基于AD9361的掌上型LTE RRU设计与开发

当前小体积远端射频单元（Remote Radio Unit,RRU）主要是皮站级别的Pico-RRU，其重量和体积仍然难以满足掌上型的要求。为此，采用高集成度的AD9361芯片来实现长期演进（Long Term Evolution，LTE）宽带收发信机功能，配合时钟同步模块、放大器模块和控制接口电路等一起构建低成本的掌上型RRU。主要解决了基于AD9516的时钟同步、低相位噪声设计和高灵敏度接收机设计三个技术难点，成功实现了掌上型、高性能、低成本的设计目标。整个RRU样机尺寸为18 cm×10 cm×2 cm，质量约500 g，量产成本千元以内。测试表明，该RRU下行误差向量幅度（Error Vector Magnitude，EVM）小于3%，优于3GPP要求的8%；10 MHz带宽时上行接收机灵敏度优于3GPP要求的-93.5 dBm。     

长三角区域行政发展思路的分析与评价

当前,长三角区域经济、社会快速健康发展,形势喜人。但长三角区域行政体制僵化,运作缓慢,效率低下,阻碍了区域经济社会的进一步发展。关于长三角区域的发展,学术界、政府部门和民间有不同的看法,笔者就长三角区域行政的发展思路作个分析与评价,以加深对这个问题的研究。     

长三角居民赴韩旅游消费模式初探

在实证研究的基础上从出游认知、消费构成、消费评价和消费趋势进行分析，探讨了长三角地区居民赴韩旅游消费模式。研究表明，长三角地区居民赴韩旅游出游认知和消费构成亦处于初级阶段，对消费评价和消费倾向大体上持肯定态度和乐观态度。     

公共行政的范式转换及其政府信任问题

政府信任是政府和公众之间基于公共利益的博弈互动关系．符合公共利益的行政价值理念将为政府提供持久的、合法的信任源泉。从官僚制到新公共管理，由于片面注重管理主义工具价值，而忽视公共利益和民主价值，不可避免地面临着政府信任的困境。民主行政作为新公共行政的学术识别系统。坚持和发展公共利益价值取向，实现价值理性和工具理性的统一，符合人类理性与社会公共利益均衡健康发展的内在需要。必然会全新构建和强化公众与政府的互信合作关系。     

Testing of unit roots and other fractionally integrated hypotheses in the presence of structural breaks

Tests of unit roots and other nonstationary hypotheses that were proposed by Robinson (1994) are applied in this article to the Nelson and Plosser's (1982) series. The tests can be expressed in a way allowing for structural breaks under both the null and the alternative hypotheses. When applying the tests to the same dataset as in Perron (1989), we observe that our results might be consistent with those in Perron (1989) when testing the nulls of trend-stationarity or a unit-root. However, we also observe that fractionally integrated hypotheses may be plausible alternatives in the context of structural breaks at a known period of time. Final version received: August 2000/Final version accepted: August 2001 RID="*" ID="*"  The author gratefully acknowledges the financial support from the European TMR grant No. ERBFMRX-CT-98-0213. Comments of two anonymous referees are also acknowledged.     

Long memory in volatilities of German stock returns

We show that there is strong evidence of long-range dependence in the volatilities of several German stock returns. This will be done by applying a method using the difference of the classical log-periodogram regression estimator for the memory parameter and of the tapered periodogram based estimator. Both estimators give similar values for the memory parameter for each series and this indicates long memory. To support our findings we apply also a methodology using the sample variance and a wavelet based estimator to the data. Also these two methods show clear evidence of long-range dependence in the volatilities of German stock returns.First version received: December 2001/Final version received: March 2003The computational assistance of Eleni Mitropoulou and Björn Stollenwerck as well as the helpful comments of two unknown referees are gratefully acknowledged. Research supported by Deutsche Forschungsgemeinschaft under SFB 475. Stock returns were obtained from Deutsche Finanzdatenbank (DFDB), Karlsruhe.     

On a clear day you might see an environmental Kuznets curve

We shed some new light on the Environmental Kuznets curve (EKC) and show how it can be viewed as a particular form of equilibrium relationship, where technology and preference parameters determine the shape of the curve. In contrast to most of the literature on the EKC, we estimate a theoretically consistent model on long-run data (Swedish sulfur emission, covering the period 1900–2002). Furthermore, we test and date structural change. The model suggests four regimes, 1900–1918, 1919–1933, 1934–1967 and 1968–2002, generating four rather different patterns for pollution over time. The policy-conclusions are consonant with Pearce’s general view about the EKC: there is no theoretical presumption that it has an inverted U shape, nor should any country try to “grow out of the environmental problems” without analyzing the benefits and costs of so doing.     

一种非市场因素导致的铁矿石价格上涨——基于博弈的分析

通过一个可重复博弈模型,揭示了中国在国际铁矿石贸易中面临由非市场因素造成的价格上涨问题,认为,造成这种现象的根本原因是中国在铁矿石贸易中的市场地位并没有随着进口量的提高而提高,并从资源安全角度提出了应对策略。     

Another look at long memory in common stock returns

We apply the modified rescaled range test to the return series of 1,952 common stocks. The results indicate that long memory is not a widespread characteristic of these stocks. But logit models of the event of a test rejection reveal that rejections are linked to firms with large risk-adjusted average returns. The maximal moment of a return distribution is also found to influence the event of a rejection, but not in a way suggestive of moment-condition failure. Evidence suggestive of survivorship bias is also uncovered. We conclude that there is some evidence consistent with persistent long memory in the returns of a small proportion of stocks.     

上市公司“MD&A”信息质量评价模型——基于政府监管的视角

管理层讨论与分析(Management’s Discussion and Analysis,MDA)作为财务报表的有益补充,因其能够有助于增强信息披露的针对性和有效性而越来越受到信息使用者的关注。针对我国MDA信息质量不高的现状和评价体系不尽完善的情况,总结和吸收前人的研究成果,合理界定MDA信息质量特征。在此基础上,充分考虑MDA信息的生成机制和外部评价结果,采用层次分析法,构建适合我国上市公司MDA信息质量评价模型。