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Overuse of chemical fertilizers and pesticides is a major policy concern for many countries. Chinese government has adopted many technologies and management practices to reduce their use. However, little is known about the effects of social-economic method such as short supply chain (SSC) participation. SSC is an important organizational innovation in fresh food supply chains aiming at directly connecting farmers and consumers. Closer relationships between farmers and consumers may result in production behavioral changes. Thus the purpose of this paper is to investigate the impacts of SSC participation on agrochemicals application.

Based on the household level data collected from Jiangsu province in China, this paper employs an instrumental variable (IV) method to address the self-selection bias when we evaluate the effects of SSC participation on use of chemical fertilizer and pesticides. In addition, this paper also distinguishes between growth inputs and facilitating inputs in the production function when we calculate the marginal production values of chemical fertilizer and pesticides.

The empirical results show that SSC participation significantly reduces chemical fertilizer use by 351 kg and pesticides costs by 1659 Yuan (RMB) per hectare, accounting for 43.4% of the average chemical fertilizer use and 49.4% of the average pesticide costs, respectively for Chinese vegetable farms. However, SSC participation still cannot improve the use efficiency of agrochemicals.

This paper uses both application quantities and allocation efficiencies of chemical fertilizer and pesticides to comprehensively evaluate the effects of SSC participations. The results will reveal the core role of SSC played in promoting sustainable development of Chinese agricultural sector dominated by small-scale farmers.

The objective is to have a better understanding of the impacts of the COVID-19 pandemic on food supply chain in Wuhan.

Through a simplified flow, the authors qualitatively analyze the impacts of the COVID-19 pandemic on food supply chain. Data was gathered through a telephone survey of food suppliers in Wuhan.

The prevention measures of the COVID-19 pandemic had negative impacts on food supply chain in Wuhan. About 83.1% of food suppliers experienced a decrease in revenues. This is influenced by factors including food category on sale, purchase channel of food, food supplier's household registration and the number of the COVID-19 patients in the located community.

Due to the limitation of available data, there is a lack of quantitative analysis on the impact on food supply chain. The sample size of food suppliers is limited.

This study identifies the challenges in the food supply chain resulting from the control measures implemented during the COVID-19 pandemic in Wuhan and provides a reference for the design of control measures in other regions.

This study supplements the literature regarding the impact of public health emergencies such as the COVID-19 pandemic on food supply chain, especially food suppliers' revenues.

The primary objective of this study is characterizing the anisotropic mechanical properties of corrugated cardboard and simultaneously simulating its drop cushioning dynamic effects under various drop conditions.

Static and dynamic tests were conducted on corrugated cardboard to obtain adequate experimental data in different directions. An effective anisotropic constitutive model is introduced by developing the honeycomb materials model in ANSYS LS-Dyna, and an effective approach is established toward effectively determining the material parameters from the test data obtained. The model is validated by comparing simulation results with experimental data from five drop conditions, including bottom drop, front drop, side drop, 30° side drop and edge drop. Additionally, simulations are conducted to study the cushioning performance of the packaging by dropping the corrugated cardboard at different heights.

The study establishes a fast and effective approach to simulating the drop cushioning performance of corrugated cardboard under various drop conditions, which demonstrates good agreement with experimental data.

This approach is of value for packaging protection and provides guidance for stacking of packaging during transportation.

A direct and unified approach is proposed toward simultaneously simulating large strain elastic behaviors of gellan gels with different gellan polymer concentrations. The purpose of this paper is to construct an elastic potential with certain parameters of direct physical meanings, based on well-designed invariants of Hencky’s logarithmic strain.

For each given value of the concentration, the values of the parameters incorporated may be determined in the sense of achieving accurate agreement with large strain uniaxial extension and compression data. By means of a new interpolating technique, each parameter as a function of the concentration is then obtained from a given set of parameter values for certain concentration values.

Then, the effects of gellan polymer concentrations on large strain elastic behaviors of gellan gels are studied in demonstrating how each parameter relies on the concentration. Plane-strain (simple shear) responses are also presented for gellan gels with different polymer concentrations.

A direct, unified approach was proposed toward achieving a simultaneous simulation of large elastic strain behaviors of gellan gels for different gellan polymer concentrations. Each parameter incorporated in the proposed elastic potential will be derived as a function of the polymer concentration in an explicit form, in the very sense of simultaneously simulating large strain data for different concentrations.

A new approach is proposed toward accurately matching any given realistic hardening and softening data from uniaxial tensile test up to failure and moreover, toward bypassing usual tedious implicit trial-and-error iterative procedures in identifying numerous unknown parameters.

Finite strain response features of metals with realistic hardening-to-softening transition effects up to eventual failure are studied for the first time based on the self-consistent elastoplastic J₂-flow model with the logarithmic stress rate. As contrasted with usual approximate and incomplete treatments merely considering certain particular types of hardening effects such as power type hardening, here a novel and explicit approach is proposed to obtain a complete form of the plastic-work-dependent yield strength over the whole hardening and softening range.

A new multi-axial evolution equation for both hardening and softening effects is established in an explicit form. Complete results for the purpose of model validation and prediction are presented for the finite strain responses of monotonic uniaxial stretching up to failure.

New finite strain elastoplastic equations are established with a new history-dependent variable equivalently in place of the usual plastic work. With these equations, a unified and accurate simulation of both gardening and softening effects up to failure is achieved for the first time in an explicit sense without involving usual tedious implicit trial-and-error iterative procedures.