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Implementing green innovation is crucial for firms to build or sustain competitive advantages within the context of the sustainable development goals. Academic research has broadly explored how firms can induce green innovation behavior (GIB), examining external factors, but few studies in the current literature have deeply investigated unabsorbed slack as an internal antecedent of GIB. Drawing upon the behavioral theory of the firm and integrating it with dynamic capabilities theory, this study aims to address this deficiency by investigating the impact of unabsorbed slack on GIB and the mediating roles of two dimensions of capability reconfiguration: capability evolution and capability substitution in the relationship between unabsorbed slack and GIB. Furthermore, this study also discusses the moderating effects of consumer green pressure on the relationship between unabsorbed slack and capability evolution/substitution.

Survey data were collected from 286 Chinese technology-intensive manufacturing firms to empirically test the relationships among the variables.

The results reveal that unabsorbed slack has a positive influence on GIB. Furthermore, capability evolution and substitution both play mediating roles in the relationship between unabsorbed slack and GIB. Comparative analysis showed that the mediating effect of capability substitution is stronger than that of capability evolution. Moreover, consumer green pressure strengthens the positive relationship between unabsorbed slack and capability evolution/substitution.

This study enriches the research on the driving forces of GIB and contributes to providing managerial implications for firms to launch green innovation activities.

This study aims to evaluate the effectiveness of three-dimensional (3D) printed foam polylactic acid (PLA) patterns in reducing ceramic shell stresses and cracking during burnout in the rapid investment casting (RIC) process to improve casting yield and dimensional tolerances.

Cylindrical and step-wedge patterns were 3D printed using foam PLA feedstock and compared with patterns from plain PLA and Polyvinyl Butyral (PVB). The patterns were shelled using ceramic slurry and investment cast in A356.1 aluminum alloy. Shell cracking and dimensional tolerances of resulting castings were assessed. Additionally, a complex component was 3D printed, laser-scanned, then cast and rescanned to evaluate dimensional accuracy. Finite Element Analysis (FEA) was conducted on cylindrical geometries to analyze internal mold pressure because of thermal stresses during burnout.

The foam PLA for all patterns produced no shell cracking during both ramp and flash burnouts. Castings made from foam PLA patterns showed improved dimensional tolerances and a narrower error distribution in GD&T analysis compared to those made from PLA and PVB. FEA results indicated that the thermomechanical properties of foam PLA reduce internal mold pressure by over 90%, which decreased internal shell stresses.

This research introduces a novel application of 3D printed foam PLA feedstock in the RIC process as a pattern material. This study demonstrates that foam PLA patterns effectively eliminate shell cracking during burnout and enhance dimensional accuracy. The findings of this study offer a new approach for improving dimensional tolerances and casting yield in RIC, which has not been previously explored.

The purpose of this paper is to mesoscopically analyze the impact of parameter variations in the random pore structure on the stress distribution of layered-porous sintered silver used in high-power electronics, and to conduct a variable importance analysis of the parameter variations in the random pore structure.

Sintered silver, featuring a porous structure, improves thermal and mechanical performance by effectively absorbing stress and facilitating heat dissipation. To ensure the performance and scalability of layered-porous sintered silver, this paper uses Gaussian random fields to model the random pore structure and performs a sensitivity analysis on pore characteristic length and porosity, both of which significantly impact the stress distribution within the sintered silver layer. First, multiple sets of random pore models with varying characteristic lengths and porosities were generated using Gaussian random fields. Then, the maximum stress of the sintered silver layer containing random pores under power cycling conditions was extracted. Finally, the Morris screening method was used to perform a sensitivity analysis on the variables of the random pore structure that affect the maximum stress in the sintered silver layer. The systematic evaluation of the parameter variations in the random pore structure was conducted to assess their impacts on the maximum stress in the sintered silver layer.

Due to the high randomness of the pore structure generated by the Gaussian random field function, the maximum stress in the sintered layer fluctuates with different mesoscopic models. After systematic evaluation using the Morris screening method, it was found that the maximum stress in the sintered silver layer is most sensitive to the variation in the pore characteristic length in the x-direction. Reducing the length of pores in the x-direction can significantly decrease the stress concentration between pores in the sintered silver layer after power cycling.

