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1.
调查2011—2012年军队评价性药品监督抽验情况。方法:对1211批检品的抽验情况及其质量情况进行统计与分析。结果:医院自制制剂质量问题较为严重,且主要分布在液体制剂和原辅料营养物质丰富以及以中药材直接入药的制剂。结论:药品监管部门应加强监管并提高技术监督的能力,相关企业应增强社会责任感。  相似文献   
2.
This paper concerns redistribution via nonlinear income taxation in an overlapping generations model with two ability-types. We assume that the wage rates are determined by bargaining between unions and firms, meaning that the equilibrium is characterized by involuntary unemployment. We show that the policy instruments that are used to calculate the marginal labor income tax rate for each ability-type give rise to intertemporal tax base effects. In addition, since the relationship between the employment and the capital stock implies intertemporal production inefficiency at the second best optimum, imperfect competition in the labor market may itself justify capital income taxation.   相似文献   
3.
基于交易成本的消费者网络购物意愿的实证研究   总被引:2,自引:0,他引:2  
首先对网络购物中的交易成本相关研究进行文献综述,在此基础上,建立网络购物中消费者交易成本影响因素的相关研究假设,运用PLS—SEM模型的研究方法,采用问卷调研获取的数据,对消费者网络购物意愿进行了实证分析。研究表明,购买频率和不确定性显著地影响交易成本,不确定的影响作用较大,并最终对购买意愿产生影响。  相似文献   
4.
    
The COVID-19 recession that started in March 2020 led to an unprecedented decline in economic activity across the globe. To fight this recession, policy makers in central banks engaged in expansionary monetary policy. This paper asks whether the measures adopted by the US Federal Reserve (Fed) have been effective in boosting real activity and calming financial markets. To measure these effects at high frequencies, we propose a novel mixed frequency vector autoregressive (MF-VAR) model. This model allows us to combine weekly and monthly information within a unified framework. Our model combines a set of macroeconomic aggregates such as industrial production, unemployment rates, and inflation with high-frequency information from financial markets such as stock prices, interest rate spreads, and weekly information on the Fed's balance sheet size. The latter set of high-frequency time series is used to dynamically interpolate the monthly time series to obtain weekly macroeconomic measures. We use this setup to simulate counterfactuals in absence of monetary stimulus. The results show that the monetary expansion caused higher output growth and stock market returns, more favorable long-term financing conditions and a depreciation of the US dollar compared with a no-policy benchmark scenario.  相似文献   
5.
Resource economists are often asked to value a proposed change at one, and only one, recreational site; the model we develop and estimate is applicable for those cases. The application is valuing the elimination of fish consumption advisories on a large bay on Lake Michigan. The model is minimal but complete: complete in that the choice set is not restricted, minimal in that only two conditional indirect utility functions are estimated. It is utility-theoretic and one does not have to collect characteristic data on all of the other fishing sites in the region. Data include the number of trips each individual currently takes to Green Bay, answers to "would you prefer to fish Green Bay under conditions A or B?" and how often each angler says they would fish Green Bay under different sets of conditions.  相似文献   
6.
Measures of potential output and the output gap are increasingly being developed and used to concisely quantify and monitor the risk of price accelerations stemming from rises in aggregate demand that are not met by a corresponding increase in supply. They often play a prominent role in the price determination mechanisms of macroeconometric models. In this paper we build a measure of potential private-sector value added for the Italian economy that is consistent with the capital accumulation process in the Banca d'Italia's Quarterly Model — and more generally with the rest of the supply-side block of that model. More specifically, we exploit the fact that the investment function can be thought of as a relationship transforming desired gross additions to capacity output into capital accumulation by means of a conversion factor (the optimal capital/output ratio). Thus, if one removes the component of investment decisions that stems from changes in the relative price of the production factors, (i.e. in the optimal capital/output ratio), then a measure of the desired gross addition to capacity may be constructed. The results draw a cyclical picture of the degree of capacity utilisation for the period 1970–1997 that is roughly in line with those produced by the Wharton and Hodrick–Prescott filter approaches, as well as with the pictures resulting from the ISAE, IMF, European Commission and OECD measures of the output gap. Our investment-function-based measure appears to be a promising indicator of the pressure exerted on prices by demand accelerations. Its empirical properties are, on the whole, acceptable and plausible.  相似文献   
7.
高频地波雷达(HFGWR)受到严重的射频干扰影响。单频射频干扰在接收信号中体现为高强度的线性调频信号,从而污染所有距离元。为抑制射频干扰,通过分析其频率特征,使用分数阶傅里叶变换(FRFT)将原始信号转换到分数阶傅里叶域,对射频干扰对应的谱峰置零,达到抑制干扰的目的。该方法的优点在于抑制射频干扰的同时无损干扰位置处的回波信号,无需重构信号。实测数据分析表明:FRFT不仅能有效抑制射频干扰,信噪比提高可达10 dB以上,而且其计算复杂度较小,满足雷达实时工作要求。  相似文献   
8.
以华东地区为例,对4A级景区(点)和旅游线路中的对应关系进行了研究,揭示了部分4A级景区(点)在旅游线路中出线频率较低的现象和深层次原因,指出了现有旅游线路产品过于单调而又缺乏新意,其产品设计以及市场开发尚有巨大的发展潜力。4A级旅游景区(点)可以更多地利用旅游线路而增加销售渠道;旅游线路产品的设计应该更趋多样化,充分发挥4A级景区(点)对旅游线路的支撑作用,全面提高4A级景区(点)利用率,以满足不同层次消费者的需求。  相似文献   
9.
陆前进 《金融研究》2016,431(5):35-50
本文从宏观经济的一般均衡模型出发,融入了股票价格和房地产价格变动,考察我国中央银行货币政策调控在经济增长和通货膨胀之间的目标规则,分析了影响货币政策规则参数变化的主要因素及潜在机制。本文的实证结果显示中央银行最优货币政策参数为0.144055,央行货币政策是逆周期操作,也意味着中央银行在制定货币政策时,赋予通货膨胀目标更高的权重;同时我国货币政策是逆房地产市场周期、顺股市周期的。进一步,本文从最优货币政策的角度考察了我国货币状况指数的权重。根据最优货币政策规则,货币状况指数权重为0.302876,即利率上升1%相当于汇率下降0.30%,意味着利率变动的效果要小于汇率变动的影响。  相似文献   
10.
近年来,随着极端暴雨事件的出现,导致城市内涝灾害频繁发生,原有降雨历时仅为2h的市政排水设计暴雨强度公式已无法满足城市暴雨设计的需求,因此就要延长暴雨采样历时,推求出长历时(24h)暴雨强度公式。针对以上问题,根据北京市提供的52a(1961-2012)原始降雨资料并进行数字化处理,结合水利的长历时特点,采用兼顾市政排水,水利排涝,内涝防治的采样方法,应用P-Ⅲ分布曲线进行频率分析后采用6种经典方法推求暴雨强度公式的参数值,优选出误差最小且满足规范要求的暴雨强度公式参数值,进而推求长历时暴雨强度公式,在此基础上与短历时暴雨强度公式比较,分析两者的差异,为城市雨水排除规划设计提供科学依据和参考。  相似文献   
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