一种改进的电力线通信系统脉冲噪声抑制方法

为了抑制脉冲噪声对电力线正交频分复用（OFDM）通信系统的影响,最常用的方法之一是在接收端OFDM解调器之前前置一个置零非线性单元,即传统置零法。然而,由于引入了非线性失真,其性能并不理想。针对传统置零法引起的非线性失真问题,提出了一种基于迭代消除非线性失真的改进置零法。首先,对接收到的时域OFDM信号进行脉冲噪声检测和置零处理;然后,在频域利用已检测的符号来重构时域置零处理引入的非线性失真,并通过迭代提高重构的准确性;最后,从频域接收信号中减去重构的非线性失真。仿真结果表明,所提改进算法与传统置零法相比,有非常大的性能提升,增强了电力线OFDM通信系统对脉冲噪声的抵抗能力。     

Confirming the timing of phase-based costing in oncology studies: a case example in advanced melanoma

Aims: The utilization of healthcare services and costs among patients with cancer is often estimated by the phase of care: initial, interim, or terminal. Although their durations are often set arbitrarily, we sought to establish data-driven phases of care using joinpoint regression in an advanced melanoma population as a case example.

Methods: A retrospective claims database study was conducted to assess the costs of advanced melanoma from distant metastasis diagnosis to death during January 2010–September 2014. Joinpoint regression analysis was applied to identify the best-fitting points, where statistically significant changes in the trend of average monthly costs occurred. To identify the initial phase, average monthly costs were modeled from metastasis diagnosis to death; and were modeled backward from death to metastasis diagnosis for the terminal phase. Points of monthly cost trend inflection denoted ending and starting points. The months between represented the interim phase.

Results: A total of 1,671 patients with advanced melanoma who died met the eligibility criteria. Initial phase was identified as the 5-month period starting with diagnosis of metastasis, after which there was a sharp, significant decline in monthly cost trend (monthly percent change [MPC]?=?–13.0%; 95% CI?=?–16.9% to –8.8%). Terminal phase was defined as the 5-month period before death (MPC?=?–14.0%; 95% CI?=?–17.6% to –10.2%).

Limitations: The claims-based algorithm may under-estimate patients due to misclassifications, and may over-estimate terminal phase costs because hospital and emergency visits were used as a death proxy. Also, recently approved therapies were not included, which may under-estimate advanced melanoma costs.

Conclusions: In this advanced melanoma population, optimal duration of the initial and terminal phases of care was 5 months immediately after diagnosis of metastasis and before death, respectively. Joinpoint regression can be used to provide data-supported phase of cancer care durations, but should be combined with clinical judgement.     

房地产市场异常现象的行为金融学研究

房地产市场在发展的过程中出现了一些异常现象,传统金融理论面对这些异常现象无法给出令人信服的解释,现以行为金融学的噪声交易理论、反馈机制、羊群效应,对上海房地产市场出现的异常现象进行解释,并在此基础上寻求相应的对策,以促进房地产市场健康发展。     

一种新的2CPFSK信号极化合成方法

针对低信噪比下连续相位调制信号的极化合成,提出了一种基于多符号检测技术的极 化合成新方法。通过把解调和极化合成作为一个整体进行处理,在基带上完成了通常在中频 上实现的极化合成过程,避免了连续相位调制信号在低信噪比下载波相位跟踪困难的问题。 仿真结果表明,该方法的合成效果与理论值之间的差距小于0.3 dB。     

Investor Sentiment and Stock Market Volatility: Evidence from India

In this article, the authors probe the role of irrational investor sentiment in the determination of Indian stock market volatility. The authors developed a new irrational aggregate sentiment index (IASI) to examine the issue. The conditional volatility is extracted from the nonlinear univariate models for the market indices and the IASI. The vector autoregression (VAR) is carried out to analyze the relationship between the volatility of irrational aggregate sentiment index and stock market volatility. The authors find a unidirectional causality from sentiment to stock market volatility, and their findings highlight the significance of sentiment in explaining the stock market volatility in India.     

会计信息的数据挖掘方法与银行信贷风险预测

基于信息熵理论和数据挖掘技术,提出一种会计信息的数据挖掘方法,投资者和债权人可用这种方法从企业的会计数据中挖掘决策信息,并以银行信贷风险预测模型构建为例,对这种方法的有效性进行了实证检验。     

雷达接收机噪声特性研究分析

噪声是影响接雷达收机灵敏度的主要因素。接收机噪声越小,灵敏度就越高,所能够接收的信号就越弱,雷达的作用距离也就越远。本文首先对雷达接收机噪声进行分析,给出雷达接收机噪声系数与噪声温度的关系,最后提出了几种降低接收机噪声的具体方法。     

工程项目施工阶段的工程造价控制策略研究

本文首先阐述了工程造价的基础理论知识及工程造价管理流程;然后就YN工程实例分析了该工程项目施工阶段工程造价控制中存在的问题;最后针对这些问题提出了施工阶段工程造价控制的策略。     

工程各阶段造价控制目标体系构建与控制措施

伴随着我国不断深入的经济改革,国民经济出现了迅速发展的趋势,我国每年投资固定资产上的资金在不断累加,我国经济发展中起到了重要支撑作用的就是建筑业。目前,我国对工程各阶段造价控制进行了进一步的研究,并且对其积极推广应用,可是同世界发达国家之间依然存在着一定的距离。造价控制方法方面依然缺乏一定的配合能力。因此,我国应不断加快工程造价控制管理,提升建筑行业的竞争能力,最大程度的节省社会资源。本文以工程各阶段造价控制目标体系构建与控制为例,分析了工程各阶段造价控制管理意义,工程各阶段造价控制目标的构建,工程各阶段造价控制目标措施。     

铁岭市老城区环境噪声适用区域应重新划分的研究

铁岭市老城区用地规划已发生很大变化,现行的《铁岭市城区环境噪声适用区域划分方案》已不适用,按照《城市区域环境噪声适用区划分技术规范》重新划分铁岭市老城区环境噪声适用区域,对比现行的《铁岭市城区环境噪声适用区域划分方案》,分析重新划分的必要性。