基于自由摆的平板控制系统研究

系统以STC89C51单片机、ADXL345芯片和步进电机为核心部件.由按键控制实现不同过程的切换,通过角度传感器对摆杆的位移、运动方向进行检测,并将数据反馈给单片机.结合独特的数学及物理公式的算法实现了平板动态平衡和定点指向功能,并通过高分辨率的LCD对倾角进行显示.     

Lifecycle effects on consumer financial product portfolios in South Africa: An exploratory analysis of four ethnic groups

This paper assesses ownership of 16 financial products by households in different lifecycle stages amongst four ethnic groups (Africans, Coloureds, Asians, and Whites) in South Africa. The lifecycle hypothesis indicates younger households should own more debt-related financial products, whereas households in intermediate lifecycle stages should own more financial products to accumulate assets; both these claims are disconfirmed for all groups. However, White households in intermediate household stages own more financial products than younger and older households, consistent with previously reported lifecycle findings in Western countries. Consistent with the literature on innovation adoption we find that younger, affluent and highly educated households amongst the other three ethnic groups tend to own more financial products than older Africans, Coloureds and Asians. These results indicate that innovation adoption literature may better describe financial product ownership in developing countries than the lifecycle hypothesis.     

基于单片机控制的电子密码锁

随着人们生活水平的提高,如何实现家庭防盗这一问题也变得尤为突出,传统的机械锁,由于其构造的简单,安全性能低,无法满足人们的需要.随着电子产品的不断发展,单片机已成为电子产品研制和开发中首选的控制器.为了更好地推广单片机在家电领域中的应用,介绍了一种应用AT 89C2051单片机设计的电子密码锁.经实验验证该密码锁具有安全、实用、成本低等特点,符合住宅用锁的要求,可作为产品进行开发.     

Dictator game variants with probabilistic (and cost-saving) payoffs: A systematic test

Driven by methodological concerns, theoretical considerations, and previous evidence, I systematically test the validity of common dictator game variants with probabilistic payoffs. Using a unified experimental framework, I include four approaches and compare them to a standard dictator game: involving fewer receivers than dictators, paying only some players, paying only some decisions, and role uncertainty. I also relate transfers in the dictator game variants to established complementary individual difference measures of prosociality: social value orientation, personal values, a donation to charity, and the Big Five personality factor agreeableness. My data shows that the standard dictator game presents the expected correlations with the complementary measures of prosociality. Involving fewer receivers yields comparably valid results. By contrast, when only some players or decisions are paid or, particularly, when subjects face role uncertainty, the expected associations with complementary prosociality measures are distorted. Under role uncertainty, generosity is also significantly biased upward. I conclude that the validity of dictator game outcomes is highly sensitive to the applied methods. Not all dictator game variants can be recommended for the valid measurement of social preferences.     

An alternative assessment of global climate policies

This paper analyzes alternative pricing schemes for funding investment in climate policies. This paper proposes a new policy scenario, explicitly disentangling the issue of burden sharing of financing new investments from the issue of taxation energy consumption and therefor emissions. We compare traditional allocation schemes with an optimal Ramsey pricing by applying demand elasticity values, derived from empirical estimations of household behavior for the 106 leading countries in the world, representing around 90% of total world energy consumption and carbon emissions in 2014. We calculate country-specific alternative taxation options: uniform, equitable and Ramsey pricing schemes, applied to households, assessing the related welfare effects. Our results show that the optimal pricing scheme, for a given investment need, can improve world welfare at the expenses of equitable considerations. In addition, the aggregate societal benefit outweighs the losses associated with specific group of countries, paving the way for easier political agreement, using compensation schemes to redistribute the proceeds.     

Does export concentration matter in economic adjustment programs? Evidence from the euro-area

The recent crisis in some euro area countries is intensively fueling the political and economic policy debate about the effectiveness of the applied adjustment programs. This paper aims to contribute to explaining why the results of these programs could be different across countries, flagging the crucial role of exports. In view of recent economic literature about substitution between domestic and foreign sales, helping exports when domestic demand is adjusting, this paper uses panel data techniques to assess the role of the export structure in explaining this substitution effect in the euro area countries. Building a novel indicator for product concentration, the results suggest that domestic demand developments are more relevant to explaining exports in countries with a lower product concentration index (that is, more diversified exports). This contributes to explain why euro area countries under stress registered different economic performance, in particular the clearly less favorable behavior of Greece, where exports structure is concentrated more strongly in some goods and services than in other euro area countries. With different export behavior the final evaluation of the Greek adjustment would be certainly different. These results suggest that export structure should be taken into consideration when designing or evaluating this type of adjustment programs.     

A method for high-dimensional smoothing

We consider the problem of the computation of smoothed additive functionals, which are some integrals with respect to the joint smoothing distribution. It is a key issue in inference for general state-space models as these quantities appear naturally for maximum likelihood parameter inference. The computation of smoothed additive functionals is very challenging as exact computations are not possible for non-linear non-Gaussian state-space models. It becomes even more difficult when the hidden state lies in a high dimensional space because traditional numerical methods suffer from the curse of dimensionality. We propose a new algorithm to efficiently calculate the smoothed additive functionals in an online manner for a specific family of high-dimensional state-space models in discrete time, which is named the Space–Time Forward Smoothing (STFS) algorithm. The cost of this algorithm is at least $O\left(N^2{d}^{2}T\right)$, which is polynomial in $d$. $T$ and $N$ denote the number of time steps and the number of particles respectively, while $d$ is the dimension of the hidden state space. Its superior performance over other existing methods is illustrated by various simulation studies. Moreover, STFS algorithm is successfully applied to perform Maximum Likelihood estimation for static model parameters both in an online and an offline manner.     

The Introduction of Matrix Algebra into Statistics

Primary credit for the introduction of matrix algebra into statistics is given to A. C. Aitken in the 1930s.     

Trade and poverty nexus: A case study of Sri Lanka

The link between trade liberalisation and poverty has become one of the most debated topics in recent years. There is a growing body of empirical literature on this topic and many studies provide mixed results. In this study, Sri Lanka is used as a detailed case study and a computable general equilibrium (CGE) approach is used as an analytical framework to examine the trade-poverty nexus. The results suggest that, liberalisation of the manufacturing industries is more pro-poor than that of the agricultural industries. Overall, this study suggests that trade reforms may widen the income gap between the rich and the poor creating uneven gains across different household groups in Sri Lanka. While short-term complementary policies are needed to compensate vulnerable income groups, long-term policies are needed to make gains from trade liberalisation more inclusive and equitable to maintain economic and political stability in Sri Lanka.     

Towards a more integrated, symmetric and viable EMU

The capacity of the EMU system to successfully tackle an economic crisis has been questioned during the recent financial and economic turmoil. The basic economic structure and competitiveness in the eurozone has developed in an undesirable direction. The number of member countries of the EMU, as well as the basic construction of the EMU system, must again be the focus of the discussion. After a study of the current accounts of 12 EMU countries follows a discussion in terms of the Barro–Gordon model about the costs of the EMU, i.e., to bring together the preferences of the political authorities in different EMU countries and the optimal combination of inflation and employment in the eurozone to determine the sought equilibrium of the model. If economic structural differences are increasing, they must be compensated by increased integration. It is feasible, but only for the economically viable EMU countries.