Relative Curves Research Articles

ESG and debt structure: Is the nature of this relationship nonlinear?

The relationships between environment, social, and governance (ESG) scores and debt structure are examined using the two-stage least square model with annual data from Chinese listed firms over the 2011–2020 period. The research results suggest that the ESG composite scores and long-term debt have a U curve based nonlinear relationship. The results are robust to endogeneity concerns, alternative regression model specifications, alternative ESG scores, and after controlling for additional variables. In addition, the relationship between debt maturity and S scores (but not the E and G scores) is significant in the nonlinear model. Second, the effect of ESG on long-term debt is stronger for firms within polluting industries when compared to firms in less polluting industries. Third, the effect of ESG on long-term debt is stronger when economic policy uncertainty is low. Fourth, dynamic effect investigations show that ESG activities generate long-term effects on debt maturity. Finally, an inverse U curve relationship between ESG scores and cost of debt is documented. All these results are consistent with the well-established trade-off theory. Policy wise, firms should pay attention to the S dimension when considering debt structure, and to the economic policy environment when considering the impact of ESG activities on debt structure. Academic research can focus on verifying whether these results are generalizable across countries and the stage of economic development of markets investigated.

Street-level urban heat island mitigation: Assessing the cooling effect of green infrastructure using urban IoT sensor big data

With the growing interest in mitigating urban heat islands (UHIs), the cooling effects of green infrastructure (GI) have been extensively studied. Despite its importance, there is limited exploration of how GI improves street-level outdoor thermal comfort (OTC) for pedestrians. This study addresses this gap by examining how urban greenery and water bodies help alleviate Outdoor Thermal Comfort derived Urban Heat Islands (OTC-UHIs). Our study results indicate that GI significantly mitigates the OTC-UHIs in hot-humid summer conditions. Highly developed urban areas exhibit smaller land surface temperature differences between day and night due to high heat capacity in buildings and pavement, creating a tropical nighttime phenomenon. GI's cooling effects are greater in areas with higher vegetation cover, leading to a decrease in the OTC-UHI's intensity, frequency, and duration. The relationship between OTC-UHIs and urban morphology varies throughout the day, with vegetation cover ratio and sky view factors impacting cooling significantly. Additionally, cooling impact distance of GI follows a power curve relationship, with parks having a longer cooling impact distance compared to rivers, particularly at night. Our findings highlight that the effective usage of GI can significantly improve the street-level OTC of pedestrians by tackling the climate-induced UHIs.

Moderate operation scales of agricultural land under the greenhouse and open-field production modes based on DEA model in mountainous areas of southwest China

The identification of the moderate scale of agricultural land was recognized as one of the key measures promoting sustainable agriculture development. However, due to the research gap in mountainous areas, new agricultural business entities (NABE) in these areas usually either refer to the plain area or simply pursue large scale, resulting in low production efficiency and even posing a threat to their sustainable survival. In this study, the Data Envelopment Analysis (DEA) model and Tobit regression model tools were employed to quantitatively reveal the moderate scale and key driving factors of agricultural land under the scale operation modes of greenhouse and open-field types. It was based on 154 NABE questionnaires in the mountainous areas around the Sichuan Basin in China, where NABEs are flourishing. The findings show an approximately "inverted U-shaped" curve relationship between NABE's production efficiency and their planting scale. The primary reason for the failure of NABE to achieve an overall high level of production efficiency is scale inefficiency. The optimal scale intervals for the greenhouse and open-field types of scale operation modes are 3.0–4.3 ha and 3.3–5.0 ha, respectively. Business entities' age, land circulation scale, land rent, and agricultural insurance are common factors that influence the scale efficiencies of both the greenhouse and open-field types. Accordingly, policy interventions regarding the guidance of moderate-scale operation of agricultural land are proposed for achieving the dual goal of cultivating NABE and implementing the Rural Revitalization Strategy in mountainous areas of China. While contributing to the knowledge on scale efficiency of agricultural land, this research also enlightens the practice of policy-making targeted to the sustainable development of agricultural industry led by NABE worldwide.

