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111.
西方发达国家的就业促进经验及其对中国的启示   总被引:1,自引:0,他引:1  
近年来 ,随着中国改革开放的深入开展 ,城镇失业率迅速上升。西方发达国家在就业领域 ,都曾经历了失业率上升的发展阶段。为降低失业率 ,各国采取了不尽相同但却切实有效的就业促进措施 ,积累了丰富的就业促进经验。中国也可以借鉴这些就业促进经验 ,以期逐步降低失业率  相似文献   
112.
本文分析了中国近 5年来外贸出口增长速度及外贸出口效益的变化趋势 ,并用“增长型衰退”对其加以表述 ;一个国家的外贸出口难于做到线型增长 ,但中国的外贸出口增长速度下滑 ,却跟外贸出口的外延增长方式以及出口商品结构变化缓慢有关。通过创新以提升出口商品结构 ,是我国外贸出口走可持续发展的必由之路  相似文献   
113.
In this paper we investigate the asymptotic critical value behaviour of certain multiple decision procedures as e.g. simultaneous confidence intervals and simultaneous as well as stepwise multiple test procedures. Supposing that n hypotheses or parameters of interest are under consideration we investigate the critical value behaviour when n increases. More specifically, we answer e.g. the question by which amount the lengths of confidence intervals increase when an additional parameter is added to the statistical analysis. Furthermore, critical values of different multiple decision procedures as for instance step-down and step-up procedures will be compared. Some general theoretic results are derived and applied for various distributions.  相似文献   
114.
For given real functionsg andh, first we give necessary and sufficient conditions such that there exists a random variableX satisfying thatE(g(X)|X≥y)=h(y)r x (y),∀y ∈ C x , whereC x andT X are the support and the failure rate function ofX, respectively. These extend the results of Ruiz and Navarro (1994) and Ghitany et al. (1995). Next we investigate necessary and sufficient conditions such thath(y)=E(g(X)|X≥y), for a given functionh. Support for this research was provided in part by the National Science Council of the Republic of China, Grant No. NSC 86-2115-M-110-014 and NSC 88-2118-M-110-001  相似文献   
115.
A smoothed bootstrap method is presented for the purpose of bandwidth selection in nonparametric hazard rate estimation for iid data. In this context, two new bootstrap bandwidth selectors are established based on the exact expression of the bootstrap version of the mean integrated squared error of some approximations of the kernel hazard rate estimator. This is very useful since Monte Carlo approximation is no longer needed for the implementation of the two bootstrap selectors. A simulation study is carried out in order to show the empirical performance of the new bootstrap bandwidths and to compare them with other existing selectors. The methods are illustrated by applying them to a diabetes data set.  相似文献   
116.
This paper presents a simple and robust method for obtaining a comprehensive understanding of the joint period and radius distribution in Kepler exoplanets. The proposed method is based on particle swarm optimization and bivariate Normal Inverse Gaussian distribution. Furthermore, in the construction of the probability density function, this study selects planet-host stars with the GK-type. The injecting approach is also employed to solve the survey completeness of sample. The resulting occurrence rate of Earth analogs is 0.025 with a 95% bootstrap confidence interval between 0.023 and 0.032.  相似文献   
117.
In this paper, we investigate the k-nearest neighbours (kNN) estimation of nonparametric regression model for strong mixing functional time series data. More precisely, we establish the uniform almost complete convergence rate of the kNN estimator under some mild conditions. Furthermore, a simulation study and an empirical application to the real data analysis of sea surface temperature (SST) are carried out to illustrate the finite sample performances and the usefulness of the kNN approach.  相似文献   
118.
Hedge funds exemplify complex finance in the global economy and are appearing in diverse national settings. One question that follows is whether hedge funds in the Asian region have been localized and exhibit significant differences to their US/UK counterparts or whether there is predominantly one global model. The analysis here point to the importance of what is called replica localization, wherein local control has entailed little deviation from the practices of Anglo-American hedge funds. Evidence generated from databases and interviews confirms the largely equivalent structures and strategies found in the new Asian hedge fund sector. The significance is that a small but growing Asian financial space has been carved out that is funded by Asian capital and managed by Asian elites but matches external models. To further delineate globalized finance, comparative research is needed to determine when and why complex finance is either present or absent outside of Anglo-American economies.  相似文献   
119.
针对相干光正交频分复用(coherent optical orthogonal frequency division multiplexing,CO-OFDM)系统中相位噪声引起的载波间干扰(inter-carrier interference,ICI)问题,提出了一种基于线性预处理的新判决反馈相位噪声抑制算法。该新算法改进了线性预处理部分,利用循环前缀与OFDM符号固有的相关性,在时域进行简单的线性组合运算,充分利用了OFDM符号中冗余信息。仿真分析表明,在激光器线宽为200 kHz且误码率(bit error rate, BER)为10-4时,与判决反馈相位噪声抑制算法和一次迭代的判决反馈相位噪声抑制算法相比,该新算法BER曲线的信噪比(signal to noise ratio,SNR)分别改善了3 dB和1 dB,有效地降低由ICI引起的错误平层。  相似文献   
120.
Sexual abuse has physiological and emotional implications. The purpose of this study is to evaluate the neurobiological sequels of childhood sexual trauma by monitoring physiological variables among sexually abused girls and women compared to controls. We assessed posttrauma and traumatic life events of 35 females sexually abused in their childhood (age range 7–51 years) and 25 control females (age range 7–54 years). Electroencephalography, frontalis electromyography, electrodermal activity, and heart rate parameters were recorded while watching sets of pictures representing neutral and trauma-suggestive stimuli. A minority of participants met the Diagnostic and Statistical Manual of Mental Disorders criteria for post-traumatic stress disorder. Abused females displayed significant elevations in heart rate, electromyography, and electroencephalography while viewing allusive stimuli and elevated heart rate while viewing neutral stimuli. The dysfunctional regulation of the physiological stress system associated with child sexual abuse may endanger the victims with various stress and anxiety disorders.  相似文献   
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