Search results

The purpose of this study was to introduce three-dimensional printing (3DP) of functionally graded sandwich foams (FGSFs). This work was continued by predicting the mechanical buckling and free vibration behavior of 3DP FGSFs using experimental and numerical analyses.

Initially, hollow glass microballoon-reinforced high-density polyethylene-based polymer composite foams were developed, and these materials were extruded into their respective filaments. These filaments are used as feedstock materials in fused filament fabrication based 3DP for the development of FGSFs. Scanning electron microscopy analysis was performed on the freeze-dried samples to observe filler sustainability. Furthermore, the density, critical buckling load (P_cr), natural frequency (f_n) and damping factor of FGSFs were evaluated. The critical buckling load (P_cr) of the FGSFs was estimated using the double-tangent method and modified Budiansky criteria.

The density of FGSFs decreased with increasing filler percentage. The mechanical buckling load increased with the filler percentage. The natural frequency corresponding to the first mode of the FGSFs exhibited a decreasing trend with an increasing load in the pre-buckling regime and an increase in post-buckled zone, whereas the damping factor exhibited the opposite trend.

The current research work is valuable for the area of 3D printing by developing the functionally graded foam based sandwich beams. Furthermore, it intended to present the buckling behavior of 3D printed FGSFs, variation of frequency and damping factor corresponding to first three modes with increase in load.

This study aims to deal with developing composite filaments and investigating the tribological behavior of additively manufactured syntactic foam composites. The primary objective is to examine the suitability of the cenosphere (CS; 0–30 Wt.%) to develop a high-quality lightweight composite structure with improved abrasion strength.

CS/polyethylene terephthalate glycol (PETG) composite feedstock filaments under optimized extrusion conditions were developed, and a fused filament fabrication process was used to prepare CS-filled PETG composite structures under optimal printing conditions. Significant parameters such as CS (0–30 Wt.%), sliding speed (200–800 rpm) and typical load (10–40 N) were used to minimize the dry sliding wear rate and coefficient of friction for developed composites.

The friction coefficient and specific wear rate (SWR) are most affected by the CS weight percentage and applied load, respectively. However, nozzle temperature has the least effect on the friction coefficient and SWR. A mathematical model predicts the composite material’s SWR and coefficient of friction with 87.5% and 95.2% accuracy, respectively.

Because of their tailorable physical and mechanical properties, CS/PETG lightweight composite structures can be used in low-density and damage-tolerance applications.

CS, an industrial waste material, is used to develop lightweight syntactic foam composites for advanced engineering applications.

CS-reinforced PETG composite filaments were developed to fabricate ultra-light composite structures through a 3D printing routine.

Many industries use non-Newtonian ternary hybrid nanofluids (THNF) because of how well they control rheological and heat transport. This being the case, this paper aims to numerically study the Casson-Williamson THNF flow over a yawed cylinder, considering the effects of several slips and an inclined magnetic field. The THNF comprises Al₂O₃-TiO₂-SiO₂ nanoparticles because they improve heat transmission due to large thermal conductivity.

Applying suitable nonsimilarity variables transforms the coupled highly dimensional nonlinear partial differential equations (PDEs) into a system of nondimensional PDEs. To accomplish the goal of achieving the solution, an implicit finite difference approach is used in conjunction with Quasilinearization. With the assistance of a script written in MATLAB, the numerical results and the graphical representation of those solutions were ascertained.

As the Casson parameter β increases, there is an improvement in the velocity profiles in both chord and span orientations, while the gradients Re1/2Cf,Re1/2C¯f reduce for the same variations of β. The velocities of Casson THNF are greater than those of Casson-Williamson THNF. Approximately, a 202% and a 32% ascension are remarked in the magnitudes of Re1/2Cf and Re1/2C¯f for Casson-Williamson THNF than the Casson THNF only. When velocity slip attribute S1 jumps to 1 from 0.5, magnitude of both F(ξ,η) and Re1/2Cf fell down and it is reflected to be 396% at ξ=1, Wi=1 and β=1. An augmentation in thermal jump results in advanced fluid temperature and lower Re−1/2Nu. In particular, about 159% of down drift is detected when S2 taking 1.

There is no existing research on the effects of Casson-Williamson THNF flow over a yawed cylinder with multiple slips and an angled magnetic field, according to the literature.

The purpose of this paper is to examine how a firm’s investment behavior relates to its subsequent bank loan contracting.

