. Two materials were used in this study: Ti6AI4V powder and Ti47AI2Cr2Nb powder. Ti6AI4V has excellent strength and plasticity at room temperature, while Ti47AI2Cr2Nb has excellent performance at high temperature, but is very brittle. A Ti6AI4V/Ti47AI2Cr2Nb gradient material was successfully fabricated by the developed system. The microstructures and chemical compositions were characterized by optical microscopy, scanning microscopy, and electron microprobe analysis. Results showed that the interface thickness was about 300 μm. The interface was free of cracks, and the chemical compositions exhibited a staircase-like change within the interface. 展开更多
关键词 additive manufacturing electron beam selectivemelting gradient materials titanium alloy TiAI alloy
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Structural Decomposition Analysis on Energy Intensity Changes at Regional Level 被引量:1
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作者 廖华 王策 +1 位作者 朱治双 马晓微 《Transactions of Tianjin University》 EI CAS 2013年第4期287-292,共6页
As China's energy intensity fluctuated in recent years, it is necessary to examine whether this fluctuation happened at a regional level. This paper establishes a decomposition model by using the structural decomp... As China's energy intensity fluctuated in recent years, it is necessary to examine whether this fluctuation happened at a regional level. This paper establishes a decomposition model by using the structural decomposition analysis (SDA) method at a regional level. Then this model is employed to empirically analyze the changes of Beijing's energy intensity. The conclusions are as follows: during 2002-2010, except petroleum, the energy intensity decreased and the changes were mostly attributed to the technology changes, while the final use variation actually increased the energy intensity; comparing different periods of 2002-2010, the decline rates of energy intensity for coal and hydropower were decreasing, resulting from the production technology being more energy-intensive than before; the energy intensity changes of petroleum firstly increased substantially and then decreased moderately. 展开更多
关键词 structural decomposition analysis input-output analysis energy intensity
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Performance Analysis of a Woodchip Downdraft Gasifier: Numerical Prediction and Experimental Validation
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作者 Emanuela Manzino Daniela Olampi Ferruccio Pittaluga 《Journal of Energy and Power Engineering》 2015年第4期336-347,共12页
The study deals with a multi-faceted theoretical approach, symbolic, analytical and numerical, based on the chemical equilibrium assumption, addressed at predicting the performance trends of downdrafi wood-gasificatio... The study deals with a multi-faceted theoretical approach, symbolic, analytical and numerical, based on the chemical equilibrium assumption, addressed at predicting the performance trends of downdrafi wood-gasification processes so to assess the optimal ranges of input parameters, in particular the equivalence ratios, suitable to achieving the highest cold gas efficiencies whilst keeping the more the possible tar-free the produced bio-syngas. The time-steady, zero-dimensional model has been developed within MATLAB (the computing language and interactive environment from Matrix Laboratory) and solved by enforcing the constraints posed by the equilibrium constants in relation to two reactions, gas-water shift and methanation. Particular care is devoted toward verifying the real attainment of the equilibrium condition, as attested by an actual presence of products from the equilibrium reactions together with a zero difference AE between the energy flows entering and exiting the system, an issue often overlooked. With respect to other similar theoretical approaches, the numerical model, assisted by the symbolic counterpart for better interpretation and intrinsic validation of results, shows a distinct advantage in predicting rather accurately the syngas composition for varying gasification temperatures, as attested by cross comparisons with experimental data directly taken on an instrumented, dedicated, small-scale downdraft gasifier operational at DIME/SCL (the Savona Combustion Laboratory of DIME, the Dept. of Mechanical, Energy, Management and Transportation Engineering of Genova University). The behavior of cold gas efficiency clearly points out that, from an energy conversion point of view, the optimal gasification temperatures turn out comprised between 900 ℃ and 1,000 ℃: this range is indeed characterized by the highest concentrations in the energy-rich syngas components CO and H2. For higher temperatures, as induced by higher air-to-fuel ratios, the progressive oxidation of above components, together with increasing nitrogen levels, would decrease the bio-syngas heat values. 展开更多
关键词 Downdraft gasifier woodchip gasification equilibrium chemistry MATLAB simulation.
