地形因素与地质灾害分布相关性分析

基于河北省1∶5万地质灾害调查成果,选取具有代表性的崩塌、滑坡、泥石流地质灾害隐患3570处,采用图表统计分析法,对分布高程、坡度、汇水面积等地形因素进行分析,研究地形地势因素对河北省地质灾害的空间分布的影响,从而为各级行政主管部门对地质灾害的规划、预防提供参考。受制于人类居住环境等因素,河北省地质灾害在海拔高程、坡度、沟床比降等方面并非理论上的正相关性,而是呈抛物线型分布,其主要分布于海拔200~700 m的中低山区,崩塌发育坡度多大于60°,滑坡发育坡度多在20°~50°,泥石流汇水面积大多小于5 km 2,沟谷形态以V型谷为主,在山坡坡度大于25°,高差100~500 m,沟床比降213~105‰的区域集中分布。     

土地产权稳定能促进农户绿色生产行为吗？——以广东省确权颁证与农户采纳测土配方施肥技术为例证

土地产权趋于稳定将强化农户的剩余控制权和剩余索取权，进而激励农户改进农业生产行为，但这种激励具有情景依赖性：由于农户进行农业生产经营的能力和目的不同，并不是所有的农户都会因此而改进农业生产行为。采用2018年广东省“千村调研”数据，分析确权颁证对农户采纳测土配方施肥技术的影响，结果表明：农地确权颁证虽然赋予农户实现农地价值的剩余权，但能否促进农户采纳测土配方施肥技术还取决于农户自身的获益能力和收益本身的效用。如果农户缺乏实现农业生产超额利润的能力（低收入农户），即使土地产权趋向稳定，也难以产生采纳测土配方施肥技术的动力；如果实现农地价值的最优方式是“他用”而非“自用”，即使采纳测土配方施肥技术会带来农业生产超额利润，农户也不会积极采纳；如果农户具有实现农业超额利润的能力（高收入农户）和预期（以农业为主业的农户），则确权颁证会促进其采纳测土配方施肥技术。农地确权颁证对农户绿色生产行为的促进有着情景依赖性，因而，在农地确权颁证的同时要完善农地流转制度，通过土地产权稳定和流转稳定的双重激励更有效地促进农业生产经营主体积极施行绿色生产行为。     

The impact of non-performing loans on bank lending in Europe: An empirical analysis

In the aftermath of the global financial crisis, considerable attention has been paid to the accumulation of non-performing loans in the balance sheet of European banks and to its potential negative effects on bank lending to the real economy. Using a dataset composed of bank-specific information and country aggregates, we study the impact of the stock and the flow of non-performing loans on the lending activities of a sample of 75 European banks between 2014 and 2018. In general, higher rates of non-performing loans, together with other variables, are associated with lower growth rates of performing loans. This effect persists across several econometric specifications and is more significant for those banks exhibiting lower growth rates of performing loans. Similarly, our econometric analysis suggests that banks with higher decreases in their rate of non-performing loans tend to lend more to the real economy, an effect which is particularly intense at the right tail of the distribution. The findings of our paper can be useful for policymakers when addressing the resolution of non-performing loans in banks.     

How does corporate social responsibility affect financial performance,financial stability,and financial inclusion in the banking sector? Evidence from Pakistan

This paper examines the impact of corporate social responsibility (CSR) on the financial performance, financial inclusion, and financial stability of the banking sector, focusing on annual data for 20 Pakistani commercial banks for the period 2008–2017. The results suggest that CSR, as well as age and size, has a positive impact on all three factors. However, high levels of leverage reduce financial inclusion and financial stability, while financial inclusion is also negatively associated with the tangibility of assets.     

Transitions between equilibria in bilingual games under logit choice

We study the effect of introducing a bilingual option on the long run equilibrium outcome in a class of two-strategy coordination games with distinct payoff and risk dominant equilibria under the logit choice rule. Existing results show that in the class of two-strategy games under consideration, the inefficient risk dominant equilibrium is selected in the long run under noisy best response models. We show that if the cost of the bilingual option is sufficiently low then the efficient payoff dominant equilibrium will be selected in the long run under the logit choice rule.     

The Level and Stability of Institutional Ownership and Firm Performance: Evidence from Taiwan

The purpose of this paper is to investigate the influence of shareholding stability of institutional investors on firm performance. We analyze 647 sample companies listed in the Taiwan Stock Exchange from 2005 to 2009 using the coefficient of variance of institutional holding proportion as the measure for ownership stability. The empirical results show that increasing stability of institutional holdings is related to better firm performance. The low-risk and younger firms with higher CEO incentive compensation, larger insider holdings, and higher growth usually have better performance. Furthermore, when the long-term institutional shareholdings, particularly of foreign institutions, are higher, the firm performance is better.     

2种不同来源的黑牛肝菌SOD酶活稳定性研究

本研究分别对野生种PH-16与栽培种PH-20黑牛肝菌进行SOD酶活稳定性研究,通过SOD酶对H2O2及乙醇-氯仿的化学敏感性差异,确定SOD酶类型,以没食子酸自氧化法测定酶活,通过温度、pH以及4℃保藏时间梯度对其SOD酶稳定性进行了探究.结果表明,硫酸铵-丙酮复合沉降法,SOD酶活性最高,PH-20菌丝体蛋白含量是PH-16的1.32倍,而PH-16 SOD比活力最高可达PH-20的1.42倍.两种黑牛肝菌SOD酶活性均对H2O2浓度变化敏感,对乙醇-氯仿浓度变化保持活性稳定,确定SOD酶类型为Cu,Zn-SOD酶.PH-16 SOD酶最高酶活条件为pH=5.5,温度25℃,活性平均衰退速率16.2 U·mL-1·d-1.PH-20 SOD酶最高酶活条件为pH=6.5,温度30℃,活性平均衰退速率8.5 U·mL-1·d-1.     

非线性延迟系统Runge-Kutta方法的稳定性探讨

针对时间依赖型的非线性多变延迟系统,采用变步长的Runge-Kutta方法求解,证明了匹配一定插值方法的代数稳定的Runge-Kutta方法是VR稳定的。     

人民币汇率制度改革:影响与稳定性

近年来,人民币汇率问题一直是各方面争论的焦点。现在,人民币汇率升值2%,并且不再盯住单一美元,而是参考“一篮子货币”定值。由于人民币汇率调整幅度比较小,所以,短期内会对我国经济产生一定的影响,从长期来看,影响比较小。人民币汇率水平,短期内是会保持比较稳定,但长期来看又存在着值得注意的问题。     

一种改进型声表面波滤波器在接收机中的应用

针对应用于接收机中中心频率为898.144MHz的声表面波滤波器的缺点,提出了一种改进型的滤波器.改进型的声表面波滤波器采用镜像阻抗连接低插损结构,大大改善了幅频特性,提高了选择性和温度稳定性.将其应用到接收机中,经试验验证效果良好.