华北地区某污水处理厂升级改造工程实例

华北地区某城市污水处理厂升级改造工程处理规模为50万t/d,原设计为A/O脱氮工艺,执行《城镇污水处理厂污染物排放标准》(GB 18918-2002)二级排放标准。由于近年来进水水质严重恶化以及对污水排放标准的提高,需对原污水处理系统进行改造,通过技术方案对比,在原生物处理段增加厌氧池,使之变为A2/O脱氮除磷,新增深度处理工艺为反硝化生物滤池-加砂沉淀池-滤布滤池-紫外消毒,使出水水质达到一级A排放标准。     

Female participation in African labor markets: The role of information and communication technologies

This article investigates the effects of information and communication technologies (ICT) on female labor force participation in a sample of 48 African countries. We specify and estimate linear regression and dynamic panel data models with fixed effects (FE) and system-generalized method of moments (SYS-GMM) estimation over the period 2001–2017. The three main results are that ICT use (mobile phone and internet) significantly stimulates female labor force participation in Africa; this effect is enhanced by financial development and female education; the effect of ICT on female employment in Africa is strongest in the industrial sector. These results remain robust to the provision of social, cultural, and institutional variables.     

Can mobile phones improve gender equality and nutrition? Panel data evidence from farm households in Uganda

Since 2000, mobile phone technologies have been widely adopted in many developing countries. Existing research shows that use of mobile phones has improved smallholder farmers’ market access and income. Beyond income, mobile phones can possibly affect other dimensions of social welfare, such as gender equality and nutrition. Such broader social welfare effects have hardly been analyzed up till now. Here, we address this research gap, using panel data from smallholder farm households in Uganda. Regression results show that mobile phone use is positively associated with household income, women empowerment, food security, and dietary quality. These results also hold after controlling for possible confounding factors. In addition to the household-level analysis, we also look at who within the household actually uses mobile phones. Gender-disaggregation suggests that female mobile phone use has stronger positive associations with social welfare than if males alone use mobile phones. We cautiously conclude that equal access to mobile phones cannot only foster economic development, but can also contribute to gender equality, food security, and broader social development. Further research is required to corroborate the findings and analyze the underlying causal mechanisms.     

New perspectives on farm size and productivity

The farm size and productivity debate has been limited by the focus on land or labor productivity, generally showing respective productivity advantages to smaller or larger sized farms. Our purpose is to provide new perspectives on the debate by bringing together evidence from a set of novel case studies in both rich and poor countries. Common to them are the adoption of total factor productivity (TFP) as the comparative performance measure, and the reliance on panels of farm micro data. The present article presents a synthesis of findings from five case studies in (i) Malawi, Tanzania, and Uganda; (ii) Bangladesh; (iii) Brazil; (iv) Australia; and (v) the United States. The preponderance of evidence from these studies suggests that there is no single economically optimal agrarian structure; rather, it appears to evolve with the stage of economic development. Certain farm sizes face relative productivity advantages, such as small farms in Africa. But with economic and market growth, that smallholder advantage will likely attenuate, moving toward constant and eventually increasing returns to size. Yet, importantly, small farms may be quite dynamic, and need not be a drag on agricultural growth until perhaps well into the development process.     

Are China’s regional agricultural productivities converging: How and why?

This article tests the hypotheses of convergence to a single level of total factor productivity (TFP), and a steady state of TFP growth rate in China’s agricultural sector. Based on multilateral TFP estimates we found that China’s agricultural sector has rebounded in recent years from a slower TFP growth in the 2005–2007 period. While convergence test results confirm a “catch-up” effect that provinces with lower TFP levels tend to grow faster than others, estimated rates of β convergence are conditional on how we capture the heterogeneity effect across regions. The rates of β convergence range from 0.016 to 0.039 under different model specifications. Estimates show that higher growth rates of educational attainment, R&D, and intermediate goods density (per unit of labor) can enhance TFP growth. Unfortunately, there is no evidence of an overall σ convergence, indicating that TFP levels are not converging except in the South region. It implies that to catch up with leading provinces, it would require extra efforts for those lagging behind by increasing their region-specific research investment, promoting rural educational attainment, and enhancing embodied technical change.     