Schumpeterian endogenous growth model under green innovation and its enculturation effect

This paper studies the economic system in which the preference of enterprises and residents to practice green behavior becomes a common form. This economic system shall be referred to as the economic system under the green development pattern, this paper divides its development stage into two parts: the green development transformation stage and the green innovation stage. As the system transitions from the former stage to the latter, the innovation system composed of quality innovation and variety innovation will transition to an innovation system with three innovation modes: quality innovation, variety innovation and green innovation. In the green innovation stage, green innovation is transformed into endogenous elements of the economic system, which requires a study of the endogenous growth model and growth law, in light of new endogenous elements. This paper establishes the Schumpeterian endogenous growth model under the green development pattern (hereafter the Green Schumpeterian Model). This new model takes green innovation into account and combines the growth rate of residents' green behavior awareness level, the green discount rate, and the penetration rate of green innovation. The research findings indicate that green innovation leads to the economic enculturation effect and the environmental enculturation effect in the economic system under the green development pattern, achieving explosive in economic growth and environmental protection. Under the green development pattern, there is a new spatial Kuznets curve relationship between pollution emissions, the green innovation level, and the output level. The point at which pollution emissions reach their peak represents the turning point of the spatial Kuznets curve. Furthermore, by reducing the green discount rate and increasing the growth rate of residents' green behavioral awareness level, a nonlinear positive impact can be observed on the explosive mechanism of green innovation.

Impacts of Land Urbanization on CO2 Emissions: Policy Implications Based on Developmental Stages

The systematic advancement of land urbanization coupled with the pursuit of a low-carbon economy constitutes a critical challenge faced by numerous nations across the globe. Utilizing panel data spanning 195 countries from 1990 to 2020, this study employed a panel regression model to scrutinize the impact mechanisms of land urbanization on CO2 emissions across income groups. The findings revealed a consistent overall increase in both land urbanization and per capita CO2 emissions during the period examined, with marked disparities evident among countries of varying income levels. The regression analysis further identified an “inverted U-shaped” curve relationship between land urbanization and per capita CO2 emissions in the global context and within high-income panels. Conversely, a “U-shaped” curve relationship was discerned in lower-middle-income nations, whereas a linear relationship was observed in upper-middle-income and low-income countries. These insights serve to deepen the understanding of the CO2 emission implications of land urbanization across countries at different development stages. This study underscores the necessity for countries to attentively consider their unique stage of development when devising CO2 reduction policies, reinforcing the complex interplay between urbanization, economic categorization, and environmental stewardship.

Investigation of the Rock-Breaking Mechanism of Drilling under Different Conditions Using Numerical Simulation

The interaction between the drill bit and rock is a complex dynamic problem in the process of drilling and breaking rock. In this paper, the dynamic process of drilling and breaking rock is analyzed using ABAQUS software. The rock-breaking mechanism of drilling is revealed according to the stress–strain state of the rock and the force of the drill bit. The effect of the size of the drill bit and the characteristics of the rock mass on the drilling parameters is studied during the drilling process. The results show that both thrust force and torque show a linear increase with the increasing drilling speed under each fixed rotational speed. The drill bit size has minimal impact on the correlation coefficient of the relationship curves between thrust force, torque, and rotation speed. The drilling results in a soft–hard interlayered rock formation show that there are significant differences in thrust force and torque during the drilling process of different rock types. Whether transitioning from a soft rock layer to a hard rock layer or vice versa, the relationship between thrust force and torque is distinctly manifested whenever there is a change in rock quality. The thrust force and torque increase correspondingly with the increase in confining pressure. When subjected to lateral pressure, thrust force and torque gradually increase with the rising confining pressure. Vertical drilling exhibits a larger increase in thrust force and torque compared to horizontal drilling. The thrust force and torque increase more significantly with the rise in confining pressure compared to lateral pressure.

