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复数射线时间叙事与小说叙事立体空间的建构 被引量:2
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作者 刘宏志 《河南师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2019年第5期136-144,共9页
外部环境的变化,以及人们对世界认知的变化,使小说传统的线性叙事面临着危机这种叙事显得把世界简单化了。但是另一方面,小说叙事的特质又是线性的。近年来在长篇小说叙事中,一种新的,我称之为复数射线时间叙事模式兴起,这种叙事模式中... 外部环境的变化,以及人们对世界认知的变化,使小说传统的线性叙事面临着危机这种叙事显得把世界简单化了。但是另一方面,小说叙事的特质又是线性的。近年来在长篇小说叙事中,一种新的,我称之为复数射线时间叙事模式兴起,这种叙事模式中,在一条主叙事轴上会存在多个分叉叙事,从而对主叙事轴进行了有效的丰富。通过这种复数射线时间叙事模式,小说有效建构起一个立体叙事空间,从而呈现了更为复杂的现实。 展开更多
关键词 线性叙事 复数射线时间叙事 立体空间建构
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量子力学中电子隧穿势垒的时间 被引量:5
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作者 顾本源 《北京石油化工学院学报》 2002年第4期64-68,共5页
简要地介绍各种形式的粒子隧穿势垒时间的定义,并且评论了它们的适用范围。同时介绍有关电子隧穿势垒时间方面的实验测量和结果。
关键词 势垒隧穿 居留时间 反射时间 相位时间τo 拉莫尔进动时间 B^..uttiker-Landauer时间 复数时间
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The Calculation of Parameters for DNA Kinetic Structure Based on Monte-Carlo Multiple Integrals 被引量:1
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作者 崔向军 蔡禄 《Agricultural Science & Technology》 CAS 2010年第5期5-6,16,共3页
Based on protein-DNA complex crystal structural data in up-to-date Nucleic Acid Database,the related parameters of DNA Kinetic Structure were investigated by Monte-Carlo Multiple Integrals on the base of modified DNA ... Based on protein-DNA complex crystal structural data in up-to-date Nucleic Acid Database,the related parameters of DNA Kinetic Structure were investigated by Monte-Carlo Multiple Integrals on the base of modified DNA structure statistical mechanical model,and time complexity and precision were analyzed on the calculated results. 展开更多
关键词 Monte-Carlo method Multiple integrals DNA Time complexity Precision
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Minimally Invasive Perventricular Device Closure of Ventricular Septal Defect: a Comparative Study in 80 Patients 被引量:7
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作者 Xin-chao Yang De-bin Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2014年第2期98-102,共5页
Objective To evaluate the efficacy of minimally invasive perventricular device closure of ventricular septal defect(VSD). Methods Between September 2011 and February 2013, we collected 40 patients who underwent perven... Objective To evaluate the efficacy of minimally invasive perventricular device closure of ventricular septal defect(VSD). Methods Between September 2011 and February 2013, we collected 40 patients who underwent perventricular closure via a small lower sternal incision(minimally invasive group), aged 15.5±3.5 years(12 months to 32 years) with a body weight of 24.2±7.5 kg(10.8-58.0 kg). The mean size of VSD was 5.6±0.5 mm(2-14 mm). Another 40 patients were included as the surgical group, receiving the conventional surgical repair of VSD. The device of the minimally invasive group was released under the guidance of transesophageal echocardiography. Success rate, cardiac indicators, and clinical outcomes of the 2 groups were compared. Results The patients in the surgical group and those in the minimally invasive group showed similar results in success rate(both 97.5%). The procedure time, intensive care unit stay, hospital stay, and postoperative recovery time in the minimally invasive group were significantly shorter than those in the surgical group(58±21 minutes versus 145±26 minutes, 2±1 days versus 8±3 days, 5±1 days versus 16±6 days, 3±1 days versus 90±20 days, all P<0.05). The minimally invasive group had a higher incidence of conduction anomalies(17.5% versus 2.5%, P<0.05). In the follow-up period of 3-12 months, there was no new residual shunt, noticeable aortic regurgitation, significant arrhythmias, or device failure except for new complications in the surgical group. Conclusions The success rate of minimally invasive perventricular device closure of VSD under transesophageal echocardiography guidance is similar to that of conventional surgical repair, but the short-term outcomes of the minimally invasive approach is much better. Long-term follow-up is necessary to confirm the effectiveness of this technique. 展开更多
关键词 transesophageal echocardiography minimally invasive ventricular septal defect
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Effects of Low-Intensity Ultrasound on Cell Proliferation and Reproductivity
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作者 杨春梅 蒋学慧 +1 位作者 杜康 蔡启亮 《Transactions of Tianjin University》 EI CAS 2016年第2期125-131,共7页
Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parameter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, lowinten... Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parameter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, lowintensity ultrasound stimulation on the proliferation and reproductivity of Hep G2 and 3T3 cells in vitro was examined with a 1.06 MHz-generator by changing the parameters(including intensity, pulse repetition frequency and duty cycle)in a wide range. Cell viability and reproductivity at different time after sonication were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and colony formation assay to indicate timerelated proliferation. The results illustrate that ultrasound irradiation at 0.4—0.8 W/cm^2 and high pulse repetition frequency(100 Hz)can facilitate cell proliferation, while above 0.8 W/cm^2 would resist it. The extent of resistance closely correlated with duty cycle and pulse repetition frequency. Resistance effect at low pulse repetition frequency(1 Hz)is greater than that at high pulse repetition frequency(100 Hz)and not time-related. The influence of high pulse repetition frequency is time-accumulated, indicating cellular process involved. These findings would provide valuable guidelines for the application of low-intensity ultrasound in stem cell transformation and tissue engineering. 展开更多
关键词 low-intensity ultrasound cell viability cell morphology cell proliferation cell reproductivity
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Sorting Data Elements by SOCD Using Centralized Diamond Architecture
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作者 Masumeh Damrudi Kamal Jadidy Aval 《Computer Technology and Application》 2011年第5期374-377,共4页
Several parallel sorting techniques on different architectures have been studied for many years. Due to the need for faster systems in today's world, parallelism can be used to accelerate applications. Nowadays, para... Several parallel sorting techniques on different architectures have been studied for many years. Due to the need for faster systems in today's world, parallelism can be used to accelerate applications. Nowadays, parallel operations are used to solve computer problems such as sort and search, which result in a reasonable speed. Sorting is one of the most important operations in computing world. The authors always try to find the best in different areas which the premier is speedup. In this paper, the authors issued a sort with O(logn) time complexity on PRAM EREW (Parallel Random Access Machine Exclusive Read Exclusive Write). The algorithm is designed in a manner that keeps the tradeoff between the number of processor elements in the architecture and execution time. The simulation of the algorithm proves the theoretical analysis of the algorithm. The results of this research can be utilized in developing faster embedded systems. Sorting on Centralized Diamond (SOCD) algorithm is issued on the novel Centralized Diamond architecture which takes the advantages of Single Instruction Multiple Data (SIMD) architecture. This architecture and the sort on it are intuitive and optimal. 展开更多
关键词 Parallel sorting diamond architecture single instruction multiple data (SIMD) parallel random access machine exclusive read exclusive write (PRAM EREW) sorting on centralized diamond (SOCD).
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Reliability and maintainability analysis of electrical system of drum shearers 被引量:3
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作者 SEYED Hadi Hoseinie MOHAMMAD Ataei +1 位作者 REZA Khalokakaie UDAY Kumar 《Journal of Coal Science & Engineering(China)》 2011年第2期192-197,共6页
The reliability and maintainability of electrical system of drum shearer at Parvade. 1 Coal Mine in central Iran was analyzed. The maintenance and failure data were collected during 19 months of shearer operation. Acc... The reliability and maintainability of electrical system of drum shearer at Parvade. 1 Coal Mine in central Iran was analyzed. The maintenance and failure data were collected during 19 months of shearer operation. According to trend and serial correlation tests, the data were independent and identically distributed (iid) and therefore the statistical techniques were used for modeling. The data analysis show that the time between failures (TBF) and time to repair (TTR) data obey the lognormal and Weibull 3 parameters distribution respectively. Reliability-based preventive maintenance time intervals for electrical system of the drum shearer were calculated with regard to reliability plot. The reliability-based maintenance intervals for 90%, 80%, 70% and 50% reliability level are respectively 9.91, 17.96, 27.56 and 56.1 h. Also the calculations show that time to repair (TTR) of this system varies in range 0.17-4 h with 1.002 h as mean time to repair (MTTR). There is a 80% chance that the electrical system of shearer of Parvade. 1 mine repair will be accomplished within 1.45 h. 展开更多
