VGTU Journals (Vilnius Gediminas Technical University - Vilnius Tech)
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Sustainable urbanization and green total factor productivity: evidence from China’s new-type urbanization plan
No full textSustainable urbanization is significant in developing countries. This paper studies whether Chinese-type sustainable urbanization, that is new-type urbanization, promotes green total factor productivity (GTFP). We find that the new-type urbanization implementation in China, on average, significantly promotes GTFP by 3.2%. The positive effect of new-type urbanization on GTFP is correlated with promoting innovation, especially green innovation, and improving allocation efficiency. We do not find clear evidence for industrial upgrading, including industrial advancement and rationalization. This is because industrial upgrading is a gradual process and cannot be achieved shortly. Instead, we find that pilot cities might screen the entry of new firms and keep polluting firms out comparatively. The heterogeneous results indicate that the promotion effects on GTFP are more salient in regions with strong environmental regulation and adequate factor endowments. We have some practical implications for sustainable development in developing countries.
First published online 17 September 202
Discrete group method for a mathematical model of the diffusion in swelling gelatin
No full textIn this article, we will introduce the mathematical model of the diffusion process in a swelling medium that has already been modeled. The main purpose of this paper is introducing a new class of group transformations for solving the nonlinear emulsion equation. Thus, we introduce this method as the discrete group methods based on solvable class orbits. One of the crucial advantages of this method is that a transformation is sought, which reduces the equation being investigated to some standard form for which the methods of integration are known. In developing this approach, one may construct all canonical forms of solvable equations
An effective numerical algorithm for coupled systems of Emden-Fowler equations via shifted airfoil functions of the first kind
No full textThe present paper deals with the designation of a new efficient numerical scheme for numerical solution of a class of coupled systems of Emden-Fowler equations describing several processes in applied sciences and technology. This method combines the shifted version of airfoil functions of the first kind (AFFK) and quasilinearization technique. More specifically, the quasilinearization technique is first applied to the original problem and the shifted AFFK (SAFFK) collocation matrix technique is then constructed for obtaining the solution of resulting family of submodels. We derive the error bound and analyze the convergence properties of the SAFFK. Computational and experimental simulations are carried out to describe the applicability and accuracy of the new technique. To show the benefit of the new approach, the computed numerical outcomes are compared with those results obtained via the Bernoulli and Haar wavelets collocation methods. It is evident from the numerical illustrations that the new developed scheme is superior to the existing available ones. The elapsed CPU time of the proposed method is provided
Assessment of groundwater quality for irrigation purpose using irrigation water quality index (IWQI)
No full textGroundwater represents an important natural resource for sustaining life. This study was conducted to evaluate groundwater in the Doukkala region in Morocco, using the Irrigation Water Quality Index (IWQI) and uses Inverse Distance Weighting (IDW) in GIS was to show the spatial distribution of water quality parameters. It collected 97 of samples from groundwater and were estimated the sodium concentration (Na%), and sodium absorption rate (SAR), Also, Residual sodium carbonate (RSC), Kelly index (KI), magnesium content (MR), salinity potential (PS), and permeability index (PI). According to the distribution map of the Irrigation Water Quality Index (IWQI) for the study area, about 22.7% of samples fall into the severe restriction (SR) category, which can be used to irrigate plants with high salinity tolerance, 34.02 of samples fall under the high restriction (HR) category, 23.7% of samples fall into the moderate restrictions (MR) category, 17.52% of samples fall under the low restriction (LR) category, and 2.06% of samples fall under the no restriction (NR) category. The results of (IWQI) indicated that the groundwater quality in the study area is mostly suitable for irrigation purposes
Evaluating the performance of machine learning approaches in predicting Albanian Shkumbini River\u27s waters using water quality index model
No full textA common technique for assessing the overall water quality state of surface water and groundwater systems globally is the water quality index (WQI) method. The aim of the research is to use four machine learning classifier algorithms: Gradient boosting, Naive Bayes, Random Forest, and K-Nearest Neighbour to determine which model was most effective at forecasting the various water quality index and classes of the Albanian Shkumbini River. The analysis was performed on the data collected during a 4-year period, in six monitoring points, for nine parameters.The predictive accuracy of the models, XGBoost, Random Forest, K-Nearest Neighbour, and Naive Bayes, was determined to be 98.61%, 94.44%, 91.22%, and 94.45%, respectively. Notably, the XGBoost algorithm demonstrated superior performance in terms of F1 score, sensitivity, and prediction accuracy, the lowest errors during both learning (RMSE = 2.1, MSE = 9.8, MAE = 1.13) and evaluating (RMSE = 0.0, MSE = 0.01, MAE = 0.01) stages. The findings highlighted that Biochemical oxygen demand (BOD), Bicarbonate (HCO3), and Total Phosphor had the most positive impact on the Shkumbini River’s water quality. Additionally, a statistically significant, strong positive correlation (r = 0.85) was identified between BOD and WQI, emphasizing its crucial role in influencing water quality in the Shkumbini River
Spatio-temporal evolution and driving factors of landscape pattern in minority villages: a case study of Zahan Village in Hainan Province