Lateral Torsional Buckling Strength Analysis of Single Symmetric I-Beam Section

The common beam sections in the engineering field are mostly double symmetrical I-beams, It’s advantage is that the design and analysis are double symmetric geometry, therefore simpler. The monosymmetric I-shaped section is relatively in line with engineering requirements and material economy, the reason is that the main design basis for the strength of the I-shaped section is the influence of the section geometry on the compression side. This study focuses on different monosymmetric sections, Its area contrast (A) is 1, 1.33, 1.46, 1.5 and 1.99 respectively. The relationship between the ratio of the five section enlarged wing plates and the nominal bending strength (Mn). monosymmetric section is divided into plastic, inelastic and elastic three intervals for analysis and comparison. Area contrast of 1 is bisymmetric section, magnifications from 1.33 to 1.99 are different magnifications for pressure flanges, area contrast 1.99 relative double symmetry area increased by 1.3 times, strength increased by a factor of 1.2 in the plastic zone, the inelastic interval increases by 2.2 times, the elastic range increases by 3.8 times, increasing the compression flange area can increase the strength of the section in the plastic, inelastic and elastic ranges. in this study, the area contrast is analyzed as the 1.46 intensity change point, abrupt slope changes in intensity occur in area contrast to-intensity curves. Through the above analysis method, the study adopts the AISC 2017 specification to analyze the single symmetrical flange section of the I-beam, discuss the strength difference of the enlarged ratio of the compression side, and establish the strength relationship curve of each section, and propose the single symmetrical I-shaped section with the best benefit.

Estimation of stress–strain constitutive model for ultra-high performance concrete after high temperature with an deep neural network based method

In order to better study and analyze the residual compressive behavior and stress–strain curve relationships of ultra-high performance concrete (UHPC) materials after high temperatures, high-temperature tests and uniaxial compression tests were carried out on 144 specimens in the temperature range of 20 °C-900 °C in this paper. The effects of different curing regimes and cooling regimes on the mechanical properties, apparent characteristic and stress–strain curves of UHPC after experiencing different temperatures were investigated respectively. As the target temperature increased, the stress–strain curves of all UHPC specimens gradually tended to be flatten, the peak point of the curve shifted to the right, the peak strain increased sharply, and the elastic modulus and proportional limits gradually decreased. The compressive strength and modulus of toughness of the UHPC specimens both increased and then decreased as the target temperature increased, with a critical temperature of 300 °C and 500 °C respectively. The Poisson's ratio of the UHPC specimens decreased and then increased as the target temperature increased, with a critical temperature of 500 °C. In addition, based on the experimental results, a Deep Neural Network (DNN) model with four hidden layers and 100 neurons in each layer was constructed to predict the complete residual stress–strain response of UHPC materials after high temperature. The training and validation of the DNN model was completed by pre-processing and segmenting the original dataset with the help of Pytorch deep learning libraries. The DNN model predicts stress–strain curves that are in excellent agreement with the UHPC test curves.

An insight into the effect of primary hidden microfissures on mechanical behaviors and failure characteristics of brittle basalt

