Predicting Bank Failures: A Synthesis of Literature and Directions for Future Research

Risk management has been a topic of great interest to Michael McAleer. Even as recent as 2020, his paper on risk management for COVID-19 was published. In his memory, this article is focused on bankruptcy risk in financial firms. For financial institutions in particular, banks are considered special, given that they perform risk management functions that are unique. Risks in banking arise from both internal and external factors. The GFC underlined the need for comprehensive risk management, and researchers since then have been working towards fulfilling that need. Similarly, the central banks across the world have begun periodic stress-testing of banks’ ability to withstand shocks. This paper investigates the machine-learning and statistical techniques used in the literature on bank failure prediction. The study finds that though considerable progress has been made using advanced statistical and computational techniques, given the complex nature of banking risk, the ability of statistical techniques to predict bank failures is limited. Machine-learning-based models are increasingly becoming popular due to their significant predictive ability. The paper also suggests the directions for future research.

ELASTOPLASTIC PROBLEM FOR PERFORATED PLATE IN TRANSVERSE SHEAR

A solution is given to the problem of transverse shear of a thin plate clamped along the edges of the holes and weakened by a doubly periodic system of rectilinear through cracks with plastic end zones collinear to the abscissa and ordinate axes of unequal length. General representations of solutions are constructed that describe the class of problems with a doubly periodic stress distribution outside circular holes and rectilinear cracks with end zones of plastic deformations. Satisfying the boundary conditions, the solution of the problem of the theory of shear plates is reduced to two infinite systems of algebraic equations and two singular integral equations. Then each singular integral equation is reduced to a finite system of linear algebraic equations. Keywords: perforated thin plate, straight cracks with end zones, transverse bending, plastic deformation zones.

Identification and Expression Analysis of Stress Responsive Genes in Lentil (Lens culinaris)

Plants during their growth, experience periodic stress conditions both abiotic (adverse environmental conditions) as well as biotic (infection by pathogens). They appear to respond to these adverse conditions by modulating the expression of many genes. One of the pronounced effects of stress on plant is the enhanced synthesis of a set of proteins-termed ' stress proteins'. Lentil contains asset of genes/proteins which helps this crop to overcome abiotic stresses. In the present study, HSP70 (Heat Shock Protein), LEA (Late Embryogenesis Abundant) and Aldolase genes were identified and cloned in pTZ57RT vector followed by sequencing. Expression analysis was done through Q-PCR which was assessed by using cDNA from all the heat, drought and salinity stressed and unstressed lentil cotyledons. The highest level of transcript of HSP70 was realized upon exposure to heat at 45°C for 3 hour followed by at 45°C for 2 hour and lowest at 40°C for 1hour. LEA gene was identified under drought and salinity stress and highest transcript was at 20% PEG for 3 hour (drought stress) and in salinity stress highest transcript was at 150 mm for 6 hour. For Aldolase gene highest transcript was recorded after 3, 6 and 12 hr at 100 mM, 150 mM, 200 mM of salinity stress respectively. From these studies it can be concluded that heat shock protein gene, LEA, and aldolase present in lentil which can be exploited in overcoming the abiotic stresses for obtaining the higher productivity in crop plants through genetic engineering.

Transient Stress Distribution and Failure Response of a Wellbore Drilled by a Periodic Load

The poroelastodynamic failure of a wellbore due to periodic loading during drilling is an unsolved problem. The conventional poroelastic method to calculate the stress distribution around wellbore is for static loading cases and cannot be used for short-time dynamic-loading cases which result in wave propagation in the formation. This paper formulates a poroelastodynamic model to characterize dynamic stress and pressure wave due to periodic loadings and to analyze the transient failure of the suddenly drilled wellbore in a non-hydrostatic stress field. The fully coupled poroelastodynamic model was developed based on the equations of motion, fluid flow and constitutive equations to reflect stress and pressure waves that resulted from a periodic stress perturbation at the wellbore surface. The model was analytically solved by means of field expansions of the solutions, by performing a Laplace transform as well as some special techniques. Simulation results show that the pressure and stress responses inside the formation resemble a damped oscillator where the amplitude decays as the distance to wellbore increases. Especially the potential shear failure zone around the wellbore was computed and plotted. Influences of poroelastic parameters, in-situ stress and periodic load parameters on the shear failure responses were analyzed in a detailed parametric study, and the results provide fundamental insights into wellbore stability maintenance in different reservoirs.

Rubber Surface Change and Static Charging under Periodic Stress

Rubber materials play an important role in robotics, due to their sensing and actuating abilities, that are exploited in soft smart materials endowed with shape-adaptive and electroadhesive properties. The application of an electric field produces non-linear deformation that has been extensively modelled, but is not understood at the molecular level. The symmetric effect (the production of an electric field due to rubber deformation) was recently discovered and explained as follows: rubber surface chemical composition and adsorptive properties change during rubber deformation, allowing the surface to exchange charge with the atmosphere. The present work describes the complex surface morphology and microchemistry of tubing made from vulcanized natural rubber, showing that it is rough and made from two domain types: stiffer elevations containing Br or Al (depending on the sample used) and O, that rise above an elastic base that is exempt of elements other than C and H. The surface area fraction occupied by the elastic base is higher in the strained rubber than when it is relaxed. Electrostatic potential on rubber surfaces was measured as a function of the stretching frequency, using Kelvin electrodes and showing frequency-dependent potential variation. This is explained considering charge exchange between the atmosphere and rubber surface, mediated by water vapor adsorbed in the stretched rubber and trapped when it relaxes.

Fabrication of Multimeasurand Sensor for Monitoring of a Li-Ion Battery

This paper details the fabrication and testing of a combined temperature and expansion sensor to improve state of charge (SOC) and state of health (SOH) estimation for Li-ion batteries. These sensors enable the characterization of periodic stress and strain changes in the electrode materials of Lithium-ion batteries during the charge and discharge process. These ultrathin sensors are built on a polyimide substrate which can enable direct integration between cells without compromising safety or cell cooling design. Leveraging the sensor design and fabrication process used to create inductive coil eddy current (EC) sensors for crack detection, these sensors were characterized on three Panasonic 5 A-h cells showing the capability to measure expansion of Li-ion batteries. By sensing the intercalation effects, which cause cell expansion, improvements in estimation of SOH and SOC can be enabled through the use of physics-based battery models, which combine the thermal, mechanical, and electrochemical aspects of its operation.