刘江黄河大桥主桥运行环境下的振动测试

本文通过对刘江黄河大桥主桥运行环境下的振动实测,得到桥梁的在不同频率下的竖向加速度、横向加速度的响应振动稳定图,扭转振型及扭转频率,判断吊杆的损伤对横、竖向振动的影响,推知桥梁目前的运行状态。     

施工升降机齿轮锥鼓形渐进式防坠安全器检验方法的研究

针对施工升降机防坠安全器的检验状况,阐述了检验项目和手段,通过搭建防坠安全器检验实验平台,将检验项目如制动性能试验、安全器制动距离、齿轮转动轻便灵活性试验等逐一在检验平台上完成,并通过采集软件获得有效检验数据,对数据进行归纳、总结分析得出检验结论,最终形成一套完整的检验防坠安全器的方法。人机工作原理的专用操作控制台将各种仪器、电脑及显示器,控制器与操作按钮等布置在同一操作台内,紧凑,实用,美观,可以满足各种安全器检测的需要,整个检测过程不需人工干预,实现检测过程自动化,为今后全面开展防坠安全器的检验业务提供了技术支持。     

Patience and achievement test results

I investigate the relation between high-stakes achievement test scores and students’ patience. I use an experimentally validated measure of time preferences to assess patience in a large sample of Dutch students in secondary school. A one SD increase in the achievement test at the age of 12 predicts 26% of an SD greater level of patience at the age of 15. The results hint at the fact that education can shape preferences.     

An econometric analysis of global warming hiatus

There is an avid debate concerning the presence of a hiatus in global warming. Recognizing that this phenomenon has considerable economic implications, this study aims to make a threefold contribution to the climate econometrics literature. Firstly, it formulates a testable hypothesis; secondly, it proposes a systematic empirical procedure; thirdly, it performs the Bai–Perron test to detect the starting point of the global warming hiatus. The findings supported the existence of the global warming hiatus.     

李沟井田二_1煤层可选性评价

在分析了李沟井田煤层煤质特征的基础上,利用筛分试验和浮沉试验研究了该井田二1煤层的可选性。研究结果表明,二1煤层的自然粒度13~0.5mm粒级的占62.30~75.96%,平均68.18%;当二1煤层浮煤灰分为10%时,其可选性等级为难选—极难选;当二1煤层浮煤灰分为13%时,其井田大部分地段可选性等级易选,局部为极难选。     

Testing the validity of PPP theory for African countries

This study examines the purchasing power parity theory for 14 African countries by applying a recent composite time series method that incorporates the Fourier approximation. The structural breaks are modelled as a gradual smooth process by means of a Fourier component. The Fourier unit root test failed to find any evidence showing that real exchange rates for these 14 countries have mean-reverting tendencies. However, both cointegration and Fourier cointegration tests detect a stable long-term relation between the nominal exchange rate and relative price levels for 8 out of 14 countries; moreover, for five countries Fourier component in cointegration analysis is found to suit quite well.     

The geometry of distributional preferences and a non-parametric identification approach: The Equality Equivalence Test

This paper proposes a geometric delineation of distributional preference types and a non-parametric approach for their identification in a two-person context. It starts with a small set of assumptions on preferences and shows that this set (i) naturally results in a taxonomy of distributional archetypes that nests all empirically relevant types considered in previous work; and (ii) gives rise to a clean experimental identification procedure – the Equality Equivalence Test – that discriminates between archetypes according to core features of preferences rather than properties of specific modeling variants. As a by-product the test yields a two-dimensional index of preference intensity.     

Scaling service delivery in a failed state: cocoa smallholders,Farmer Field Schools,persistent bureaucrats and institutional work in Côte d’Ivoire

The increased use of sustainability standards in the international trade in cocoa challenges companies to find effective modes of service delivery to large numbers of small-scale farmers. A case study of the Sustainable Tree Crops Program targeting the small-scale cocoa producers in Côte d’Ivoire supplying international commodity markets shifts attention from mechanisms of private governance to the embedding of service delivery in the institutional dynamics of the state. It demonstrates that, despite a recent history of violent conflict and civil unrest, the introduced Farmer Field Schools programme achieved a surprising scale in terms of numbers and geographical spread. The analysis of this outcome combines political science and anthropological studies of effective and developmental elements in the state with the interest in institutional work found in organization science. The scaling of a new form of service delivery is explained by the skilful practices of institutional work by managers of a public–private partnership. They have been professionally associated with the sector for a long time and had the capacity to embed new forms of service delivery in persistent pockets of bureaucratic effectiveness in a failed state.     

实施生产者责任延伸制度对中国自主品牌汽车企业的影响——基于挤出效应的实证研究

中国已经进入汽车社会，报废汽车回收利用产业不仅关系到资源利用、环境保护，而且关系到汽车产业的健康持续发展。本文基于挤出效应理论，实证分析了EPR 制度的实施对中国自主品牌汽车企业的影响。研究表明：① EPR 制度的实施对中国自主品牌汽车企业具有挤出效应，同时，合资品牌汽车企业推进EPR 制度的活动具有技术溢出效应，这一外部效应可以缓解EPR 的实施对自主品牌汽车企业的挤出程度；②基于受益者负担原理、责任原理和竞争原理，文章提出了实施生产者责任延伸制度的相关政策建议。     

Blaming suicide on NASA and divorce on margarine: the hazard of using cointegration to derive inference on spurious correlation

Contrary to common belief, cointegration testing may not distinguish between spurious relations and genuine ones. It is demonstrated that highly correlated series appear as cointegrated, even though common sense tells us that the underlying relation does not make sense. Empirical testing using simulated data, data from daily life and historical data on interest rates shows that cointegration may fail not only to detect spurious correlation but also to capture cointegration in a genuine relation. Cointegration testing to reveal spurious correlation can only be used in conjunction with theory, common sense and intuition.