The anisotropy of mechanical properties of hard rocks is usually affected by the internal primary hidden microfissure structures, which tend to induce secondary rock fracture propagation even surrounding rock instabilities in deep underground excavation. This research attempts to reveal the control effect of primary hidden microfissures on the mechanical behaviors and failure characteristics of cryptocrystalline basalt with hidden microfissures (CBWHM) through a series of laboratory tests. Firstly, a geometric feature extraction method for primary hidden microfissures of basalt rock has been proposed, by which 20 groups of three-dimensional (3D) visualization models of cylindrical basalt samples were established, and the distribution location and volume crack rate (KV) of hidden microfissures were simultaneously determined. On this basis, a series of the uniaxial compression tests of basalt samples with synchronous acoustic emission (AE) were carried out. Results show that the location and development degree of primary hidden microfissures significantly control the mechanical characteristics of basalt, with the relevant micro-fracture events occurring earlier and throughout the whole loading process compared with intact samples. In general, there exists a uniaxial polynomial fitting relationship between the strength of basalt samples and KV. The larger the KV, the lower the peak strength (σc) of basalt, which could decrease by 30–50% compared to that of the intact rock when KV is more than 5‰. However, when the hidden microfissures with large dip angles are located close to the central axis, the influence of KV on the rock strength becomes less, but the crack propagation and failure morphology are still obviously controlled by the hidden microfissures. The statistical analysis results of surface cracks and rock fragment characteristics of the damaged basalt samples further show that the basalt rock is easy to expand, penetrate and eventually fail along the hidden microfissures under loading, and it is tensile fracture that controls the failure of CBWHM. With an increase of KV, the mass percentage (W) of the coarse particle of the sample fragments increases gradually, and the fractal dimension (D) of the rock fragments and KV of the hidden microfisures show an obvious logarithmic curve relationship. The research could provide effective guidance for the interpretation of the meso-mechanism of hard rock failures.

Simulation Experiment and Teaching Research of a Land-Based Ship Engine Room

In order to make up for the shortage of scientific research experiments and teaching in land-based engine room laboratory, a simulation system is designed and developed using B/S mode to simulate scientific research experiments, teaching and operation processes, and designed algorithms to simulate the propulsion characteristics of the main propulsion diesel engine. A large number of experiments were carried out, and the relationship curve between output power and fuel consumption rate of the main engine was obtained in the laboratory. Apache JMeter was used to test the pressure of the simulation system deployed in Dalian Maritime University Cloud. It is found that under the test conditions, the average response time of sample request is 330 ms, which is far superior the design standard of 2 s. There is no abnormal response to all requests, and all indicators fully meet the requirements of the project team. The simulation system fills the gap in the application of panoramic interactive technology in Marine engineering education, and provides a reference for the exploration of "intelligent +" experiment and teaching mode in maritime university laboratories.

Study on Chloride Diffusion Behaviors of Recycled Concrete of Random Aggregates

Based on the chloride ions (Cl−) diffusion model and aggregate grading theory, PYTHON and COMSOL are used to construct a mesoscopic model of recycled concrete random polygon aggregate and verify its validity in combination with existing experimental results. The diffusion law of Cl− in recycled concrete and the law of influence of critical factors on the Cl− erosion resistance are studied by calculating and analyzing the Cl− erosion resistance of recycled concrete under different working conditions such as the diffusivity of new and old mortar, the thickness of old mortar and the replacement ratio of recycled aggregate. The results show that the simulation results agree well with the test results, and the method can better reproduce the Cl− diffusion process inside the recycled concrete. There are discontinuous features based on the relationship curves between the Cl− concentration and the depth of the recycled concrete. The Cl− concentration inside the concrete gradually increases with the increase of the diffusion rate of the old and new mortars. The resistance behavior of the recycled concrete to Cl− attack decreases with the increase of the thickness of the old mortar.

Simulation for the Superconductor Linear Eddy Current Brake of the High-Speed Train

A kind of superconductive coil was designed as the linear eddy current brake for the Electric Multiple Units (EMU). 2D and 3D simulations were carried out on the designed coils. The 2D simulation results showed that the generated braking force could reach 10kN when the train speed was between 28m/s and 110m/s. The simulation results indicated that the reduced gap between the coil and the railway, the increased pole distance, and the increased coil quantity would bring more braking force. The relationship curve between speed and braking force was also investigated during the 2D simulation. The speed of 28m/s and 110m/s was applied with the 3D simulation based on the 2D results. Both the magnetic inducting intensity and the current 180A could meet the requirements of the chosen superconducting wire.