No full textEthnic minority settlements, as an important medium for the transmission of ethnic cultures, are also a key resource for accelerating the development of ethnic minorities and the regions where they are located. Currently, research on landscape patterns focuses on traditional villages and ancient villages, whereas there is a relative lack of discussion on ethnic minority settlements. This study focuses on the multi-ethnic Zahan Village in Hainan Province, adopting the analysis methods of landscape pattern index and land-use transfer matrix, based on the theoretical framework of landscape ecology, to systematically analyze the spatial and temporal characteristics of the landscape pattern of the village and its patterns between 2007 and 2022, and to qualitatively analyze the influencing factors of its landscape changes from two dimensions, namely, humanities and nature. Research findings: (1) As the dominant landscape type, the proportion of woodland (although decreasing year by year) still exceeds 80%, whereas other land types, such as watersheds and grasslands, are gradually transformed into construction land and arable land, whose increment is significant. (2) During the study period, Throughout the study period, the landscape homogeneity of Zahan Village became better and better, the landscape types tended to be richer, and the spatial heterogeneity of the landscape also increased. (3) The area of woodland landscapes shows a decreasing trend from year to year, whereas construction land and arable land show an overall increasing trend, and the area of watersheds and meadows also decreases slightly. (4) The village landscape is mainly spatially “clustered,” concentrated in the center and southern part of the village, with a few “dots” distributed in the east and northwest, and the overall trend is spreading from the center to the periphery. (5) The evolution of village landscapes is influenced by a combination of human factors, including demographic, economic, and policy factors, as well as natural geographic factors, such as topography, climate change, and precipitation. The study provides theoretical support and practical guidance for the sustainable development of Zahan Village, as well as valuable experience and inspiration for the optimal development of other minority villages
Spatial distribution and its driving forces analysis of soil organic matter in semi-arid grassland open-pit mining areas
No full textStudying the spatial distribution of soil organic matter (SOM) and exploring its driving factors in semi-arid grassland open-pit coal mining areas is crucial for sustaining ecological development and security. Currently, research on SOM in mining areas lacks large-scale investigation, sampling, spatial distribution, and driving force research for semi-arid grassland open-pit coal mining areas, and it is unable to comprehensively grasp the distribution characteristics and driving force of SOM in open-pit coal mines. In view of this, this study took the Shengli Coal Field in Xilinhot City, the hinterland of Xilingol Grassland, as an example to research the spatial distribution and driving forces of SOM in the semi-arid grassland open-pit coal mining area. The results show that: (1) Areas with high SOM content were mainly distributed in the north of open-pit germanium mine, west No. 2 open-pit mine, and No. 1 open-pit mine. Areas with low SOM content were mainly distributed on the east and southeast sides of the city. From the spatial distribution perspective, mining has a certain impact on SOM in the study area. (2) Natural factors have a higher impact on SOM changes than human factors. The order of influence degree of each factor on the spatial distribution of SOM is NDVI > Water > Agriculture > Mine > Town > Industry. The sources of influence on SOM in the research area are relatively complex. (3) The interaction between two factors presents two relationships: nonlinear enhancement and dual-factor enhancement. A single factor is lower than the interaction between various factors. In the interaction between factors, the explanation rate of interaction between Town, Agriculture, Mine, NDVI, Water, and all other factors is above 0.85. This study has important practical significance for soil management in mining areas, ecological restoration, and planning of national land space, etc
Do Chinese government policies affect performance of real estate enterprises?
No full textThe Chinese central government has instituted a series of macro-economic tightening and easing policy measures on the real estate industry to stabilize the housing market in recent decades. However, our understanding of these policies and their impact on real estate firms is limited. This paper constructs an index of government policies on the real estate industry by collecting national housing policies in China from 2007 to 2019. We use this index to quantify the impact of government policies on real estate enterprises’ performance, based on data from 103 real estate enterprises listed on the Chinese A-share market. Two important conclusions are drawn from the panel data regression. First, tightened real estate policies significantly lower real estate enterprises’ profitability (ROA and ROE), while increase their liquidity risk. Second, the heterogeneity analysis shows that the tightened real estate policies yield downward impact more mildly on state-owned real estate enterprises than non-state-owned enterprises
A dynamic performance-based payment mechanism for Public-Private Partnership projects: An integrated model for principal-agent and multi-objective optimization models
No full textPerformance-based payment mechanism is one of the key issues to ensure all stakeholders’ benefits in infrastructure Public-Private Partnership (PPP) projects. However, most existing research on performance-based payment with a fixed incentive coefficient can’t play a good incentive role. This study aims to the intrinsic mechanism between the performance appraisal score and the performance-based payment structure, so as to design the dynamic performance-based payment mechanism for infrastructure PPP projects. Firstly, the multi-objective optimal method is used to calculate the unit-payment. Second, principal-agent theory is used to construct the performance-based payment model with a changeable incentive coefficient. The findings of this study show that, the performance-based payment mechanism can effectively motivate participants to provide high-quality and efficient services, because their remuneration directly depends on their performance. When the outcome does not meet expectations, the amount paid can be adjusted accordingly, thus ensuring the maximum protection of public resources as well as the private sector’s profits. They serve a dual purpose, on one hand, they offer insights to rectify the shortcomings in the current unsatisfactory payment structure. On the other hand, the study provides a theoretical reference for the public sector to effectively incentivize the private sector in enhancing project performance
Urban housing prices and consumption structure upgrading: Different relationships in urban and rural China
No full textThe dynamics of housing prices can play a pivotal role in shaping household behavior. Motivated by the limited research on the impact of housing prices on consumption structure upgrading in China, this paper presents a series of analyses that deploy panel data from 276 Chinese cities between 2005 and 2019 to scrutinize this impact. Firstly, fixed effect models were used to investigate the relationship between urban housing price and the consumption structure upgrading, and it was found that urban housing price has an inverted U-shaped effect on the consumption structure upgrading of Chinese urban residents, while it has an inhibitory effect on the consumption structure upgrading of Chinese rural residents. Then, we conducted multiple robustness tests, all of which corroborated the benchmark results’ reliability. Finally, deeper than existing research, the mechanism of the impact of urban housing prices on the consumption structure upgrading was further explored and it was found that increasing urban housing prices can affect consumption structure upgrading by affecting residents’ marginal propensity to consume in development and enjoyment. Our findings provide key alternatives for China’s government to promote residents’ consumption structure upgrading