Club convergence and drivers of digitalization across Indian states

Disparity in the level of digitalization is a crucial driver of economic inequality in an economy. Although a pocket of its population is still bereft of the benefits of digitalization, India currently has the second highest number of internet subscribers in the world despite the nation's late adoption of digital technology. An accurate assessment of the current state of digitalization in the country is required for devising effective initiatives towards building a Digital India and bridging the nation's internal digital divide. Considering 17 major Indian states and 21 variables for 10 years, we constructed a composite index of digitalization with the help of Principal Component Method (PCM). This paper identifies factors responsible for the digitalization divide across states. In the second part of the analysis, the study confirms, with the help of club convergence test, the absence of overall convergence towards digitalization and the existence of the non-convergent group. This paper also shows that the non-convergent group of states are at the bottom of the ranking table which indicates the need for greater attention to initiatives to bridge the digital divide.     

Does computer penetration increase farmers’ income? An empirical study from China

The diffusion and adoption of modern information technology provide new chance for China to close urban-rural income gap. This paper uses China's provincial panel data from 2002 to 2013 to investigate the effect of computer penetration on rural residents' income. A public program aiming to connect every village with broadband Internet and other rural facilities provides plausibly exogenous variation in rural residents' availability and adoption of the broadband Internet, which is used to explore the instrument variable for rural computer penetration. The results show that rural computer penetration tends to increase rural residents' income over time, but the average effect remains limited. The dynamic panel threshold effects model, which allows for both the threshold variable and other covariates to be endogenous, is further used to explore the constraints of the income-increase effect of rural computer penetration. It shows that the effect is at least doubled over the average effect estimated from instrument variables method, once the digital divide causes are removed. Our findings have important implications for the government to increase rural residents' income and reduce urban-rural income gap by encouraging rural computer usage and removing the digital divide.     

Impact of modern communication infrastructure on productivity,production structure and factor demands of US industries: Impact revisited

This study investigates the contribution of modern communication infrastructure characterized by high speed broadband access network on the productivity growth, production structure and factor demands for US industries and for the aggregate economy. To evaluate such contribution, we modify the traditional cost function by incorporating communication infrastructure as input in production process in conjunction with other public infrastructures. The network externality and spillover effect of broadband access technology are captured by introducing broadband penetration rate as a shift factor in industry level production function. Empirical results show that the increased use of modern communications infrastructure increases the productivity of all industries with wide variations across industries. Estimated impacts on input demands show that increase in use of communications infrastructure service saves labor and materials and increase the demand for private capital. Finally, aggregate social rate of return on such investment has been estimated for policy implications.     

Masculinity,Testosterone, and Financial Misreporting

We examine the relation between a measure of male CEOs’ facial masculinity and financial misreporting. Facial masculinity is associated with a complex of masculine behaviors (including aggression, egocentrism, riskseeking, and maintenance of social status) in males. One possible mechanism for this relation is that the hormone testosterone influences both behavior and the development of the face shape. We document a positive association between CEO facial masculinity and various misreporting proxies in a broad sample of S&P1500 firms during 1996–2010. We complement this evidence by documenting that a CEO's facial masculinity predicts his firm's likelihood of being subject to an SEC enforcement action. We also show that an executive's facial masculinity is associated with the likelihood of the SEC naming him as a perpetrator. We find that facial masculinity is not a measure of overconfidence. Finally, we demonstrate that facial masculinity also predicts the incidence of insider trading and option backdating.     

Effects of hiring former employees of multinationals in the absorptive capacity of local firms

The attraction of foreign direct investment seeks, among other things, to increase the productivity of local companies through knowledge spillovers. However, the empirical evidence in this regard is contradictory. One influential factor is the absorptive capacity of the local companies. This article analyzes the effect of the presence of former employees of multinational corporations as employees of local companies, on the absorptive capacity of said companies. The study was done in Costa Rica, a country known for its successful strategy in the subject matter. The data come from a survey applied to 1167 companies by the Observatorio Costarricense de las Pymes in 2011. It was found that the hiring of former employees of multinational corporations by local companies has a positive effect on the index of absorptive capacity of companies in all productive sectors. Specifically, this hiring of former employees increases the index of absorptive capacity by nine percentage points, with differences by sector and the size of the company.