Outage Performance Analysis of NOMA in Wireless Powered Cognitive Radio Networks with AF and DF Relaying Techniques

Improving spectral efficiency under a certain energy limitation is an important design metric for future wireless communications as a response to the growing transmission demand of wireless devices. In order to improve spectral efficiency for communication systems without increasing energy consumption, this paper considers a non-orthogonal multiple access (NOMA)–based cognitive radio network, with the assistance of a wireless-powered relay station (RS), and then analyzes the system outage performance under amplified-and-forward (AF) and decoded-and-forward (DF) cooperative transmission modes. Specifically, the base station (BS) has the opportunity to cooperate by transmitting information through the RS, depending on whether the RS can harvest sufficient RF energy for cooperative transmission. That is to say, when the energy stored by the RS is sufficient for cooperative transmission, the RS will assist the BS to forward information; otherwise, the BS will send information through direct links, while the RS converts the radio frequency (RF) signals sent by the BS into energy for future transmission. Moreover, the transmission power required by the RS for cooperative transmission is usually relatively large, while the amount of harvested energy by the RS in a transmission slot is usually low, so it takes several consecutive time slots to accumulate enough transmission energy. To this end, we utilize a discrete-time Markov chain to describe the processes of charging and discharging of the RS. Subsequently, we derive the closed-form outage probabilities of both the primary and secondary systems for the considered system in AF and DF modes through mathematical analysis, and verify the accuracy of the analyses through Monte Carlo simulation. The simulation results show that the two proposed cooperative transmission schemes with AF and DF relaying techniques outperform both direct transmission and other similar schemes in both the primary and secondary system, while the DF scheme can provide better performance than the AF scheme within the range of setting values.     

Catastrophe Theory Applied to Neuropsychological Data: Nonlinear Effects of Depression on Financial Capacity in Amnestic Mild Cognitive Impairment and Dementia

Financial incapacity is one of the cognitive deficits observed in amnestic mild cognitive impairment and dementia, while the combined interference of depression remains unexplored. The objective of this research is to investigate and propose a nonlinear model that explains empirical data better than ordinary linear ones and elucidates the role of depression. Four hundred eighteen (418) participants with a diagnosis of amnestic MCI with varying levels of depression were examined with the Geriatric Depression Scale (GDS-15), the Functional Rating Scale for Symptoms of Dementia (FRSSD), and the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS). Cusp catastrophe analysis was applied to the data, which suggested that the nonlinear model was superior to the linear and logistic alternatives, demonstrating depression contributes to a bifurcation effect. Depressive symptomatology induces nonlinear effects, that is, beyond a threshold value sudden decline in financial capacity is observed. Implications for theory and practice are discussed.     

司法公正的象征建构：在认知与规范之间

在以和谐与稳定为主的社会环境下,实用主义司法哲学强调的是一种结果导向的利益衡量方法。这种基于利益认同而塑造的公正幻象注定只能在利益相关方的认知期望之间形成短暂的共识,无法提供制度化的张力。在“终极价值个人化”的格局下,甚至还有可能形成获益者“端起碗来吃肉,放下筷子骂娘”的制度认同困境。从稳定社会期望的角度来看,“马锡五审判方式”最可称道之处在于其自发地建构出一种“把第三方置于期望担保人位置的机制”。这样一来,对符合规范之行为的期望,以及对这一期望的期望就不仅仅来自在场的利益相关人,而且也来自与实际争议利益无涉但是却有“代入感”的第三方及其背后象征的社会期望。由此,与实际上能够达成的有限共识相比,具有稳定性的期望得以建立。得益于第三方期望的制度化,在正常情况下我们就不会对制度公正的假定产生质疑。     

雷达信号环境测量系统的设计与测试

针对复杂电磁环境特性认知与可视化的现实应用需求,设计了一套基于分层认知概念的雷达信号环境测量系统,实现了对外界多个雷达辐射源信号参数的感知测量,同时以二维坐标形式对测量过程中的各种物理量进行了分层可视化展示。该系统的设计实现期望能够为电磁环境感知、分析提供一种有效的技术方案参考。     

Improving understanding,learning, and performances of novices in dynamic managerial simulation games

Simulations are increasingly used in training and education because of their success and their advantages as a learning method. However, it has also been observed that the dynamic complexity of simulations creates learning difficulties, and that performance tends to plateau quickly at a level well below benchmark performance. To overcome this difficulty, a gradual‐increase‐in‐complexity approach is proposed, which suggests developing simpler versions of a simulation game that can be used as part of the training. Accordingly, the authors developed a series of inventory‐management simulations and conducted an experiment. The results indicate an improvement in the success of the inventory‐management simulation as a training tool. © 2009 Wiley Periodicals, Inc. Complexity, 2010     

Toward scale‐free like behavior under increasing cognitive load

To understand how cognition and response selection processes might emerge from dynamic brain systems, we analyzed reaction times during the performance of both a working memory task and a choice reaction time task at different levels of “cognitive load.” Our findings suggest a continuous transition—tuned by load—from random behavior toward scale‐free like behavior as an expanding connectivity process in a network poised near a critical point. © 2012 Wiley Periodicals, Inc. Complexity, 2012     

基于教学主题蕴含的素养发展价值设计化学教学——依据限定条件书写同分异构体

分析同分异构体(同分异构现象)的素养发展特质,抽提认识有机物分子结构多样性的认识视角。引导学生基于“同分异构现象”“限定条件”建构认知模型,在不同水平认识有机物分子结构的多样性。     

基于微粒与类别的“碳酸钠与碳酸氢钠”的教学

利用Na₂CO₃和NaHCO₃在生活中的应用,创设情境认识它们性质上的差异,基于Na₂CO₃化学性质的已有认知,开展对NaHCO₃化学性质的预测和实验验证活动,引导学生构建从组成微粒和物质类别视角分析研究物质性质的思路和方法,注重学生逻辑推理能力的发展,凸显核心观念对元素化合物学习的指导功能,使知识向素养转化。     

基于化学学科理解的电化学主题认识模型研究*

在核心素养导向的化学教学实践新时代背景下,基于化学学科理解构建相应主题的认识模型,提升教师的化学学科理解水平,进而开展素养为本的课堂教学促进教师专业发展,为化学教育理论和实践研究提供了重要的思路和方向。以电化学主题为例,基于化学学科理解构建其认识模型,以期其研究思路和过程对化学学科其他主题的理论和教学研究具有启示作用。     

基于规则空间模型的化学学习诊断分析

采用规则空间模型诊断学生的认知情况,改变了测验只是报告测验分数的做法,拓展了教育评价的诊断功能。以初中化学学习难度较大的"物质组成的表示"为例进行了实证研究,在对所要考查的属性进行梳理的基础上编制测验项目,运用规则空间模型将所有被试划归为不同的反应模式,从而分析学生的认知状态,诊断出学生的认知缺陷,并为教师教学提供建议。