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1.
介词主要表达事物间的关系,它反映在句子结构上就是一种句式。nit。句式的基本形式可概括为:“TR+V+into+LM”或“V+TR+ into+LM”。表示TR由于力的作用从外部移动到LM的内部。本文从认知角度主要研究介词nito句式的引申机制。  相似文献   

2.
Many studies investigating cue competition have focused on the blocking effect. We investigated the blocking effect with pigeons using a landmark-based spatial search task in both a touchscreen preparation (Exp. 1a) and an automated remote environmental navigation apparatus (Exp. 1b). In Phase 1, two landmarks (LMs: A and Z) appeared on separate trials as colored circles among a row of eight (touchscreen) or six (ARENA) identical response units. Subjects were rewarded for pecking at a target response unit to the right of LM A and to the left of an extraneous LM, Z. During the blocking trials in Phase 2, LM X was presented in compound with a second LM (A) that had been previously trained. On control trials, LM Y was presented in compound with LM B and a target in the same manner as in the trials of AX, except that neither landmark had previously been trained with the target. All subjects were then tested with separate trials of A, X, B, and Y. Testing revealed poor spatial control by X relative to A and Y. We report the first evidence for a spatial-blocking effect in pigeons and additional support for associative effects (e.g., blocking) occurring under similar conditions (e.g., training sessions, spatial relationships, etc.) in 3-D and 2-D search tasks.  相似文献   

3.
"光控定时装置"由光敏电阻、晶体三极管、晶体二极管、与非门集成电路CD4011、555定时器、集成运算放大器LM324、继电器、定时琴键选择开关及工作指示发光二极管等元件组成.集成电路CD4011的四个门均接成"与"输入,以检测环境输入端的亮、暗状态.555定时器接成单稳态触发电路形式,运放集成块LM324接成电压跟随器与电压比较器的电路形式.  相似文献   

4.
We evaluate the performance of the most common estimators of latent Markov (LM) models with covariates in the presence of direct effects of the covariates on the indicators of the LM model. In LM modeling it is common practice not to model such direct effects, ignoring the consequences that might have on the overall model fit and the parameters of interest. However, in the general literature about latent variable modeling it is well known that unmodeled direct effects can severely bias the parameter estimates of the model at hand. We evaluate how the presence of direct effects in?uences the bias and efficiency of the 3 most common estimators of LM models, the 1-step, 2-step, and 3-step approaches. Furthermore, we propose amendments (that were thus far not used in the context of LM modeling) to the 2- and 3-step approaches that make it possible to account for direct effects and eliminate bias as a consequence. This is done by modeling the (possible) direct effects in the first step of the stepwise estimation procedures. We evaluate the proposed estimators through an extensive simulation study, and illustrate them via a real data application. Our results show, first, that the augmented 2-step and 3-step approaches are unbiased and efficient estimators of LM models with direct effects. Second, ignoring the direct effects leads to biased estimates with all existing estimators, the 1-step approach being the most sensitive.  相似文献   

5.
为了获得光束质量较好、光斑尺寸较小、功率密度较高的、适合激光加工的激光束,对激光加工中的高斯光束进行传输与变换.先对高斯光束的特性及其传输变换进行了理论分析,而后在实际中加以验证.结果表明,经过这种传输变换后可获得光斑直径较小的、功率密度较高的、可用于激光加工的激光束.说明这种传输变换是可行有效的.  相似文献   

6.
7.
Two Lagrange multiplier (LM) methods may be used in specification searches for adding parameters to models: one based on univariate LM tests and respecification of the model (LM‐respecified method) and the other based on a partitioning of multivariate LM tests (LM‐incremental method). These methods may result in extraneous parameters being included in models due to either sampling error or the model being misspecified. A 2‐stage specification search may be used to reduce errors due to misspecification. In the 1st stage, parameters are added to models based on LM tests to maximize fit. Second, parameters added in the 1st stage are deleted if they are no longer necessary to maintain model fit. Illustrations are presented to demonstrate that errors due to misspecification occur with the LM‐respecified method and are even more likely with the LM‐incremental approach. These illustrations also show how the deletion stage can help eliminate some of these errors.  相似文献   

8.
This longitudinal study investigated growth in reading-related skills between Grade 1 and 4 for language minority (LM) learners and their native English-speaking classmates from similarly low socioeconomic backgrounds (N = 166). Growth trajectories were compared by language background and by Grade 4 reading difficulties, with the goal of informing decisions about how early LM learners can undergo screening for risk of reading difficulties. As a group, LM learners demonstrated weaknesses in vocabulary and oral comprehension and strengths in phonological awareness that were apparent in Grade 1 and consistent through Grade 4. LM learners also demonstrated early strengths in letter-word identification but fell far below national norms by Grade 4. The subset of LM learners with word reading difficulties demonstrated major weaknesses in vocabulary, oral comprehension, phonological awareness, and working memory, whereas LM learners with specific reading comprehension difficulties demonstrated major weaknesses in vocabulary and oral comprehension; these weaknesses were apparent in Grade 1 and consistent through Grade 4, suggesting the importance of early assessment and intervention.  相似文献   