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Energetic and Exergetic Analysis of Organic Rankine Cycle Powered by Hot Geothermal Water
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作者 Fathi Latrash Mohammed A. Al-Weshahi +1 位作者 Basim M.A Makhdoum Brian Agnew 《Journal of Energy and Power Engineering》 2014年第7期1217-1231,共15页
The paper presents an investigation of energy and exergy analysis of an existing ORC (organic rankine cycle) unit powered by hot geothermal water. The validated model of this unit was used to examine 25 refrigerants... The paper presents an investigation of energy and exergy analysis of an existing ORC (organic rankine cycle) unit powered by hot geothermal water. The validated model of this unit was used to examine 25 refrigerants belonging to different chemical compositions. The study revealed that R141b and R123 produced the best net power, energy efficiency, and exergy efficiency, whereas R125 was the lowest. Hydrofluorocarbons (except R143a), hydrocarbons, and inorganic reflected attractive energy and exergy efficiencies. All investigated mixtures gained low performance compared with other studied candidates. The R245ca was the best among the hydrofluorocarbons studied refrigerants, and R501 was the best among the mixture refrigerants. Furthermore, within the ORC system, the evaporator was found to have the highest exergy destruction and the refrigerant pump was the lowest. 展开更多
关键词 Organic Rankine cycle EXERGY ENERGY refrigerants.
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Korean Wave: Towards Regional Cultural Diffusion?
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作者 Seiko Yasumoto 《Journal of Literature and Art Studies》 2013年第2期101-112,共12页
The aim of this paper is firstly to determine if the Korean television drama Winter Sonata and its spinoffs are contributing to contemporary cross-cultural diffusion in Japan. Secondly, if cross-cultural diffusion is ... The aim of this paper is firstly to determine if the Korean television drama Winter Sonata and its spinoffs are contributing to contemporary cross-cultural diffusion in Japan. Secondly, if cross-cultural diffusion is occurring, is it contributing to a loss of local identity? Winter Sonata is a small but significant part of the Korean Wave and in the vanguard of Korean television drama content viewed in Japan. There have been macro political changes in East Asia, largely driven by Korea, resulting in an easing of restrictions on cross-border media trade. These in turn have progressively created a new dynamic in content and volume. The methodology used for the study is triangulation including document analysis, audience analysis, and commercial outcomes. The convergent validation derived from the three parameters advances the proposition that Winter Sonata has contributed to cultural diffusion from a Japanese perspective but not to a loss of local identity. Arguably, the process is an enriching one in East Asia reinforced by multi-lateral media trade. 展开更多
关键词 popular culture Korean Wave cross-cultural diffusion cultural hybridity TRIANGULATION
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The study of relationship between textile and garment market,industry cluster and regional economy development
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作者 Ye Hang Qu Hongjian 《International English Education Research》 2015年第3期85-90,共6页
China's textile and garment markets grown up with the development of reform and opening-up, they're well adapted to the national policy and economic environment in each period, and formed a large-scale development, ... China's textile and garment markets grown up with the development of reform and opening-up, they're well adapted to the national policy and economic environment in each period, and formed a large-scale development, played a positive role in promoting China's economy development. This paper has a research on the textile and garment market, industry cluster and regional economy, recognize textile professional market and regional economy as the main research object, industrial cluster as the intermediary variable. Establish textile and garment market, industrial cluster, regional economy as the main trunk of structural equation model and carry on the empirical analysis. From the empirical analysis, this paper find that the coefficient of textile and garment market effecting on industrial cluster is 0.91, and industrial cluster on regional economy is 0.93, that means results verify hypothesis relationships between the three of them Finally, according to each path coefficients, providing relevant suggestions for the Shanghai area development of textile and garment market, related industries cluster and regional economy development. 展开更多
关键词 textile and garment market industry cluster regional economy structural equation model SHANGHAI
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Research on Cultivating Dynamic Comparative Advantag.es of Chinese Industries