Epidemiological application of the cycle threshold value of RT-PCR for estimating infection period in cases of SARS-CoV-2

Epidemiological control of coronavirus disease 2019 (COVID-19) is needed to estimate the infection period of confirmed cases and identify potential cases. The present study, targeting confirmed cases for which the time of COVID-19 symptom onset was disclosed, aimed to investigate the relationship between intervals (day) from symptom onset to testing the cycle threshold (CT) values of real-time reverse transcription-polymerase chain reaction. Of the COVID-19 confirmed cases, those for which the date of suspected symptom onset in the epidemiological investigation was specifically disclosed were included in this study. Interval was defined as the number of days from symptom onset (as disclosed by the patient) to specimen collection for testing. A locally weighted regression smoothing (LOWESS) curve was applied, with intervals as explanatory variables and CT values (CTR for RdRp gene and CTE for E gene) as outcome variables. After finding its non-linear relationship, a polynomial regression model was applied to estimate the 95% confidence interval values of CTR and CTE by interval. The application of LOWESS in 331 patients identified a U-shaped curve relationship between the CTR and CTE values according to the number of interval days, and both CTR and CTE satisfied the quadratic model for interval days. Active application of these results to epidemiological investigations would minimize the chance of failing to identify individuals who are in contact with COVID-19 confirmed cases, thereby reducing the potential transmission of the virus to local communities.

Study on development methods of different types of gas wells in tight sandstone gas reservoirs

Reasonable production allocation of tight sandstone gas reservoirs is an important basis for efficient development of gas wells. Taking Block XX in Ordos Basin as an example, the modified flowing material balance equation was established considering the variation of gas viscosity and compression coefficient, the advantages and disadvantages of the method were discussed, and a reasonable production allocation process for gas wells was developed. The results show that: ① The commonly used flow material balance method ignores the change of natural gas compression coefficient, viscosity and deviation coefficient in the production process. The slope of the relationship curve between bottom hole pressure and cumulative production and the slope of the relationship curve between average formation pressure and cumulative production are not equal After considering this change. Compared with the results calculated by the material balance method, the results calculated by the flow material balance method are smaller. ② The production of 660 gas wells in the study area during stable production period is verified. Compared with the open flow method, the dynamic reserve allocation method is better, with an error of 0.06%. ③ The new method in this paper is used to allocate production for different types of gas wells. The cumulative production of different types of gas wells shows different degrees of increase. The I, II, III and IV types of gas wells increase by 32.26%, 30.29%, 23.58% and 25.07% respectively. This study provides technical support for dynamic reserve calculation and reasonable production allocation of gas wells in the study area, and has important guiding significance for the formulation of reasonable development plan and economic and efficient development of tight sandstone gas reservoirs.

Exploring carbon sequestration in broad-leaved Korean pine forests: Insights into photosynthetic and respiratory processes

A comprehensive understanding of carbon assimilation and sequestration in broad-leaved Korean pine forests is crucial for accurately estimating this significant aspect of temperate forests at a regional scale. In this study, we introduced a high-temporal resolution model designed for carbon assimilation insights at the plot scale, focusing on specific parameters such as leaf area dynamics, vertical leaf distribution, photosynthetically active radiation (PAR) fluctuations, and the photosynthetic traits of tree species. The findings reveal that most tree species in broad-leaved Korean pine forests exhibit an inverted U-shaped pattern in leaf area dynamics, with shorter leaf drop periods than leaf expansion events. Leaf distribution varies significantly among different canopy heights, with approximately 80 % of the leaves above 15 m. PAR decreases as canopy height decreases, with PAR at 25 m accounting for about 60 % of the PAR above the canopy. Our framework incorporates a leaf-scale light-response curve and empirical photosynthesis-temperature relationships to estimate forest carbon assimilation on daily and hourly scales accurately. Using the model, we assess the gross primary productivity (GPP), leaf net photosynthetic assimilation (LNPA), and carbon increment (ΔC) of broad-leaved Korean pine forests from 2017 to 2020. The results demonstrate GPP, LNPA, and ΔC values of 21.4 t·ha−1·a−1, 17.4 t·ha−1·a−1, and 4.0 t·ha−1·a−1, respectively. Regarding efficiency, GPP, LNPA, and ΔC per square meter of leaf per year are 179 g, 146 g, and 33 g, respectively. Notably, tree species in the canopy layer of the forest exhibit significantly higher efficiency than those in the understory layer. This research significantly contributes to our understanding of carbon cycling and the responses of forest ecosystems to climate change. Moreover, it provides a practical tool for forest management and the development of carbon sequestration strategies.

