Peng Gui’s research while affiliated with Institute of Scientific and Technical Information of China and other places

Millimeter waves (mmWave) are the only viable solution that is practical to fulfil the enormous bandwidth requirement of the modern era communication systems. Accurate estimation of the wireless channels is necessary for mmWave based multiple input multiple output (MIMO) systems that use directional beamforming. Nevertheless, due to the short wavelengths, mmWave channels exhibit significant variability, which poses a major obstacle to their successful recovery within limited training durations traditionally, there are two conventional channel estimation methods have been used for the operation. One is by using the low rank property of channel matrix and the other is to exploit the sparsity of the channel matrix in angle domain. However, the conventional estimation approaches may have necessitated a high-dimensional channel matrix, so substantially augmenting the intricacy of the traditional channel estimation process. This study addresses the channel estimation problem of wideband mmWave MIMO system by utilizing both low rank and sparsity simultaneously. The fundamental concept of the proposed technique is to frame the channel estimation issue as a combined optimization problem that creates an objective function comprising of l1-norm${{\boldsymbol{l}}}_{1}-{\boldsymbol{n}}{\boldsymbol{o}}{\boldsymbol{r}}{\boldsymbol{m}}$ and nuclear norm minimization problems. The joint optimization problem is tackled using the expanded version of alternating direction method of multipliers (ADMM) algorithm which takes the advantage of the low rank and sparseness of the channel matrix by using the relaxation technique of the variables. The simulation findings clearly illustrate the superiority of proposed approach in comparison to other benchmarks.

The agricultural sector is a crucial driver for sustainable development in many countries , as it directly or indirectly contributes to various United Nations Sustainable Development Goals. However, this sector requires increasing financial investment to rejuvenate and modernise production processes. This study investigates the impact of private sector investment on agricultural production across selected Asian countries from 2001Q1 to 2020Q4. The results of the Driscoll-Kraay regression and the method of moments quantile regression reveal that private agricultural investment positively affects agricultural production. The findings indicate positive contributions from agricultural aid, domestic credit, and rural population, whereas remittances negatively affect agricultural production. The Dumitrescu-Hurlin panel causality test results establish bidirectional causality between farm production and its determinants (private agricultural investment, agricultural aid, domestic credit, remittances, and the rural population). Based on these findings, we recommend that policymakers and governments incentivise and facilitate private agricultural investment to drive sustainable development. This strategy could boost agricultural productivity and enhance a more resilient agricultural system capable of withstanding environmental challenges while improving farmers' incomes and livelihoods.

This study advances the United Nations Sustainable Development Goals, specifically focusing on Goal 3 (Good Health and Well-Being) and Goal 13 (Climate Action). This study uses novel analytical techniques that consider cross-sectional dependencies, intra-cluster correlation, endogeneity, and parameter heterogeneity to explore the relationship between climate change and human well-being in Asian countries from 1990Q1 to 2019Q4. Our empirical results show three things. First, an inverse relationship exists between temperature and human well-being in Asian countries. Second , we observe a robust positive impact of rainfall on human well-being in Asian countries. Lastly, there is a one-way causal effect from rainfall to human well-being and a two-way causal relationship between temperature and human well-being. Our robust results, therefore, suggest that developing comprehensive economic plans to promote public welfare can create a positive feedback loop where enhanced well-being drives greater economic engagement and prosperity.

Climate change is a confounding factor that affects food security in several ways. Although the analyses of earlier studies in this area were largely non-technical, new analytical techniques have been developed to comprehensively evaluate climate change patterns and their implications for food security. In this study, we use recent developments in panel econometrics, which consider cross-sectional dependence and parameter heterogeneity, to examine the effects of climatic conditions on cereal farming in Africa from 1970Q1 to 2017Q4. The results show that rainfall positively affects cereal crops, although average temperatures are typically unfavourable. In the country-specific scenarios, we observed significant variations in the influence of climatic conditions on cereal production. The causality test results show a two-way causal relationship between climatic conditions—rainfall and temperature—and cereal production. It is suggested that African governments and non-governmental organisations support farmers' adaptation to climate change by implementing policies that prioritise farmers' capacity building and ensure that extension service officers engage with farmers intensively.