9.
三端可调型正电压输出稳压电路LM317在LED显示电路中可以替代LED显示器的限流电阻.这种接法在驱动合适数目的LED时.具有独特的优点.  相似文献   

10.
We examined the efficacy of 20 weeks of individual supplemental phonics-based instruction for language minority (LM) and non-LM first graders. Students were designated LM if the primary home language was not English (otherwise non-LM). Those performing in the bottom half of their classroom LM/non-LM group in letter knowledge and phonological awareness were randomly assigned to treatment and control conditions. Treatment included alphabetics, decoding, and oral reading practice. Results showed that treatment students (n?=?93) outperformed controls (n?=?94) on 5 of the 6 posttests; however, LM students exhibited lower treatment response on passage reading fluency. Pretest word reading did not moderate treatment response, and LM students with greater baseline vocabulary showed greater treatment response on posttest word reading and spelling.  相似文献   

11.
LM87具有对板级系统的温度、电压、风扇转速的监控能力。本文介绍12C总线的特点,以及用AT89C51的I/O口模拟12C总线实现对LM87的控制的方法。  相似文献   

12.
介词是表达事物间的关系 ,反映在句子结构上就是一种句式。on句式的基本形式可概括为 :TR +on +LM ,表示某一物体处在另一物体之上 ,并有接触关系。本文从认知角度来研究介词on句式的引申机制  相似文献   

13.
针对LM算法及模拟退火算法各自存在的不足,提出一种交替使用二者的混合优化算法(SALM算法).该算法先通过模拟退火算法粗调得到一组全局最优近似解,再以该近似解为初值,交替使用模拟退火算法和LM算法,直至发现满意的最优解.实验结果表明,新算法不但具有模拟退火算法的全局收敛特性而且保留了LM算法的局部收敛速度,克服了单纯模拟退火算法所产生的随机性和概率性问题,也弱化LM算法对初始条件的依赖程度,保证了求解的速度和精度。  相似文献   

14.
介词表达事物间的关系,它反映在句子结构上就是一种句式。at句式的基本形式可概括为:TR at LM,表示某一物体处在另一物体的某一点。本从认知角度主要研究介词at句式的引申机制。  相似文献   

15.
本文报道了安徽省皇甫山黄精属 (PolugonatuMill)五种植物在LM下表皮气孔的五项指标 :气孔类型、气孔分布特征及气孔指数等。旨在为进一步探讨百合科植物属种间关系提供资料  相似文献   

16.
目的:通过比较国标法、real—timePcR法和LAMP方法,得到适合基层实验室快速检测单核细胞增生李斯特菌的方法。方法:分别用国标法、real-timePcR法和环介导的等温扩增(100p—mediated isothermal amplification,LAMP)法检测李斯特菌,并进行方法比较。结果:三种方法对单增李斯特菌的检测结果一致.国标法整个检测过程需5~7d;real—timePCR法实验条件要求高,成本高,检测需1.5~2.5d;LAMP法实验条件低,成本低,检测时限与real—timePCR相同。结论:LAMP~检测单增李斯特菌灵敏度高、特异性强、快速高效和低成本,适合基层实验室应急检测和现场监测使用。  相似文献   

17.
刘子华预言的木王星应该是2002年发现的行星2002LM60(Quaoar).根据最新的观测结果,有学者定量论证了太阳系的八大行星模式:它是对称的四个类地行星和小行星带;四个类木行星和柯伊伯带(包括冥王星).  相似文献   

18.
LM567及其在测距中的应用   总被引:1,自引:0,他引:1  
介绍了LM567的组成及应用电路,重点介绍了将其用于超声波检测时对输入信号的要求及外围元件的要求。给出了以LM567作为检测元件的超声波测距电路及测量程序流程图。实验表明使用LM567作为超声检测集成电路具有较高的性能价格比。  相似文献   

19.
LM331及其应用   总被引:6,自引:0,他引:6  
简要介绍了LM331及其V/F(F/V)基本转换电路的连接方法;并通过检测与转换中的三种应用实例来分析与说明LM331的应用价值。  相似文献   

20.
神经网络作为人工智能的一个分支,已在众多领域得到成功运用,把它用在教学领域还是一个新的尝试.结合多元智能理论,以学生的多元智能光谱为处理对象,建立了一个BP神经网络,利用LM算法和MATLAB语言,通过网络训练,得到了一种学生素质的处理方法.  相似文献   

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