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1.
软件工程方法述评   总被引:1,自引:0,他引:1  
对一些流行的软件工程方法,包括结构化方法、形式化方法、面向对象方法、基于构件的方法、基于Agent的方法、基于净室技术的方法、基于敏捷技术的方法等进行了述评,并对软件工程方法的发展趋势进行了初步探讨.  相似文献   

2.
体育学习方法指导是提高体育学习能力的一种教学方法。突破心理障碍,从学习心理考虑体育学习方法指导的特点,及时进行体育学习方法指导是体育学习方法指导的心理条件。体育学习方法指导与非智力因素培养相结合,身体练习方法指导与心理练习方法指导相结合,体育学习方法指导与教学方法改革要同步是体育学习方法指导的心理学原则。开设体育学习方法指导讲座,渗入体育学习方法指导,迁移性体育学习方法的指导,学生团体学习指导,指导学生对自我动作的反馈是体育学习方法指导的方法。  相似文献   

3.
在认知诊断评估中,构建正确测验Q矩阵十分关键,但比较困难.该文将确定性输入噪音与门模型下3种在线标定方法(极大似然估计方法,边际极大似然估计方法和交差方法)用于测验Q矩阵修正,并与δ方法,γ方法和最小残差平方和方法进行比较.采用模拟研究验证和比较各方法的表现,研究结果显示:边际极大似然估计方法表现良好,交差方法次之; 项目所考查的属性数目是影响δ方法和γ方法的表现.  相似文献   

4.
马志凌  郑学仁 《科学技术与工程》2007,7(8):1695-17001706
测量正在工作的半导体器件温度有很多种方法。这些方法大概可以分为三类:电学方法、光学方法和物理接触方法。介绍了各种方法的物理基础,并且对每种方法的优势、劣势以及空间解析度及需要特别注意的问题等进行了讨论。  相似文献   

5.
许多高职院校都在寻找激励教师的有效方法,实际上激励方法是有层次的,对不同的激励对象实施不同的方法会起到更好的效果。三个层次的激励方法,即基本激励方法、特殊激励方法和无形激励方法可针对不同的激励对象实施。  相似文献   

6.
SEREX方法在肿瘤相关抗原筛选中的应用   总被引:1,自引:0,他引:1  
SEREX方法是筛选肿瘤抗原分子的一种方便且高效的方法。本文解释了SEREX的原理及方法,介绍了利用该方法所鉴定出来的肿瘤相关抗原,讨论了该方法的优缺点,阐述了改进的方法,最后对该方法的应用进行了展望。  相似文献   

7.
对AHM模型2种基于IRT的判别方法——方法 A和方法 B进行改良,得到方法 C和方法 D.通过蒙特卡洛模拟试验考察A、B、C、D等4种方法的诊断性能.结果表明:蒙特卡洛模拟试验的结果与理论研究结果相符,方法 C优于方法 A,方法 D优于方法 B,且从总体上看新方法的评价指标比对应原方法的评价指标有较大幅度的提高.  相似文献   

8.
利用精确解方法、升降算符方法、平移算符方法和微扰近似方法推导出了一维电谐振子的定态能量和波函数,结果表明升降算符方法和平移算符方法较精确解方法推导过程更加简洁,微扰近似方法得到的结果与三种方法得到的结果是一致的。  相似文献   

9.
为了探讨确定子空间识别(DSI)方法与确定-随机子空间识别(CDSI)方法在实际应用中的性能,开展了DSI方法与CDSI方法的对比研究。首先,对DSI方法与CDSI方法的算法原理进行介绍,对比了过程噪声和测试噪声在2种方法中不同的考虑方式,分析了CDSI方法在算法层面的优势。以大比尺斜拉桥模型振动台试验为依托,获取模型桥在4种不同强度等级的集集(Chichi)地震动激励下的加速度响应,为考察DSI方法与CDSI方法的算法性能提供数据支撑。然后,分别使用DSI方法与CDSI方法对模型桥的模态参数进行识别,使用稳定图对模态参数识别结果进行展示,并统计了图中稳定点个数,对比2种方法模态参数识别结果的稳定性。最后,对DSI方法与CDSI方法的振型识别结果进行展示,并统计2种方法的振型模态置信准则值(MAC),对比了2种方法振型识别结果的差异。结果表明:DSI方法与CDSI方法识别得到的频率与阻尼比基本一致,但CDSI方法识别结果的稳定性略优;DSI方法比CDSI方法识别得到的振型幅值略大,经量纲一化处理后,2种方法识别的振型形状基本一致,但随着模态阶次的增高和激励强度的增强,两者振型的差异逐渐增大;CDSI方法考虑了数据中的过程噪声和测试噪声,其模态参数识别结果的稳定性略优于DSI方法,但同时其也降低了CDSI方法的计算效率,CDSI方法的优势并不是压倒性的。  相似文献   

10.
后方法时代宣布"方法"已死,那么"方法"真的死了吗?如果"方法"已死,现在的外语教学舞台上又是谁在表演?在对方法时代的众方法和后方法进行分析研究后指出后方法是方法的继承与发展,并从宏观的角度阐释了方法的选择、使用和整合。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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