开关电源电磁干扰与抑制方法

对开关电源中电磁干扰的产生机理做了简要的描述,并提出了几种抑制电磁干扰的措施:通过减小干扰源产生的干扰信号,切断干扰信号的传播途径,增强受干扰体的抗干扰能力。上述措施取得了良好效果,可有效提高开关电源的电磁兼容性。     

青春发育突增期不同发育类型学生的性发育、性教育状况及其干预

对北京市海淀区五所中学中1987年9月至1988年8月出生的男生457和三所小学中1989年9月至1990年8月出生的女生450人拍摄了X射线骨龄片,并请专家按CHN法对每张骨龄片进行了判别,从中筛选出了男、女生早发育组、正常发育组、晚发育组每组30人,共计180人作为实验对象,对实验对象的第二性征进行了测试并对其性知识和态度等进行了问卷调查,较好的了解了目前青春发育突增期三种发育类型学生的性发育状况及其对性知识和性教育的态度,较深入地分析了目前我国性教育中存在的问题,为今后更好的对青春发育期的学生进行性教育提供了理论依据.     

基于干涉图加权叠加的图像压缩算法

在对图像进行压缩的过程中,容易出现信息丢失的情况,导致传统图像压缩算法由于相关性低的图像也可参与等权计算,使得图像产生偏差及失真,无法有效实现图像压缩,提出一种基于干涉图加权叠加的图像压缩算法,给出高相关点的平均形变相位变化速率,依据误差传播定律,求出全部干涉图叠加后高相关点受到的大气延迟干扰,对每个图像对应的相关系数进行计算,依据模型采集高相关目标点,干涉图被叠加后,给出高相关点大气延迟对线性形变速率的干扰,通过移位操作获取样本的Exp-Golomb级数,完成编码获取数据的非负映射操作,利用上一个样本的Exp-Golomb编码级数对当前样本值级数进行估测,通过计算原始干涉图数据和压缩后的干涉图数据的压缩比与峰值信噪比,对压缩效果进行度量。通过光谱相对均方误差RQE对压缩前后的原始光谱和复原光谱进行度量。仿真实验结果表明,所提方法具有很高的精度。     

知识员工角色压力对生活满意度的影响研究—一个被调节的中介效应模型

基于对528名知识员工的两阶段调查,探讨了角色压力对生活满意度的影响、家庭干涉工作的中介作用以及社会支持的调节作用。层次回归与调节路径分析结果表明:知识员工角色压力对其生活满意度不仅可以产生直接消极影响,而且当社会支持较低时,还会通过家庭干涉工作的完全中介作用产生间接消极影响;该作用机制具体表现为被调节的中介效应,即家庭干涉工作在角色压力与生活满意度之间的中介作用受到社会支持的负向调节,在较高社会支持水平下,家庭干涉工作对生活满意度的影响将不再显著,并且角色压力也不再通过家庭干涉工作的中介作用对生活满意度产生间接影响。     

基于干扰协调的公平性与吞吐量均衡算法

文章研究了下一代移动通信系统资源分配中的小区边缘用户数据流量与小区总吞吐量之间的折中均衡方案.采用干扰协调技术及功率控制算法,引入小区公平性因子来均衡频谱利用率和系统公平性.仿真计算结果显示,与传统PF算法相比,改进算法(TFI-PF)可以有效改善系统性能,提高小区吞吐量水平并改善用户公平性,在频谱利用率和公平性之间进行良好的均衡折中.     

MIMO-OFDM 系统中同信道干扰抑制

针对 MIMO-OFDM 系统,提出了一种最大后验概率的信道矩阵和干扰协方差矩阵估计方法,并设计了迭代求解算法。利用所估计的信道矩阵和干扰协方差矩阵,采用 IRC 接收机完成同信道干扰的抑制。利用干扰协方差阵的共轭对称与半正定等特性,提出2种干扰协方差矩阵的处理方案以提高其估计精度。第1种方案将每个子载波上干扰协方差矩阵表征为一系列时域矩阵之和,第2种方案将每个子载波上的干扰协方差矩阵用低阶模型来建模,其中模型阶数通过最小描述长度算法估计。仿真结果表明了所提方案的有效性。     

对劈形薄膜等厚干涉的光程差及条纹定域性的讨论

物理和科学的发展使得薄膜干涉的应用越来越广泛。但是,目前对于等厚干涉的光程差一级条纹定域问题的分析并不多。本文基于等厚干涉的原理以及光程差同条纹定域之间的联系,分别对光程差以及条纹定域进行讨论。     

网络动态干扰监控的信任感知推荐算法设计

网络用户信任感知推荐的准确性设计是提高用户间的社交网络辅助信息信任度的重要依据。传统的网络用户信任感知推荐算法采用的是基于社交网络服务和用户评分的推荐系统,主观性较大,协同过滤效果不好。提出一种基于网络动态干扰监控的信任感知推荐算法设计新方法,设计自适应神经模糊系统网络动态干扰监测算法,构建基于向量空间模型的信任度评价指标体系结构,通过调整网络拓扑权重向量设置信任度周期响应加权变量自适应函数,有效降低迭代算法的运算成本,避免了自适应神经模糊系统网络动态干扰监测加权权重成固化状态,提高抗干扰性能。实验结果表明,算法能使社交网络感知推荐模型的预测误差减少,推荐可靠性优于传统方法。     

History of the preanalytical phase: a personal view

In the 70ies of the last century, ther term “preanalytical phase” was introduced in the literature. This term describes all actions and aspects of the “brain to brain circle” of the medical laboratory diagnostic procedure happening before the analytical phase. The author describes his personal experiences in the early seventies and the following history of increasing awareness of this phase as the main cause of “laboratory errors”. This includes the definitions of influence and interference factors as well as the first publications in book, internet, CD-Rom and recent App form over the past 40 years. In addition, a short summary of previous developments as prerequesits of laboratory diagnostic actions is described from the middle age matula for urine collection to the blood collection tubes, anticoagulants and centrifuges. The short review gives a personal view on the possible causes of missing awareness of preanalytical causes of error and future aspects of new techniques in regulation of requests to introduction of quality assurance programs for preanalytical factors.     

Interference of medical contrast media on laboratory testing

The use of contrast media such as organic iodine molecules and gadolinium contrast agents is commonplace in diagnostic imaging. Although there is widespread perception that side effects and drug interactions may be the leading problems caused by these compounds, various degrees of interference with some laboratory tests have been clearly demonstrated. Overall, the described interference for iodinate contrast media include inappropriate gel barrier formation in blood tubes, the appearance of abnormal peaks in capillary zone electrophoresis of serum proteins, and a positive bias in assessment of cardiac troponin I with one immunoassay. The interference for gadolinium contrast agents include negative bias in calcium assessment with ortho-cresolphthalein colorimetric assays and occasional positive bias using some Arsenazo reagents, negative bias in measurement of angiotensin converting enzyme (ACE) and zinc (colorimetric assay), as well as positive bias in creatinine (Jaffe reaction), total iron binding capacity (TIBC, ferrozine method), magnesium (calmagite reagent) and selenium (mass spectrometry) measurement. Interference has also been reported in assessment of serum indices, pulse oximetry and methaemoglobin in samples of patients receiving Patent Blue V. Under several circumstances the interference was absent from manufacturer-supplied information and limited to certain type of reagents and/or analytes, so that local verification may be advisable to establish whether or not the test in use may be biased. Since the elimination half-life of these compounds is typically lower than 2 h, blood collection after this period may be a safer alternative in patients who have received contrast media for diagnostic purposes.