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作者 王岳平 《China Economist》 2013年第3期16-25,共10页
This paper theoretically analyzes the lock-in mechanism of labor division for developing countries when they stick to static comparative advantages and the internal mechanism of cultivating dynamic comparative advanta... This paper theoretically analyzes the lock-in mechanism of labor division for developing countries when they stick to static comparative advantages and the internal mechanism of cultivating dynamic comparative advantages. Through empirical analysis, this paper finds that China, while sharing the benefits of globalization, showcases the lock-in effect regarding its status in the international labor division chain. The analysis finds that in its participation in globalization, the net barter terms of trade ~BTT) and factorial terms of trade for China are deteriorating, and the income terms of trade are seriously overvalued, resulting in a series of contradictions, such as scanty returns for enterprises, slow income growth, increasing trade frictions, and intensified environmental and resource pressures. The paper analyzes rapidly changing factors in China's comparative advantages and characteristics of the changes in industries where China possesses comparative advantages. According to changes in different types of industries at different stages, this paper puts forward suggestions on direction and policies for cultivating dynamic comparative advantages. 展开更多
关键词 comparative advantage INDUSTRY terms of trade
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From Sequential to Parallel Growth of Cities: Theory and Evidence from Canada
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作者 SHENG Kerong FAN Jie +1 位作者 SUN Wei MA Hailong 《Chinese Geographical Science》 SCIE CSCD 2016年第3期377-388,共12页
This paper examines city growth patterns and the corresponding city size distribution evolution over long periods of time using a simple New Economic Geography(NEG) model and urban population data from Canada. The mai... This paper examines city growth patterns and the corresponding city size distribution evolution over long periods of time using a simple New Economic Geography(NEG) model and urban population data from Canada. The main findings are twofold. First, there is a transition from sequential to parallel growth of cities over long periods of time: city growth shows a sequential mode in the stage of rapid urbanization, i.e., the cities with the best development conditions will take the lead in growth, after which the cities with higher ranks will become the fastest-growing cities; in the late stage of urbanization, city growth converges according to Gibrat′s law, and exhibits a parallel growth pattern. Second, city size distribution is found to have persistent structural characteristics: the city system is self-organized into multiple discrete size groups; city growth shows club convergence characteristics, and the cities with similar development conditions eventually converge to a similar size. The results will not only enhance our understanding of urbanization process, but will also provide a timely and clear policy reference for promoting the healthy urbanization of developing countries. 展开更多
关键词 sequential city growth Gibrta′s law finite mixture model convergence club Canada
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CO2 Marginal Abatement Cost and Determinants——An Empirical Analysis of Sample Cities in China
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作者 魏楚 《China Economist》 2015年第1期102-127,共26页
This paper investigates the marginal abatement cost (MAC) of CO: emissions across 104 Chinese cities between 2001 and 2008. Based on parametric directional distance function, this paper discovers that the mean marg... This paper investigates the marginal abatement cost (MAC) of CO: emissions across 104 Chinese cities between 2001 and 2008. Based on parametric directional distance function, this paper discovers that the mean marginal abatement cost of CO2 emissions for sample cities was 967 yuan/ton. In terms of region, CO: marginal abatement cost is significantly higher in China's eastern region than in central and western regions; in terms of provincial-level region, it is the highest in Shanghai and the lowest in Shaanxi in terms of city, it is the highest in Shanghai and the lowest in Zhangjiajie with the ratio between their medians being at 48:1; in terms of time, marginal abatement cost has been always on the rise with significant intercity disparities. There is a U-shaped curve relationship between marginal abatement cost of cities and CO2 emissions per unit of GDP, which is negatively correlated with the share of secondary industry and positively correlated with the level of urbanization. 展开更多
关键词 marginal abatement cost CO2 driving force China CITY
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中药品种理论七论
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作者 华兰香 姜胜昌 华国智 《首都医药》 2001年第4期55-55,共1页