Using a sample of US firms during the period 1992-2011, the authors examine the association between overinvestment (underinvestment) and three characteristics of bank loan contracts: loan spread, collateral requirement, and loan maturity.

The authors find that overinvesting firms obtain loans with higher loan spreads. Additional tests show that the effect of overinvestment on loan spreads is generally more pronounced in firms with lower reputation, weaker shareholder rights, and lower institutional ownership. The effect of overinvestment on collateral requirement is mixed, and investment efficiency has no significant relation to loan maturity.

The results are subject to the following caveats. First, while the study provides empirical evidence that investment efficiency affects bank loan contracting terms, especially the cost of bank loans, the underlying theory is not well-developed. The authors leave it up to future research to provide a theoretical framework to clearly distinguish the cash flow and credit risk effects of past investment behavior from those of existing agency conflicts. Second, due to data limitation, the sample size is small, especially when the authors control for corporate governance measured by G-index and institutional ownership.

The finding that overinvestment is costly to corporations suggests that managers should consider the potential trade-offs from such investment decisions carefully. The evidence also alerts shareholders and board members to the importance of monitoring management investment decisions. In addition, the authors find that corporate governance moderates the relationship between investment decisions and cost of bank loans, suggesting that it would be beneficial to design effective governance mechanisms to prevent management from empire building and motivate managers to pursue efficient investment strategies.

First, the findings enhance understanding of the potential economic consequences of overinvestment decisions in the context of a firm’s private debt contracting. The evidence suggests that lenders perceive higher credit risk from overinvestment than from underinvestment, likely because firms squander cash in the current period by investing in (negative net present value) projects that are likely to result in future cash flow problems. Second, the study contributes to the literature on the determinants of bank loans by identifying an observable empirical proxy for uncertainty in future cash flows that increases credit risk.

This study examines the impact of firm-bank relationships on bank loan spreads and the mitigating role of firm credit ratings on that impact.

The study sample consists of Indonesian publicly listed companies for the period 2006 to 2016; bank-loan data was extracted from the Loan Pricing Corporation Dealscan database. For the degree of firm-bank relationships, the data on each loan is manually computed, using five different methods taken from Bharath et al. (2011) and Fields et al. (2012). All of the regression analyses are controlled for the year fixed effects, heteroscedasticity, and firm-level clustering. To address the endogeneity issues, this study uses several methods, including partitioning the sample, running nearest-neighbour and propensity score matching tests, and using instrumental variables in two-staged least-squares regression models.

In line with relationship theory and in opposition to the hold-up argument, this study finds that lending relationships reduce bank loan spreads and that the impact is more noticeable among non-rated Indonesian firms. Specifically, each additional unit in the total number of years of a firm-bank relationship and the number of previous loan contracts with the same bank are associated with 7.34 and 9.15 basis-point decreases, respectively, in these loan spreads.

Corporations and banks should maintain close, long-term relationships to reduce the screening and monitoring costs of borrowing. Regulators should create public policies that encourage banks to put more emphasis on relationships in their lending practices, especially in relation to crisis-prone companies.

To the best of the authors’ knowledge, this is the first study to examine the impact of lending relationships on bank loan spreads in Indonesia. The study offers insights on banking relationships in emerging markets with concentrated banking industries, underdeveloped capital markets and prominent business-group affiliations.

The paper investigates whether stock liquidity of firms is valued by lending banks revealing that firms with higher liquidity in the capital market pay lower spreads for the loans they obtain. This relationship is causal as evidenced by using the decimalization of tick size as an exogenous shock-to-stock liquidity in a difference-in-differences setting. Reduction in financial constraint and improvement in corporate governance induced by higher stock liquidity are potential mechanisms through which liquidity impacts loan spreads. These higher liquidity firms also receive less stringent nonprice loan terms, for example, longer loan maturity and less required collateral.

The authors examine how the major board reforms recently implemented by countries around the world affect firms' choice of debt.

Using a quasi-experimental setting of major board reforms around the world that aim to improve board-related governance practices in various areas, this study investigates the impact of effective board monitoring on corporate debt choice. The authors employ difference-in-differences-type quasi-natural experiment method and path analysis for hypotheses testing.

