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Found 6278 publications

Assessing the impact of household energy efficiency and renewable energy developments on energy poverty reduction

Galyna Trypolska Iryna Sotnyk Tetiana Kurbatova Oleksandra Kubatko Tetiana Perederii Liliana Śmiech

Publication Name: Environmental Economics

Publication Date: 2025-01-01

Volume: 16

Issue: 4

Page Range: 83-94

Description:

The paper aims to develop and adapt an econometric model for assessing and forecasting the impact of household energy efficiency and renewable energy deployment on reducing energy poverty in Ukraine. Due to the lack of updated statistical data after 2022 caused by the war, the adapted model was tested using pre-war data from the State Statistics Service of Ukraine and the World Bank for 2002-2021. As access to some prewar datasets was also restricted for security reasons in Ukraine, proxy indicators were applied, allowing adaptation to limited information conditions. The modeling results showed that a 1,000 USD increase in GDP per capita reduces the share of the population living below the national poverty line and, accordingly, the energy-poor population, by 3%. Conversely, a 1% increase in gross capital formation raises the energy poverty level by 0.5%, indicating no direct impact of investment in physical capital, including expenses on energy-efficiency measures, on household welfare. Household expenditures on utilities and the share of renewable energy in total energy consumption were found to be statistically insignificant. The study confirms that household income remains the dominant determinant of energy poverty, while improvements in energy efficiency and renewable energy development play supportive but not yet decisive roles. These findings highlight the need to integrate social and energy policies to raise household incomes, improve access to renewable technologies, and promote energy efficiency measures. The developed model offers a tool for enhancing state policies to alleviate energy poverty under wartime constraints and in post-war recovery.

Open Access: Yes

DOI: 10.21511/ee.16(4).2025.06

Comparison of feed-forward control strategies for simplified vertical hopping model with intrinsic muscle properties

Ambrus Zelei Dóra Patkó

Publication Name: Bioinspiration and Biomimetics

Publication Date: 2024-11-01

Volume: 19

Issue: 6

Page Range: Unknown

Description:

To analyse walking, running or hopping motions, models with high degrees of freedom are usually used. However simple reductionist models are advantageous within certain limits. In a simple manner, the hopping motion is generally modelled by a spring-mass system, resulting in piecewise smooth dynamics with marginally stable periodic solutions. For a more realistic behaviour, the spring is replaced by a variety of muscle models due to which asymptotically stable periodic motions may occur. The intrinsic properties of the muscle model, i.e. preflexes, are usually taken into account in three complexities—constant, linear and Hill-type. In this paper, we propose a semi-closed form feed-forward control which represents the muscle activation and results in symmetrical hopping motion. The research question is whether hopping motions with symmetric force-time history have advantages over asymmetric ones in two aspects. The first aspect is its applicability for describing human motion. The second aspect is related to robotics where the efficiency is expressed in term of performance measures. The symmetric systems are compared with each other and with those from the literature using performance measures such as hopping height, energetic efficiency, stability of the periodic orbit, and dynamical robustness estimated by the local integrity measure (LIM). The paper also demonstrates that the DynIn MatLab Toolbox that has been developed for the estimation of the LIM of equilibrium points is applicable for periodic orbits.

Open Access: Yes

DOI: 10.1088/1748-3190/ad7345

Analyzing the impact of geographical diversification on portfolio performance

Gergő Thalmeiner László Pataki Attila Bányai Tatay Tibor

Publication Name: Teruleti Statisztika

Publication Date: 2025-01-01

Volume: 15

Issue: 2

Page Range: 321-340

Description:

The portfolio theory, which originated in the 1950s, pointed out that portfolio diversification allows investors to reduce risk. However, in addition to sector diversification, geographical diversification has been considerably less emphasized in equity investment evaluation. Our study contributes to this area. The calculations were conducted over two periods: 2008–2013 and 2014–2019. We constructed our portfolio using only exchange-traded funds (ETFs). We created two portfolios: one geographically diversified and the other focused exclusively on European markets. The geographically diversified portfolio comprised the IEV (iShares Europe ETF), EWH (iShares MSCI Hong Kong ETF), and EWZ (iShares MSCI Brazil ETF) portfolios. For our analysis, we used an approach based on the Monte Carlo simulation. The simulation calculated the Sharpe ratio of the portfolios, annualizing the metrics using the 252 trading day approach. We performed 10,000 iterations to ensure the robustness and reliability of our model. In the first period (2008–2013), we found that the geographically diversified portfolio showed higher volatility and generally lower risk-adjusted returns than the non-geographically diversified portfolio focused on Europe. Conversely, in the second period (2014–2019), the geographically diversified portfolio outperformed the non-geographically diversified portfolio in terms of risk-adjusted returns, suggesting that geographic diversification is preferable in certain market environments, particularly during periods of economic growth. In conclusion, investors should explore the potential of geographic diversification.