关键词 drum shearer electrical system reliabilitv maintenance
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Graphical-based data placement algorithm for cloud workflow
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作者 张鹏 Wang Guiling +1 位作者 Han Yanbo Wang Jing 《High Technology Letters》 EI CAS 2014年第2期179-186,共8页
When workflow task needs several datasets from different locations m cloud, data transfer becomes a challenge. To avoid the unnecessary data transfer, a graphical-based data placement algo- rithm for cloud workflow is... When workflow task needs several datasets from different locations m cloud, data transfer becomes a challenge. To avoid the unnecessary data transfer, a graphical-based data placement algo- rithm for cloud workflow is proposed. The algorithm uses affinity graph to group datasets while keeping a polynomial time complexity. By integrating the algorithm, the workflow engine can intelligently select locations in which the data will reside to avoid the unnecessary data transfer during the initial stage and runtime stage. Simulations show that the proposed algorithm can effectively reduce data transfer during the workflow' s execution. 展开更多
关键词 data placement affinity graph cloud computing WORKFLOW data transfer
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Effect of Ultraviolet Aging on Asphalt Rheological Properties
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作者 Wang Jiani Xue Zhongjun +1 位作者 Tan Yiqiu Zhang Lei 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第4期26-32,共7页
This paper simulated the ultraviolet aging process of asphalt and used dynamic mechanic analysis (DMA) method to evaluate the effect of ultraviolet aging on the asphalt theological properties. After having experienc... This paper simulated the ultraviolet aging process of asphalt and used dynamic mechanic analysis (DMA) method to evaluate the effect of ultraviolet aging on the asphalt theological properties. After having experienced ultravio- let aging, the low temperature performance of asphalt binder decreased significantly, with its complex modulus increased and phase angle decreased along with changing rheological properties as compared to the performance of original asphalt binder. The ultraviolet aging process would make asphalt binder more sensitive to brittle and fatigue failure. On the basis of the time-temperature superposition principle (TTSP), the viscoelastic transition frequency (coT) is proposed to evaluate the effect of ultraviolet aging. It is found that with the increase in ultraviolet aging time, the cox moves to the lower frequency range gradually. Since the viscoelastic transition frequency is sensitive to the effect of aging, it can be used as an indicator of ultraviolet aging. 展开更多
关键词 ASPHALT ultraviolet aging rheological properties viscoelastic transition frequency
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船载GNSS-R有效波高测量的初步研究 被引量:5
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作者 李颖 朱雪瑗 +1 位作者 崔璨 杨勇虎 《海洋环境科学》 CAS CSCD 北大核心 2016年第2期180-183,共4页
本文阐述了基于干涉复数场(ICF)相关时间方法的GNSS-R测量有效波高的技术原理,利用大连海事大学教学实习船育鲲轮平台和Oceanpal接收机,进行了国内首次船载GNSS-R有效波高测量实验。通过与船上安装的WAVEX雷达波浪仪数据进行对比,二者... 本文阐述了基于干涉复数场(ICF)相关时间方法的GNSS-R测量有效波高的技术原理,利用大连海事大学教学实习船育鲲轮平台和Oceanpal接收机,进行了国内首次船载GNSS-R有效波高测量实验。通过与船上安装的WAVEX雷达波浪仪数据进行对比,二者之间的一致性验证了船载观测平台的可行性,为深入广泛开展GNSS-R海洋动力环境监测提供了依据。 展开更多
关键词 GNSS-R 有效波高 干涉复数场相关时间方法 船载测量平台
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TWO EFFECTIVE STABILITY CRITERIA FOR LINEAR TIME-DELAY SYSTEMS WITH COMPLEX COEFFICIENTS 被引量:2
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作者 Junyu LI Li ZHANG Zaihua WANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2011年第5期835-849,共15页
This paper presents a method for directly analyzing the stability of complex-DDEs on the basis of stability switches. Two novel criteria are developed for the stability of a class of complex- DDEs. These results not o... This paper presents a method for directly analyzing the stability of complex-DDEs on the basis of stability switches. Two novel criteria are developed for the stability of a class of complex- DDEs. These results not only generalize some known results in literature but also greatly reduce the complexity of analysis and computation. To validate the effectiveness of the proposed criteria, the stabilization problem of the extended time delay auto-synchronization (ETDAS) control and n time delay auto-synchronization (NTDAS) control are then further investigated, respectively. The numerical simulations are consistent with the above theoretical analysis. 展开更多
关键词 Complex coefficient delay feedback control stability switch time-delay.
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