Budapest University of Technology and Economics

Couples can be Tractable: New Algorithms and Hardness Results for the Hospitals/Residents Problem with Couples

Abstract We study the Hospitals/Residents problem with Couples ( hrc ), where a solution is a stable matching or a report that none exists. We present a novel polynomial-time algorithm that can find a near-feasible stable matching, where hospitals’ capacities are adjusted by at m...

Full counting statistics in the sine-Gordon model

Full counting statistics (FCS) is a dynamical generalisation of the free energy, encapsulating detailed information about the distribution and large-scale correlation functions of conserved charges and their associated currents. In this work, we present a comprehensive numerical...

Robust stability and surface error assessment in interrupted turning under spindle speed variation

Abstract Predicting stability in turning becomes especially difficult when the process combines interrupted cutting with spindle-speed variation (SSV). The resulting time-dependent delays and discontinuous dynamics call for advanced numerical tools beyond conventional chatter ana...

Fractional Bessel–Sobolev and Bessel B-potential spaces

After proving the equivalence of the Bessel $K$-functional and the corresponding spherical modulus of smoothness we define fractional Bessel–Sobolev spaces. As an analog of the classical one the imbedding relation of fractional Bessel–Sobolev and Bessel B-potential spaces is poin...

Bike-sharing station profiles and urban context: Understanding imbalance with asymmetry-based clustering

Depicting the usage characteristics of a bike-sharing system can contribute to more efficient planning and operation. Station-level imbalances are typically treated as operational defects to be corrected. However, the systematic asymmetries between pick-ups and drop-offs may refl...

A bound on the equivariant unknotting number

Abstract We study how the equivariant signature of strongly invertible knots changes when one of the Boyle–Chen equivariant crossing change moves is applied. It follows from our results that the absolute value of the equivariant signature introduced by Alfieri–Boyle gives a lower...

Informed questioning on NOVA and Nutri-Score interpretation in augmented virtuality sensory evaluation

Abstract Ultra-processed foods and front-of-pack labelling systems are important in consumer food decision-making, yet processing-related and nutrition-related information may be interpreted differently. This study investigated whether informed questioning using NOVA classificati...

Intrinsic volumes of the quantum state space and mutually unbiased bases

Abstract Previous studies on the geometrical properties of the state space of a finite-level quantum system have determined its volume and surface area. Building on this foundation, we derive explicit formulas for two additional intrinsic volume quantities. The question of whethe...

Kids These Days! A Cross-Temporal Meta-Analysis of Changes in Emotional and Behavioral Problems of Population-Based Samples Over the Past Decades

Abstract There is a general belief that mental health problems are increasing in younger generations, though little objective comparisons exist. The current meta-analysis examines changes in subclinical mean-level overall symptom burden and shifts in specific domains among popula...

Three-parameter bifurcation scenarios in a minimal mechanical model with LuGre friction

Abstract The LuGre friction model is among the most frequently used models in multibody dynamical applications. It is common that the steady-state conditions of the model are described by a specific shape of the Stribeck characteristic, which is influenced by the Stribeck exponen...

The Discourse-Directive Function of Loci in the Argument Model of Topics

Abstract In argumentation theory, loci - also referred to as topoi - are commonly viewed as abstract sources of inference that guide the invention of arguments. Within the Argument Model of Topics (AMT), loci are analysed as sources of inference underlying individual arguments. T...

Development of Flame Retarded Battery Casings Using Glass Fiber‐Reinforced Epoxy Resin

ABSTRACT This study investigates the development of glass fiber‐reinforced epoxy resin composites with enhanced fire performance for application in electric vehicle battery casings. A low‐viscosity epoxy system incorporating phosphorus‐, inorganic‐, and nitrogen‐based (PIN) flame...

Distribution network hosting capacity evaluation through a novel Power Index concept

Accelerating integration of distributed renewables is straining distribution networks, where voltage rise and thermal overloads emerge once hosting capacity is exceeded. A novel Power Index (PI) is introduced that unifies voltage and loading margins into a single, interpretable i...

Applications of the pattern evolution research: modelling the evolutionary dynamics of historical script systems

Abstract Pattern systems are abstract communication frameworks composed of symbols, syntactic rules, and semantic structures. This study introduces the theoretical foundations of Deep Feature Phylogenetics as a model-free approach to the evolution of symbolic systems. Unlike trad...