LFMCW雷达信号多周期模糊函数分析

给出了LFMCW雷达信号的多周期模糊函数,并与单周期信号进行了比较。讨论了在单周期和多周期的模糊函数联系,沿主轴切割模糊函数的性质和体积有限方面上两者特征的差别。仿真结果表明,增大周期可提高多普勒分辩力,但不能改善时延分辩力。     

Setting Priorities in Behavioral Interventions: An Application to Reducing Phishing Risk

Phishing risk is a growing area of concern for corporations, governments, and individuals. Given the evidence that users vary widely in their vulnerability to phishing attacks, we demonstrate an approach for assessing the benefits and costs of interventions that target the most vulnerable users. Our approach uses Monte Carlo simulation to (1) identify which users were most vulnerable, in signal detection theory terms; (2) assess the proportion of system‐level risk attributable to the most vulnerable users; (3) estimate the monetary benefit and cost of behavioral interventions targeting different vulnerability levels; and (4) evaluate the sensitivity of these results to whether the attacks involve random or spear phishing. Using parameter estimates from previous research, we find that the most vulnerable users were less cautious and less able to distinguish between phishing and legitimate emails (positive response bias and low sensitivity, in signal detection theory terms). They also accounted for a large share of phishing risk for both random and spear phishing attacks. Under these conditions, our analysis estimates much greater net benefit for behavioral interventions that target these vulnerable users. Within the range of the model's assumptions, there was generally net benefit even for the least vulnerable users. However, the differences in the return on investment for interventions with users with different degrees of vulnerability indicate the importance of measuring that performance, and letting it guide interventions. This study suggests that interventions to reduce response bias, rather than to increase sensitivity, have greater net benefit.     

Spatial prediction of crystalline defects observed in molecular dynamic simulations of plastic damage

Molecular dynamic computer simulation is an essential tool in materials science to study atomic properties of materials in extreme environments and guide development of new materials. We propose a statistical analysis to emulate simulation output with the ultimate goal of efficiently approximating the computationally intensive simulation. We compare several spatial regression approaches including conditional autoregression (CAR), discrete wavelets transform (DWT), and principle components analysis (PCA). The methods are applied to simulation of copper atoms with twin wall and dislocation loop defects, under varying tilt tension angles. We find that CAR and DWT yield accurate results but fail to capture extreme defects, yet PCA better captures defect structure.     

就业市场文凭贬值的经济学分析

本文运用经济学有关原理对现在就业市场上的文凭贬值现象作了简要分析,指出文凭贬值现象的背后是就业市场的信号在一定程度上的失灵,对失灵的原因作了分析,并提出一些改善就业市场状况的建议。     

我国上市公司股利政策：现实选择与理论诠释

作为公司财务理论的核心内容之一,股利政策是公司在利润再投资与回报投资者两者之间的一种权衡。我国上市公司的股利政策具有不分配现象仍然普遍、股利形式规律性不强、股利政策缺乏稳定性和连续性等特征,导致最有说服力的信号理论和代理理论也难以解释我国上市公司的股利政策。针对这一问题,建议拓宽融资渠道,缩小不同融资方式的成本差异;完善法律法规,规范股利分配的信息披露制度;降低代理成本,保持持续稳定的现金股利政策;改善治理结构,建立健全小股东利益保护机制。     

《刑事诉讼法学》课程多元化、实践性教学模式探讨

《刑事诉讼法学》课程的教学应适应21世纪对法学本科教育目标的要求,即将学生培养成为“法律知识、技术、观念和信仰的有机统一的法律人”之目标努力。因此,改变传统的单一式教学模式势在必行。我们认为应采用多元化教学内容,多元化教学方式,注重实践性教学环节的教学模式施教,方可实现上述目标。     

论自然直观的异质性与哲学中立化——异质性理论的预备性探讨

针对先前哲学在直观问题上的种种弊端,本文将人的意识世界另行划分为自然直观和符号指谓。自然直观是通过感官对对象的直接"意识到",与符号无涉。这是一种自然的意识形式,其机能是自然赋予的,它保证了人同周遭世界即时感应的互动性协调。符号指谓是通过人所发明的符号之间的连接去指谓对象所实现的间接"意识到",它是人工的意识形式,是人创造属人生活之所需。符号指谓包括概念思维,哲学是概念思维的最抽象形式。通过异质性理论的哲学分析可以发现,自然直观包含了大量异质性。异质性就是种类间的不可通约性。自然直观的神奇之处在于,它能将哲学所分析到的异质性因素整合得天衣无缝。相比之下,包括哲学在内的概念解释则必须接受逻辑约束,只能操作同质性。因此,自然直观既无须哲学为自己奠基,也不可能充当任何特定哲学理论的基础;哲学的本分在于解决符号世界,特别是概念领域的问题。     

双调谐回路负阻放大器的最大平坦特性

在微波放大器的谐振腔中引入双调谐腔回路是实现宽带微波及毫米波负阻放大器的有效方法。在推导出了该电路的稳态工作方程之后,着重讨论了实现最大平坦增益特性的条件,指出两谐振腔负载Q值的比值是实现最大平坦增益的决定因素,导出了获得最大平坦增益时,电路参数的解析表达式,从而为最大平坦增益设计提供了理论依据,研究的理论得到了以往文献中实验结果的验证。     

铁氧体全极化器信号流图分析

应用信号流图分析了 3种不同组合全极化器 ,同时考虑 2个铁氧体杆之间的反射 .尽管反射系数和损耗都是小量 ,但精确圆极化仍无法得到 .