This paper innovatively uses a Gaussian random field to model the mesoscopic structure of layered-porous sintered silver for high-power electronics, and applies the Morris screening method to perform variable importance analysis on the stress distribution results within the sintered silver layers. The mesoscopic study demonstrates that the maximum stress in the sintered silver layer is most sensitive to changes in the pore characteristic length in the x-direction.

The main objective of this experimental work is to analyze and measure the form tolerances namely flatness and squareness while machining a meso deep hole in EDM on Inconel-718 material plate.

The experiments were performed on 15 amps rated SPARKONIX-EDM as per DOE (design of experiments). Kerosene was used as a dielectric along with constant pressure of 0.2 kg/cm² for all trial runs. The currents T_on and T_off were selected as process constraints to conduct experimental trials. The MRR, EWR, machining time and form tolerances were considered as output responses. The experimental outcomes were optimized by hybrid optimization using Taguchi and GRA (grey relational analysis) method.

The EDM process parameters for Ni-based super alloy namely Inconel-718 had optimized by using GRA method coupled with Taguchi method. The optimum solution has been calculated for MRR, EWR, machining time and form tolerances namely squareness and flatness. The optimized parameters for the output responses in EDM process are Peak current (Ip) 12 Amps, 400 µs T_on (pulse on time) and 10 µs T_off (pulse off time). An attempt had also been made to attain Max. and Min. Evaluation of MRR and form tolerances, respectively. The attained optimum outcomes had also been examined through a real experiment and established to be satisfactory.

This article will facilitate the defense, aerospace and EDM industries to improve their productivity with closer tolerances.

The optimized parameters by multi-parametric optimization showed the considerable improvement in the process and will facilitate the defense, aerospace and EDM industries to improve their productivity with closer tolerances.

Rainy-day savings have been an effective measure for maintaining financial stability in times of emergency. Motivated by the rapid expansion of cryptocurrencies, the present study examines how crypto investments could moderate the beneficial outcomes of rainy-day savings for alleviating financial anxiety during the most recent economic turbulence caused by the COVID-19 pandemic.

The present study carries out multivariate logistic regression with interaction effects on the most recent 2021 cohort data from the National Financial Capability Study (NFCS).

While rainy-day savings relate to less financial anxiety, the effect varies depending on whether an individual has invested in cryptocurrencies. Specifically, this paper finds that crypto investors experience less relief in financial anxiety from rainy-day savings than non-crypto investors. Additionally, crypto investors are more susceptible to financial stressors like job loss and financial fragility, likely due to the financial loss from investing in cryptocurrencies.

The findings highlight the necessity of implementing policies and regulations, such as the newly approved Markets in Crypto-Assets (MiCA) regulation, that could raise people’s awareness of the high-risk nature of cryptocurrencies as well as offering targeted financial education for crypto investors, especially during times of market downturn.

This is the first attempt to study how crypto investments may weaken the benefits of rainy-day savings in reducing financial anxiety. The findings offer new insights into the beneficial outcomes of rainy-day savings for emergencies in light of individual crypto investment backgrounds. Additionally, findings from the present study also contain important implications given the rapid expansion of the cryptocurrency market as well as future economic turbulence.

Biotechnology is closely associated to microfluidics. During the last decade, designs of microfluidic devices such as geometries and scales have been modified and improved according to the applications for better performance. Numerous sensor technologies existing in the industry has potential use for clinical applications. Fabrication techniques of microfluidics initially rooted from the electromechanical systems (EMS) technology.

In this review, we emphasized on the most available manufacture approaches to fabricate microchannels, their applications and the properties which make them unique components in biological studies.

Major fundamental and technological advances demonstrate the enhancing of capabilities and improving the reliability of biosensors based on microfluidic. Several researchers have been reported verity of methods to fabricate different devices based on EMS technology due to the electroconductivity properties and their small size of them. Therefore, controlled fabrication method of MEMS plays an important role to design and fabricate a highly selective detection of medical devices in a variety of biological fluids. Stable, tight and reliable monitoring devices for biological components still remains a massive challenge and several studies focused on MEMS to fabricate simple and easy monitoring devices.

This paper is not submitted or under review in any other journal.

The purpose of this paper is to obtain the nonlinear Schrodinger equation (NLSE) numerical solutions in the presence of the first-order chromatic dispersion using a second-order, unconditionally stable, implicit finite difference method. In addition, stability and accuracy are proved for the resulting scheme.

