对西部地区承接产业转移中的生态伦理问题若干思考——以广西壮族自治区承接东部产业转移为例

生态与经济协调发展是当今国际社会普遍关注的重大问题,本文拟从生态伦理学的角度出发,以广西壮族自治区为例,分析西部地区在承接东部产业转移过程中出现的生态伦理问题,并提出建设性的意见,借以引起人们对生态伦理问题的关注,进一步推进科学发展观的全面落实,建设更加和谐美好的大西部。     

叠加共轭对称训练序列的OFDM系统时频同步方法

针对正交频分复用（OFDM）系统对同步错误率和频率偏移敏感的问题,提出了一种叠加共轭对称训练序列的OFDM系统时间和频率同步方法。该同步方法将快速傅里叶逆变换（IFFT）调制后的序列构成具有共轭对称特性的训练序列,并叠加到OFDM数据符号上;在接收端,利用叠加训练序列和融合循环前缀信息来获取OFDM系统同步信息。理论分析和仿真表明：在信噪比为5 dB时,该同步算法定时同步正确概率已接近100%;在信噪比为4 dB时,频偏估计精度可以达到10-4;该同步算法不仅具有更好的同步性能,而且节省系统的有效带宽以及降低系统的计算法复杂度。     

基于多项式拟合频率重构的物理不可克隆函数优化

近年来硬件安全不断受到挑战,具有不可预测性、随机性等特性的环形振荡器物理不可克隆函数（Ring Oscillator Physical Unclonable Function,RO PUF）可作为硬件安全重要的加密密钥方式,但通常原始RO PUF不满足加密密钥对随机性的要求。因此,提出了基于多项式拟合频率重构的PUF优化方法。首先,实现RO电路的硬宏设计并在现场可编程门阵列(Field Programmable Gate Array,FPGA)上进行实例化,从而获得RO阵列的频率数据;其次,针对原始响应的随机性较差的情况,通过统计分析其分布特征,利用多项式拟合法优化重构RO阵列频率;最后,采用熵密度值评估RO PUF响应的随机性。选用型号为Xilinx Artix 7103的FPGA板进行实验测试评估,结果表明所提方法不仅比原始RO PUF响应的随机性强,而且与随机补丁混合法(Random Patch Mixer,RPM)和基于回归的熵蒸馏法相比也具备更好的随机性。     

变革前消极非正式信息对员工的影响机制研究

组织变革前会有相关的非正式信息,这些信息影响员工对变革的认识。文章探索变革前消极非正式信息量对员工变革抵制意愿的影响,以及员工变革抵制意愿随时间推移的变化,信息频率与尽责性对员工变革抵制意愿变化的调节作用。基于159位员工调查数据的多层次线性增长模型分析表明：消极非正式信息量显著增加员工的变革抵制意愿,但这种抵制意愿随时间推移而显著衰减;消极非正式信息频率与尽责性对员工变革抵制意愿随时间衰减有三维调节作用：在低信息频率下,低尽责性员工的变革抵制意愿随时间衰减更快。研究结果对组织变革有一定理论和实践意义。     

The endo–exo problem in high frequency financial price fluctuations and rejecting criticality

The endo–exo problem lies at the heart of statistical identification in many fields of science, and is often plagued by spurious strong-and-long memory due to improper treatment of trends, shocks and shifts in the data. A class of models that has shown to be useful in discerning exogenous and endogenous activity is the Hawkes process. This class of point processes has enjoyed great recent popularity and rapid development within the quantitative finance literature, with particular focus on the study of market microstructure and high frequency price fluctuations. We show that there are important lessons from older fields like time series and econometrics that should also be applied in financial point process modelling. In particular, we emphasize the importance of appropriately treating trends and shocks for the identification of the strength and length of memory in the system. We exploit the powerful Expectation Maximization algorithm and objective statistical criteria (BIC) to select the flexibility of the deterministic background intensity. With these methods, we strongly reject the hypothesis that the considered financial markets are critical at univariate and bivariate microstructural levels.     

Are REITs more resilient than non-REITs? Evidence from natural experiments

REITs draw attention from investors around the world, yet our understanding of the various risks associated with such securities is limited. Using the introduction of Arrowhead, a low-latency high-frequency trading platform, to the Tokyo Stock Exchange and the financial crisis of 2008 as natural experiments, we compare the resilience of REITs and equities in terms of liquidity and volatility. The results indicate that the introduction of Arrowhead improved the quality of the Japanese REIT market but also increased the probability of flash crashes. We also find that although the financial crisis significantly deteriorated overall equity market quality, the Japanese REIT market was resilient. Finally, using a difference-in-differences regression model, we show that the higher transparency and better price discovery of REITs, compared to non-REITS, protected them from the negative effects of the financial crisis and the introduction of Arrowhead. Overall, our analysis shows that REITs are more resilient than non-REITs.     

Time and frequency domain causality Testing: The causal linkage between FDI and economic risk for the case of Turkey

This study aims to explore the causal relationship between economic risk and foreign direct investment (FDI) inflows for the case of Turkey. With the aim of establishing robust findings for the research in mind, both traditional and modern causality techniques are utilized; time domain Granger (1969, “Investigating Causal Relations by Econometric Models and Cross-Spectral Methods.” Econometrica 37: 424–438.), Toda and Yamamoto (1995, “Statistical Inference in Vector Autoregressions with Possibly Integrated Processes.” Journal of Econometrics 66 (1–2): 225–250.), Fourier Toda-Yamamoto and frequency domain Breitung and Candelon (2006, “Testing for short- and long-run causality: A frequency-domain approach.” Journal of Econometrics 132 (2): 363–378.) spectral causality test. Our empirical findings reveal that; economic risk changes in Turkey significantly lead to changes in FDI inflows. However, there is no evidence of causality running from FDI to economic risk. The findings imply that economic risk is an essential determinant of FDI inflows in Turkey. Our findings are compatible with historical macroeconomic developments in Turkey and imply important policy implications. The results of this study can be generalized for other emerging economies that have similar macroeconomic environments, in order to create useful policy implications regarding FDI inflow.     

Systemic circular business model application at the company,supply chain and society levels—A view into circular economy native and adopter companies

This study contributes to the conceptualization of a sustainable circular business model (CBM), the application of the circular economy (CE) by companies. The study utilized a three-level framework adapted from the CE literature with company (micro), supply chain (meso) and society (macro) levels. This multiple-case study in the textile industry included two types of companies operating in the CE: companies founded on the sustainable principles of a CE (natives) and companies transitioning to a CE from the linear economy (adopters). The findings show that the adopters emphasized long-term economic sustainability on a company level and implemented CE elements to varying degrees on all three levels. The natives pursued business decisions from environmental and social sustainability standpoints, and the three levels were integral in their systemic approach to a CE. The study highlights two key claims: established operational structures and economic volition hindered adopters in their systemic CE implementation, and an integral part of the CBM for natives was a proactive approach towards the society level.     

双离合自动变速器电控电动换挡执行机构仿真优化与试验对比

为了提高双离合变速器在车辆上的换挡品质,提升电气化换挡执行机构的工作效率,给出执行机构性能与换挡品质评价准则;通过两种不同双离合变速器电控电动执行机构的工作原理与性能分析,基于MATLAB数值仿真方法优化出最高效率进行试验.基于车辆6个维度的换挡工况对二者所搭载的变速器分别进行试验与CAN线数据采集,对比研究两种机构优缺点,通过雷达图的方式进行优劣说明.结果表明,两种执行机构传动效率可达70％且换挡品质相当.可见Tip in tip out工况对二者要求最为严格.