中药品种传统经验鉴别辨状论质论   辨证论治是中医理论的精髓,中药品种传统经验鉴别的精髓是辨状论质,主要是根据药材的外观性状(形、色、气、味)所表现出来的特征来判断药材的真伪优劣。例如野生人参比园参质量好,人参皂甙含量... 中药品种传统经验鉴别辨状论质论   辨证论治是中医理论的精髓,中药品种传统经验鉴别的精髓是辨状论质,主要是根据药材的外观性状(形、色、气、味)所表现出来的特征来判断药材的真伪优劣。例如野生人参比园参质量好,人参皂甙含量高,这是人所共知的。经验鉴别形容野生人参“芦长、碗密、枣核丁、紧皮细纹、珍珠须”,仅仅用了14个汉字,就道出了它与栽培的园参的重要区别点;黄柏以色黄者为佳,颜色的深浅与小檗碱的含量多少密切相关等。因此传统经验鉴别具有简便、快速、节省费用和基本准确的优点,当然还要配合其它鉴定方法,可收相辅相成之效。   中药材地区习惯用药渐趋分化论   中药材的地区习惯用药非常不规范,同名异物和同物异名现象,使中药品种十分混乱。如五加皮在2000年版《中国药典》记载,五加科植物细柱五加的根皮为正品,而在北方大部分地区则以香加皮作五加皮药用,其科属、有效成分、药理、功效、作用均与正品五加皮不同。因此看待地区习惯用药要持正确态度,应该是积极研究,促其分化,按其本质分类处理。经过研究,凡够条件的向收入地方标准方向分化,不符合条件的列入混乱品种并淘汰。   中药混乱品种与伪品隐现有时论   中药混乱品种与伪品的隐现规律,分滋生、扩展、隐蔽和复现四段历程。滋生必有其适宜的土壤和气候等条件,如当正品道地药材缺货、供求发生矛盾时,则混乱品种与伪品即乘虚而入,混进市场,以假乱真,尤以珍贵药材为最。混乱品种与伪品一旦滋生出现以后,如不立即纠正、清除,就很容易扩展蔓延,导致恶性流行。其扩展面积和影响的大小,通常随品种而异,或四处扩展,或就近扩散。其制伪手段,表现形式等也常常花样翻新,尤其是在不断遭到有关部门的处理后,其隐蔽的程度也越深。但这种隐蔽是暂时性的、阶段性的,而绝非是长远性的,尔后若逢适当时机,还会卷土重来。总结其特性亦有四点,即必然性、危害性,阶段性和顽固性。针对其特性和隐现规律,即可制订出有效的综合治理措施。 展开更多
关键词 中药品种 辨状论质论 地区 分化证 隐现有时论 开发护育并举论 代用品认识论
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Empirical analysis of network measures for predicting high severity software faults 被引量:4
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作者 Lin CHEN Wanwangying MA +4 位作者 Yuming ZHOU Lei XU Ziyuan WANG Zhifei CHEN Baowen XU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第12期198-215,共18页
Network measures are useful for predicting fault-prone modules. However, existing work has not distinguished faults according to their severity. In practice, high severity faults cause serious problems and require fur... Network measures are useful for predicting fault-prone modules. However, existing work has not distinguished faults according to their severity. In practice, high severity faults cause serious problems and require further attention. In this study, we explored the utility of network measures in high severity faultproneness prediction. We constructed software source code networks for four open-source projects by extracting the dependencies between modules. We then used univariate logistic regression to investigate the associations between each network measure and fault-proneness at a high severity level. We built multivariate prediction models to examine their explanatory ability for fault-proneness, as well as evaluated their predictive effectiveness compared to code metrics under forward-release and cross-project predictions. The results revealed the following:(1) most network measures are significantly related to high severity fault-proneness;(2) network measures generally have comparable explanatory abilities and predictive powers to those of code metrics; and(3) network measures are very unstable for cross-project predictions. These results indicate that network measures are of practical value in high severity fault-proneness prediction. 展开更多
关键词 network measures high severity fault-proneness fault prediction software metrics
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Semi-synthesis of disulfide-linked branched tri-ubiquitin mimics 被引量:2
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作者 Yanyan Si Lujun Liang +3 位作者 Shan Tang Yunkun Qi Yong Huang Lei Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第4期412-417,共6页
Ubiquitin(Ub) chain isopeptide bond mimics are useful molecules for biochemical and biophysical studies. Herein, we report the semi-synthesis of the disulfide-linked K11/K48-branched tri-Ub(Ub_3^(11/48)(S-S)), the fir... Ubiquitin(Ub) chain isopeptide bond mimics are useful molecules for biochemical and biophysical studies. Herein, we report the semi-synthesis of the disulfide-linked K11/K48-branched tri-Ub(Ub_3^(11/48)(S-S)), the first example of an isopeptide mimic for the branched Ub chains,which have recently emerged as an interesting category of Ub modifications. Our strategy comprised the El-dependent synthesis of the Ub conjugate of aminoethanethiol, followed by disulfide formation with Ub(K11 C, K48 C). The structure of the synthetic isopeptide bond mimics was verified by the crystal structure of Ub_3^(11/48)(S-S). Deubiquitination and pulldown assays indicated that the synthetic Ub_3^(11/48)(S-S) could be hydrolyzed by linkage-specific deubiquitinases(K11-specific Cezanne and K48-specific OTUB1), and recognized by proteasomal ubiquitin receptor S5 a. 展开更多
关键词 ubiquitin chain isopeptide bond mimics disulfide-directed strategy branched Ub chains crystal structure
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Formal Analysis of Authentication in 802.11i
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作者 董玲 陈克非 来学嘉 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第1期122-128,共7页