The conserved quantities such as mass, momentum and energy are calculated for the system governed by the NLSE. Moreover, the robustness of the scheme is confirmed by conducting various numerical tests using the Crank-Nicolson method on different cases of solitons to discuss the effects of the factor considered on solitons properties and on conserved quantities.

The Crank-Nicolson scheme has been derived to solve the NLSE for optical fibers in the presence of the wave packet drift effects. It has been founded that the numerical scheme is second-order in time and space and unconditionally stable by using von-Neumann stability analysis. The effect of the parameters considered in the study is displayed in the case of one, two and three solitons. It was noted that the reliance of NLSE numeric solutions properties on coefficients of wave packets drift, dispersions and Kerr nonlinearity play an important control not only the stable and unstable regime but also the energy, momentum conservation laws. Accordingly, by comparing our numerical results in this study with the previous work, it was recognized that the obtained results are the generalized formularization of these work. Also, it was distinguished that our new data are regarding to the new communications modes that depend on the dispersion, wave packets drift and nonlinearity coefficients.

The present study uses the first-order chromatic. Also, it highlights the relationship between the parameters of dispersion, nonlinearity and optical wave properties. The study further reports the effect of wave packet drift, dispersions and Kerr nonlinearity play an important control not only the stable and unstable regime but also the energy, momentum conservation laws.

The application of galvanized steel is widespread across industries due to its protective zinc coating that protects against atmospheric corrosion. However, previous studies have primarily focused on long-term corrosion rates rather than the full-scale corrosion behavior of the zinc. This paper aims to study the full-scale corrosion evolution of galvanic steel under simulated marine atmospheric environment using real-time EIS measurement.

Electrochemical impedance spectroscopy (EIS) provides an advanced method in monitoring such behavior. Therefore, the EIS method has been used to conduct a comprehensive investigation on the corrosion behavior of galvanic steel in a full-time manner.

The results indicate that the corrosion process of galvanic steel can be divided into three stages: an initial stage with an increased corrosion rate, a subsequent stage with a reduced corrosion rate, and finally a third stage with the lowest and constant corrosion rate. The evolution of corrosion resistance is closely related to changes in composition and structure of the patina layer. In the initial stage, galvanized steel undergoes the formation of soluble ZnCl₂ and needle-like Zn₅(OH)₈Cl₂·H₂O, which promotes the generation and maintenance of an electrolyte layer, consequently leading to an increase in corrosion rate. With prolonged corrosion time, there is a continuous accumulation of Zn₅(OH)₈Cl₂·H₂O within the patina layer, which reduces the content of soluble components and promotes the development of a denser inner layer, thus enhancing corrosion resistance.

This work holds significance in the monitoring of corrosion, understanding the evolution of corrosion and predicting the lifespan of galvanized steel.

This article’s indented contribution is to provide novel theoretical insights and empirical observations on “who gets what” in the way of incomes, including wages. The article challenges the conventional wisdom about stratification, especially power and status, as an outcome or function of economic distribution. It posits that income distribution is conditional on pre‐existing social stratification expressed in antecedent differences in class, power, status and related factors.

This paper aims to revel the leakage characteristics of the bent-axis piston pump considering elastohydrodynamic deformation via a dynamic leakage model.

A dynamic leakage model of bent-axis piston pump based on elastohydrodynamic lubrication theory is proposed, which is used to present the leakage characteristics of bent-axis piston pump. The model is composed of three parts. First, the dynamic gap in the piston ring-cylinder bore interface (PRCB) is described via the elastohydrodynamic lubrication equations. Then, the PRCB leakage is presented based on the dynamic gap. Finally, combined with leakage equation of the valve plate-cylinder block interface (VPCB), the total leakage model is proposed. Through the numerical simulation and experiment, the leakage characteristics of bent-axis piston pump considering elasto-hydrodynamic deformation are studied.

The PRCB leakage is negatively correlated with VPCB leakage under the range of 800–1400 r/min and 1–25 MPa. When the discharge pressure is less than the critical pressure, the PRCB leakage is the main factor affecting the total leakage in bent-axis piston pump. On the contrary, the VPCB leakage is the main factor. The critical pressure increases with increasing speed

The effect of operating parameters has a significant effect on the elastic deformation of piston ring without considering wear of friction pairs in bent-axis piston pump. There is a critical phenomenon in the leakage, which is related to the operating parameters, and provides a novel idea for extracting wear information from leakage and evaluating the status of bent-piston pump.