Research works

Enhancing instance discrimination for self-supervised adversarial training

A learning machine is prone to be attacked by adversarial examples in presence of imperceptible perturbations. Adversarial training (AT) is developed to build a defense model against the adversarial attacks. Most of the previous works were conducted in supervised setting. To rele...

Greenland's Topography Triggers Cyclogenesis: Synergy Between Lee Cyclogenesis and Jet Streak

Abstract Arctic cyclones play a crucial role in shaping Arctic weather patterns and influencing sea ice concentrations. During the Multidisciplinary Drifting Observatory for the Study of Arctic Climate expedition in April 2020, an Arctic cyclone was observed at the leeside of Gre...

Activated carbon production from apple orchard woody waste using a fluidized bed reactor with freezing pretreatment to establish a local circular economy system

Waste is always associated with all activities, and world population growth has caused a significant increase in its production ratio. Improper management of this material can have serious consequences for the environment and; consequently, human life. Agricultural activities are...

Clustering thermograms of Schubert autographs based on chain and laid line features

Abstract We propose a novel approach towards the automated clustering of handmade paper. Specifically, we acquired a large dataset of thermographic images and developed a feature extraction and automated clustering method to identify leaves of paper made with the same mold. Our m...

Transfer Learning of CATE with Kernel Ridge Regression

The proliferation of data has sparked significant interest in leveraging findings from one study to estimate treatment effects in a different target population without direct outcome observations. However, the transfer learning process is frequently hindered by substantial covari...

Spatiotemporal Variation of Vegetation and Its Responses to Climate Change in Pakistan

Abstract Changes in vegetation cover and its relationship with climate factors are crucial for ecosystem stability, especially in arid and semiarid regions like Pakistan. However, the impact of temperature and precipitation fluctuations on vegetation dynamics in these regions rem...

Cervical cancer screening predictors in Tanzania: a variance component models’ approach of national survey 2022

Despite the potential for prevention through early detection and treatment, cervical cancer remains the most prevalent cancer among women of reproductive age (WRA). There is a paucity of evidence on the predictors influencing cervical cancer screening nationwide. Thus, this study...

A Simple and Adaptive Confidence Interval when Nuisance Parameters Satisfy an Inequality

Inequalities may appear in many models. They can be as simple as assuming a parameter is nonnegative, possibly a regression coefficient or a treatment effect. This paper focuses on models with one inequality and proposes an inequality-imposed confidence interval (IICI) that has p...

Splitting rational incomplete Mackey functors

Inspired by equivariant homotopy theory, equivariant algebra studies generalisations of G G -Mackey functors that do not have all transfer maps (also known as induction maps), for G G a finite group. These incomplete Mackey functors have interesting and subtle properties that are...

Strong Embeddings of 3-Connected Cubic Planar Graphs on Surfaces of non-negative Euler Characteristic

Whitney proved that 3-connected planar graphs admit a unique embedding on the sphere. In contrast, Enami investigated embeddings of 3-connected cubic planar graphs on non-spherical surfaces with non-negative Euler characteristic. He established that such an embedding exists if an...

Optimal Consumption Under Loss-Averse Multiplicative Habit Formation Preferences

Abstract. This paper studies a loss-averse version of the multiplicative habit formation preference and the corresponding optimal investment and consumption strategies over an infinite horizon. The agent’s consumption preference is depicted by a general S-shaped utility function...

Campana rational connectedness and weak approximation

Campana introduced a notion of Campana rational connectedness for Campana orbifolds.Given a Campana fibration over a complex curve, we prove that a version of weak approximation for Campana sections holds at places of good reduction when the general fiber satisfies a slightly str...

Determining the optimal design characteristics of trapezoidal piano key weirs for improved water discharge

Abstract This study attempts to evaluate the influence of design factors and flow characteristics on the discharge capacity of trapezoidal piano key weirs. To evaluate the influence of the main design factors on discharge rates, 9 models were simulated, with width ratios of 1.25,...

Coloring Grids Avoiding Bicolored Paths

The star chromatic number on a graph is the minimum number of colors in a proper vertex coloring forbidding any $P_4$ with two colors (bicolored). This problem was introduced by Grünbaum (1973) together with the acyclic coloring of graphs, where bicolored cycles are avoided. In t...

Gender roles and identity at Chiribaya Alta, Peru: A multiple correspondence analysis of mortuary contexts

Gender is an important structuring social identity, but archaeologists continue to struggle with non-binary ways to approach gender in the past. This study uses grave good presence and absence to examine the nature of gender roles and gender identity at Chiribaya Alta, Peru. Mult...

Principal component analysis in Bayes spaces for sparsely sampled density functions

This paper presents a novel approach to functional principal component analysis (FPCA) in Bayes spaces, where densities are the object of analysis, but only few individual samples from each density are observed. We use the observed data directly to account for all sources of unce...

Strong Spatial Mixing for Colorings on Trees and its Algorithmic Applications

Strong spatial mixing (SSM) is an important quantitative notion of correlation decay for Gibbs distributions arising in statistical physics, probability theory, and theoretical computer science. A longstanding conjecture is that the uniform distribution on proper q -colorings on...

Two new species of Pavania (Acari: Heterostigmata: Dolichocybidae) associated with scarab beetles (Coleoptera: Scarabaeidae) from Tanzania and Madagascar

Khaustov, Alexander A., Frolov, Andrey V. (2022): Two new species of Pavania (Acari: Heterostigmata: Dolichocybidae) associated with scarab beetles (Coleoptera: Scarabaeidae) from Tanzania and Madagascar. Persian Journal of Acarology 11 (4): 545-558, DOI: 10.22073/pja.v11i4.76531

Likelihood‐Based Inference With Separable Correlation Matrices

ABSTRACT This paper proposes methods for likelihood‐based inference in multivariate linear regressions when the correlation matrix of the responses is separable; that is, it has a Kronecker product structure, but the variances are unrestricted. The methods are enabled by a block‐...

Automorphism groups of rigid affine surfaces: The identity component

It is known that the identity component of the automorphism group of a projective algebraic variety is an algebraic group.This is not true in general for quasi-projective varieties.In this note, we address the question as to when, given an affine algebraic surface Y , the identit...