The Nigerian government is committed to sustaining rice production to meet national demand. Nevertheless, political tension and climate-induced stressors remain crucial constraints in achieving policy targets. This study examines whether climate change and political instability significantly threaten rice production in Nigeria. First, we employed nonparametric methods to estimate the country's rainfall and temperature trends between 1980Q1 and 2015Q4. Second, we employed the autoregressive distributed lag (ARDL) technique to examine the effects of climate change and political instability on rice production. The results show that while temperature has an increasing pattern, rainfall exhibits no significant trend. The findings from the ARDL estimate reveal that rice production responds negatively to temperature changes but is less sensitive to changes in rainfall. In addition, political instability adversely affects rice production in Nigeria. We argue that Nigeria's slow growth in rice production can be traced back to the impact of climate change and political tension in rice farming areas. As a result, reducing the overall degree of conflict to ensure political stability is critical to boosting the country's self-sufficiency in rice production. We also recommend that farmers be supported and trained to adopt improved rice varieties less prone to extreme climate events while supporting them with irrigation facilities to facilitate rice production.

The relationship between energy, environment, and economic growth has been received a lot of attention recently among scientific studies, but environmental sustainability remains a global issue. Renewable energy development, green technological innovations, and regulatory policy mechanisms can all help to reduce greenhouse gas emissions and support environmental sustainability. The purpose of this study was to look at the influence of renewable energy development, market regulation, and environment-related innovation on CO2 emissions in the BRICS countries from 1990 to 2020. For empirical analysis, it uses second-generation panel unit root test and updated linear and nonlinear cointegration techniques. To this end, this study employs symmetric and asymmetric approach to linear and nonlinear relationship among study variables. The findings indicate that there is long-run symmetric and asymmetric relationship between renewable energy development, market regulation, environment-related innovation, and CO2 emissions. The market regulation plays significant mediating role in relation between renewable energy development, environment-related innovation, and CO2 emissions. Our findings suggest that BRICS countries need to more focus on the environment-related innovation and renewable energy development. They should design market-based environmental regulation policies, emphasize on environmental taxes, expand renewable energy development, and environment-related innovations. Such strategies are key to limiting CO2 emissions and gain environmental sustainable.

The past few decades of extreme drought and flooding caused by changing climate conditions have significantly affected agricultural production globally. This study focuses on two vital crops in China—maize and rice—and provides a comprehensive analysis of how these crops are affected by climate change-induced factors over the periods 1978Q1–2015Q4. Four key findings were obtained. First, using a nonparametric approach to estimate actual and observed trends of climatic variables, the results show a significant positive trend in average temperature from February to October. On the other hand, seasonal temperature increases during spring, summer, and autumn. Second, the results show no significant change in the monthly, seasonal, and annual rainfall patterns when examined over the study period. Third, using an autoregressive distributed lag (ARDL) model, we find that while temperature and rainfall do not significantly support rice production in the long and short run, they play a substantial role in maize production in China. Finally, we find no significant difference in the results for rice when the quantile regression (QR) technique that controls for distributional asymmetry effects is employed. However, the impact of temperature on maize decreases at higher quantiles. Given the outcomes of our study, we argue that an advanced irrigation system is crucial and must be encouraged to minimize the effects of climate change on crop production.

The relationship between energy, environment, and economic growth has been received a lot of attention recently among scientific studies, but environmental sustainability remains a global issue. Renewable energy production, technological advancement, and regulatory policy mechanisms can all help to reduce greenhouse gas emissions and support environmental sustainability. The purpose of this study was to look at the influence of renewable energy development, market regulation, and technological innovation on carbon emissions in the BRICS countries. Renewable energy development is measured by the contribution of renewables to the total primary energy supply. The market regulation represents the measure of environmental regulation policies that the state administrative department uses to manage or limit pollution. Technological innovation is measured by environment-related technologies. To examine the symmetric and asymmetric relationship between study variables, we used a second-generation panel unit root test, linear and nonlinear co-integration tests, and linear and nonlinear ARDL. Using a symmetric approach, we found that renewable energy development, technological innovation, and market-based environmental regulation policies had a considerable positive impact on lowering carbon emissions (CE). Furthermore, the combined effect of market regulation and renewable energy development, as well as market regulation and technology innovation on CE is negative and significant. In the asymmetric specification, we found that positive and negative shocks are not uniform but vary according to ascending and descending movement in the primary variables. In nonlinear specification, the long run effects are higher than the short run. The study suggests renewable energy development, technical innovation, and market-based regulation environmental policies are the main mechanisms to reduce carbon emission in BRICS countries.