Experimental and Numerical Study on Progressive Collapse of the Midcolumn in a Glulam Timber Frame Exposed to Fire

This paper presents experimental and numerical investigations on the progressive collapse behavior of a two-story glulam frame when the middle column is exposed to ISO834 standard fire. The stress characteristics, temperature distributions, and deformation relationship curves of the bottom middle column after a fire are obtained. The collapse resistance performance and the mechanism of the glulam structure under local fire are studied in combination with the failure mode of the frame. The experimental results show that the failure time of the middle column in fire is 16.8 min, and the time to determine the progressive collapse of the structure is 17.17 min when the rotation angle exceeds the limit. The structure can remain stable for some time after the failure of the fire column, but as the fire continues to spread, the structure will collapse further. In addition, a temperature-field analysis model with the grid element type of DC3D8 and a structural field analysis model with the grid element type of C3D8R was established by using ABAQUS software under the experimental conditions. The numerical simulation is carried out by means of thermal–mechanical sequential coupling. The numerical simulation results show that the temperature of the beam end rose to more than 300 °C in about 15 min although it was not directly exposed to fire. The temperature of the whole connector at the pillar foot in the bottom column reached more than 700 °C when the fire time reached 60 min. The numerical simulation results agree well with the experimental results. The analysis results show that, in the failure process of the fire column, the junction of beam ends begins to produce stretching force to form a catenary effect. As the fire time increases, the catenary effect eventually fails. The stretching force at the beam end rapidly decreases and withdraws from the work, causing the progressive collapse of the frame.

Research on Characteristics of Economic Development and Environmental Pollution in Typical Energy Regions

The data on economic development quality and environmental pollution intensity from 2001 to 2021 was selected by taking Shanxi province, a typical energy region of the country, as the research object was analyzed in the evolution characteristics of economic development quality and environmental pollution intensity in Shanxi province over the past two decades by using linear regression, numerical fitting, and Pearson correlation coefficient, and was explored on their mutual relationship. The results show that Shanxi province has made long-term progress in economic development since 2001, with GDP increasing nearly 10 times and maintaining an average annual growth of about 7%. The main pollutants in the last 20 show a trend of steady change, first ascending and then descending, with the turning point occurring in the 12th Five-Year Plan period (2011–2015), which shows that the environmental policies and investments made by China and Shanxi governments in the last 10 years of the new era have taken effect. The results of the numerical fitting curve suggest that the per capita GDP shows a classical inverted “U” curve relationship with wastewater and SO2 emissions, respectively. The turning point occurs at around 20,000 yuan per capita GDP, while the relationship between chemical oxygen demand and ammonia nitrogen emissions is monotonically decreasing. The relationship with solid waste generation is monotonically increasing without the turning point. The results of the correlation analysis further supported the conclusion of the fitted curve.