The authors find that the implementation of board reforms is positively associated with firms' preference for public debt financing over bank debt. However, this effect tends to weaken after the fourth year following the implementation of board reforms. In additional analyses, the authors find that “rule-based” reforms have a more pronounced effect on firms' choice of debt than do “comply-or-explain” reforms. Both (1) strengthened firm-level internal governance practices that address concerns about the agency cost of debt and (2) reduced information asymmetries play important roles in facilitating firms' debt choice, but the evidence suggests that the former is the economic mechanism through which country-level reforms affect corporate debt choice.

The study extends the literature examining the heterogeneity of corporate debt choices in a global setting and the literature on the consequences of corporate governance reforms.

The findings demonstrate the effectiveness of the corporate board reforms implemented in countries around the world, addressing concerns from critics about their potential harm or ineffectiveness.

The results indicate that country-level board reforms reduce the extent to which shareholder–creditor conflicts harm shareholders.

This study aims to examine whether debt financing creates incentives for private firms to engage in earnings management via classification shifting. Especially, the authors examine whether debt-induced financial reporting incentives differ depending on the type of debt (i.e. public bonds versus private loans) and whether such incentives are influenced by the characteristics of external auditors (i.e. initial audits and auditor size).

The study uses data on 93,427 Korean private firms from 2001 to 2016. Classification shifting is measured by the positive correlation between non-core expenses and unexpected core earnings estimated with ordinary least squares.

The empirical analyses reveal that private firms engage in classification shifting as do public firms. Importantly, classification shifting is observed only in private firms that have outstanding debt, but not in private firms without debt. Among debt-financing private firms, classification shifting is more prevalent for firms that issue public debt than for firms that only use private debt. In addition, classification shifting of debt-financing private firms is more successful when they are audited by new auditors that are one of the non-Big 4 firms.

The study provides evidence of classification shifting in private firms, which is novel to the literature. However, the inferences in the study depend on the validity of the model for detecting classification shifting.

This study helps lenders enhance their understanding on the financial reporting behaviors of borrowing firms. The results in this study suggest that lenders should be cautious in using core earnings for their investment decisions.

This study contributes to the literature by providing novel evidence of classification shifting in private firms. In addition, the authors contribute to the literature on debt-induced incentives for financial reporting.

Country image determines consumers’ beliefs toward the country’s products, through halo effect. While the relevant literature is predominantly focused on the context of well-known products from traditionally leading exporters, the purpose of this paper is to examine the two levels of halo effect (i.e. country image as halo and a well-known product category as halo) on a less-known product category from a recently developed country.

The purpose of study was carried out by using a quantitative approach. Survey responses were collected from 253 US consumers who are aged between 18 and 67 years. This study only examined South Korea and used the two selected product categories (i.e. cell phones and apparel) as samples for the study.

The results of a series of regression analyses confirmed that the positive images of South Korea and Korean cell phones served as halo, thereby enhancing the respondents’ beliefs toward Korean apparel, which is a less-known product category that they have not yet experienced. Further, the respondents’ positive beliefs toward both cell phones and apparel increased their purchase intentions of those two products.

The findings of this study imply that the general country image and the country’s well-known product images are critical in introducing the country’s less-known product to foreign markets.

The originality of this study lies in its unique focus on relatively less-known product category of a recently developed country (i.e. Korean apparel), which received limited attention in the past research. This study is also one of the few attempts to examine the role of a country’s well-known products on the country’s less-known products, another level of halo effect in country image.

β-Carotene is the most appropriate and significant precursor of vitamin A. Synthetic carotene supplements have been known to pose a threat to human health, making natural sources such as the indefensible choice for the production and extraction of carotene.

This study considers Blakeslea trispora, a filamentous fungus, as a source of production of carotenoids by fermentation and wet and dry mycelium were used to analyse and obtain better extraction results.

In this study, natural oils such as soy oil and cottonseed oil were incorporated into fermentation media to increase the production of carotene. For the optimization process, Plackett–Burman and one-factor-at-a-time (OVAT) models were identified as being of great value.

OVAT was carried out for corn starch because it plays a major role in the production of carotene and the corn starch at 30 g/L concentration has shown the maximum activity of 3.48 mg/gm. After optimizing process variables, submerged fermentation was eventually carried out under highly controlled media conditions. The resulting product was quantified using UV spectroscopy and extraction of carotene has been observed in the presence of various solvents. Among a range of solvents used, the methylene Di chloride produced-carotene at 86% recovery at a significantly lower temperature of 35°C.