Authentication is the basis of the security of IEEE 802.11i standard. The authentication process in 802.11i involves two important protocols: a 4-way handshake and a group key handshake. A formal analysis of authenti... Authentication is the basis of the security of IEEE 802.11i standard. The authentication process in 802.11i involves two important protocols: a 4-way handshake and a group key handshake. A formal analysis of authentication in 802.11i is given via a belief multisets formalism. The analysis shows that the 4-way handshake and the group key handshake may provide satisfactory mutual authentication, key management, and issue of a new group temporal key from an access point to a user device, under the guarantee of mutual possession of a confidential palrwise master key. The analysis also shows that there exists a denial of service attack in the 4-way handshake and some seeming redundancies are useful in the protocol implementation. 展开更多
关键词 IEEE 802.11i AUTHENTICATION protocol analysis
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A quantification model of Traditional Chinese Medicine syndromes in children with idiopathic precocious puberty and early puberty 被引量:9
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作者 Yanyan Lin Yuanyuan Xue +6 位作者 Jian Yu Yonghong Wang Wen Sun Yanyan Sun Yumin Shi Yiqun Zhang Hong Hu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第5期630-636,共7页
OBJECTIVE:To establish a quantification model of Traditional Chinese Medicine(TCM)syndromes by sampling patients undergoing idiopathic precocious puberty(IPP)and early puberty.METHODS:A questionnaire for classifying a... OBJECTIVE:To establish a quantification model of Traditional Chinese Medicine(TCM)syndromes by sampling patients undergoing idiopathic precocious puberty(IPP)and early puberty.METHODS:A questionnaire for classifying and quantifying TCM syndromes was designed and administered.All the results were analyzed;the relationship between 3 types of syndrome and 47symptoms were summated.Meanwhile,the frequency distribution of each symptom or sign was aggregated.Fuzzy mathematics was used to develop a quantification model ofTCM syndromes.RESULTS:We found that precocious puberty had 3types of syndrome,including hyperactivity of fire due to Yin deficiency(Syndrome I),depressed liver Qi transforming into fire(Syndrome II),and end retention of damp heat(Syndrome III).In the IPP group,Syndrome I was the most common principal syndrome(100%).Forty-six patients(43.81%)werediagnosed with Syndrome I accompanied by Syndrome II and 11(10.48%)were diagnosed with Syndrome I accompanied by Syndrome III.In the early puberty group,Syndrome I was also the main syndrome(98.39%).The degrees of most symptoms were mild to moderate.Reddened tongue was the most common tongue manifestation(62.86%prevalence)in the IPP group.The most common pulse manifestations were slippery pulse,thread pulse,and taut pulse.The Asymptotic Normalization Coefficient(ANC)method was used to quantify the TCM syndromes in 167 cases.Diagnostic accuracy rate reached 91%,comparable to expert diagnosis.CONCLUSION:We find that there are 3 types of syndrome in the IPP group and in the early puberty group.Syndrome I(hyperactivity of fire due to Yin deficiency)is the main syndrome in the two groups.ANC may be an appropriate for quantification model ofTCM syndromes. 展开更多
关键词 Puberty precocious Medicine Chinese traditional Symptom complex Fuzzy mathematics Cluster analysis Asymptotic normalization coefficient
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GRACE terrestrial water storage data assimilation based on the ensemble four-dimensional variational method PODEn4DVar:Method and validation 被引量:3
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作者 SUN Qin XIE ZhengHui TIAN XiangJun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第3期371-384,共14页
Seasonal and interannual changes in the Earth's gravity field are mainly due to mass exchange among the atmosphere,ocean,and continental water sources.The terrestrial water storage changes,detected as gravity chan... Seasonal and interannual changes in the Earth's gravity field are mainly due to mass exchange among the atmosphere,ocean,and continental water sources.The terrestrial water storage changes,detected as gravity changes by the Gravity Recovery and Climate Experiment(GRACE) satellites,are mainly caused by precipitation,evapotranspiration,river transportation and downward infiltration processes.In this study,a land data assimilation system LDAS-G was developed to assimilate the GRACE terrestrial water storage(TWS) data into the Community Land Model(CLM3.5) using the POD-based ensemble four-dimensional variational assimilation method PODEn4 DVar,disaggregating the GRACE large-scale terrestrial water storage changes vertically and in time,and placing constraints on the simulation of vertical hydrological variables to improve land surface hydrological simulations.The ideal experiments conducted at a single point and assimilation experiments carried out over China by the LDAS-G data assimilation system showed that the system developed in this study improved the simulation of land surface hydrological variables,indicating the potential of GRACE data assimilation in large-scale land surface hydrological research and applications. 展开更多
关键词 data assimilation land surface model terrestrial water storage ensemble four-dimensional variational data assimilation method
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