Fire and post-fire performance of blind-bolted concrete-filled steel tubular joints with restrained steel beams: Experiment and simulation

Blind-bolted connection is a type of new developed prefabricated beam-column connection, which can be used to connect the concrete filled steel tubular (CFST) columns and the steel beams easily. The static and dynamic performance of CFST column to steel beam joints with blind-bolted connections have been well explored, but limited research has been conducted to investigate the fire and post-fire performance of this type of composite joint. In this paper, a series of reversed T-shaped joint fire tests were conducted to investigate the fire and post-fire performance of blind-bolted CFST joints with axially restrained steel beams. The influence of restrained effect from adjacent members in the entire frame structure on the response of blind-bolted joints in and after fire could be reasonably considered by the reversed T-shaped joint fire test. The joint temperature, failure modes, beam and column displacements and temperature internal force development during the entire loading and fire stage were recorded and discussed. The test results indicated that the blind-bolted connections showed very good working performance in and after fire, and no bolt shank fracture or bolt pull-out failure was observed. Finite element analysis (FEA) models were established to simulate the fire and post-fire performance of blind-bolted CFST T-shaped joints with axially restrained steel beams, and the joint moment versus relative rotation angle relationship curves of the blind-bolted joints during the entire fire and loading process were extracted and discussed based on the FEA models. The results indicated that the joint negative moment generated by the axially restrained beam boundary in the heating and cooling phases could go up to around 1.4 times the joint negative moment at ambient temperature.

Enhancing Density Prediction of Agricultural Land Soil through Void Area Curve Analysis

Thresholding is a digital image analysis method used to distinguish objects from the background in images and it is mainly used for void and density analysis in soil. It is important to select an appropriate thresholding method because the accuracy of void analysis can vary significantly depending on the threshold value; however, there is currently no standard for soil density analysis. Therefore, this study proposes an image analysis method for soil density prediction. The experimental process involved collecting soil samples from agricultural lands, encompassing various soil textures including sandy loam, loam, silt loam, and silty clay loam. These samples were then meticulously prepared under controlled conditions, ensuring a comprehensive range of dry densities and water content levels. Digital images of the soil samples were acquired using a Canon EOS100d camera, employing a high-resolution setup that provided precise imaging capabilities. The porosity of the soil image is calculated by various thresholding methods. Based on the analysis results, we propose a void area curve, a new approach that can be applied to the soil density prediction. The void area curve is the relationship curve between the threshold value and porosity of the soil image. The standard deviation of the void area curve showed a high correlation with the dry density of the soil. The standard deviation of the void area curve was used to predict the dry density under various soil texture and water content conditions, and the RMSE was 0.037 t/m3. The method of estimating soil density with the standard deviation of the void area curve can be used more generally than the existing analysis method because there is no need to select a specific threshold value.

Effects of planting density on test weight and related indexes of maize

AbstractMaize (Zea mays L.) is an important food crop in the world. Reasonably increasing planting density is an important way to increase maize yield. Test weight (TW) determines the classification and affects market price. In order to clarify the influence and mechanism of planting density on TW, in this study, a 2‐year field experiment was carried out in Tongliao, Inner Mongolia Autonomous Region in 2019 and 2020. Four widely planted maize hybrids and six planting densities (6.0, 7.5, 9.0, 10.5, 12.0, and 13.5 × 104 plants ha−1) were tested, using drip irrigation water and fertilizer integration. The output parameters measured were grain yield, TW, thousand‐kernel weight (TKW), kernel volume, kernel density (KD), kernels per unit volume (KPV), and kernel packing efficiency. The result showed that yields ranged from 12.04 to 16.58 ton ha−1and TW ranged from 751 to 807 kg m−3, which exceeded the requirements for classification as first‐grade maize (720 kg m−3). Both yield and TW have a quadratic curve relationship with planting density, but the planting density corresponding to the two indicators is different when they reach the maximum value. With the increase in planting density, the TKW decreased and KPV increased, which made the relationship between TW(y) and planting density (x) and expressed as y = ax2 + bx + c. Planting density had a significant influence on TW and the relationship between TW and planting density was consistent under growth years and maize varieties. Considering the economic benefits, the planting density corresponding to the maximum yield is strongly recommended for future maize production.