Open Access: Yes

DOI: 10.15196/RS150206

Performance prediction of conservative parallel discrete event simulation

Andras Varga Gábor Lencse

Publication Name: 8th International Industrial Simulation Conference 2010 Isc 2010

Publication Date: 2010-01-01

Volume: Unknown

Issue: Unknown

Page Range: 214-219

Description:

In a previous paper, a quantitative criterion has been proposed for efficient execution of the Null Message Protocol, the best-known conservative parallel discrete event simulation (PDES) protocol. The criterion is based on a novel concept of the coupling factor, and allows one to use intuitive and easy-to-measure input parameters. The criterion can be used to assess simulation models' potential for parallel execution as well as the maximum partitioning that may still potentially yield good performance. This paper deals with experimental verification of the proposed rule that a large coupling factor is a necessary precondition for getting a good speed-up with conservative parallel simulation. A closed queueing network is used as simulation model, and it is run on up to 24 CPU cores. It is shown that the criterion provides a quick and convenient way to determine whether a simulation model has a potential for speed-up before actually investing work in the parallelization.

Open Access: Yes

DOI: DOI not available

Extension of isothermal time-temperature parameters to non-isothermal conditions: Application to the simulation of rapid tempering

Janez Grum Gustavo Sanchez Sarmiento Augusto Moita De Deus Imre Felde Tamás Réti Rafael Colas

Publication Name: Strojniski Vestnik Journal of Mechanical Engineering

Publication Date: 2010-04-28

Volume: 56

Issue: 2

Page Range: 84-92

Description:

A phenomenological method for constructing non-isothermal, generalized time-temperature parameters (GTT parameters) is presented. An analysis of the relationship between the various traditional isothermal time-temperature parameters has verified that the generalized Dorn-parameter is regarded to be the sole non-isothermal complex parameter to which a rigorous, physically well-founded interpretation is attributed. Possible applications of GTT parameters are illustrated by examples concerning the prediction of hardness change in quenched steels during rapid tempering treatments. © 2010 Journal of Mechanical Engineering. All rights reserved.

Open Access: Yes

DOI: DOI not available

Taxonomic contribution to knowledge of the oribatid mite genus Achipteria (Acari, Oribatida, Achipteriidae)

Sergey G. Ermilov Jenő Kontschán

Publication Name: International Journal of Acarology

Publication Date: 2025-01-01

Volume: 51

Issue: 2

Page Range: 81-87

Description:

The oribatid mite family Achipteriidae is recorded in the Dominican Republic for the first time. A new species of the genus Achipteria—A. (Izuachipteria) dominicanensissp. nov.—is described, based on adults collected from leaf litter in a mixed forest. The species is characterized by the morphology of the lamella (triangular distally, without strong lateral tooth), the location of the lamellar seta (on ventral side of the lamella), the length of the bothridial seta (long), the ornamentation and morphology of the pteromorph (partially striate, with lateral tooth), the number of the leg claws (one), and the absence of the notogastral saccules. The taxonomic status of the subgenera Achipteria (Cubachipteria), A. (Hokkachipteria), and A. (Izuachipteria) is discussed. An identification key, distribution, and habitat of the known representatives of Achipteria (Izuachipteria) are presented.

Open Access: Yes

DOI: 10.1080/01647954.2024.2439799

Digital business ecosystem tools as interoperability drivers

Maria Raffai Miklós Herdon Ádám Péntek Tünde Rózsa

Publication Name: IFIP Advances in Information and Communication Technology

Publication Date: 2010-01-01

Volume: 326

Issue: Unknown

Page Range: 116-127

Description:

Today’s businesses form a highly interconnected network of companies, organisations, technologies, consumers, products and services. The concept of the Digital Business Ecosystem (DBE) has been come life in order to build an Internet-based environment in which businesses will be able to interact with each other more efficiently. In a Digital Ecosystem, a leadership structure is formed in order to be capable of responding to the dynamic needs of the environment. The agent in a Digital Ecosystem can both be a client and a server at the same time. With the same message, agents can simultaneously offer a service to others as a Server and request help as a Client. Industries may have their own systems but they are not yet business ecosystems. Digital ecosystems rely on a technological infrastructure to mediate the formalisation of knowledge in SME networks, the creation of software services, and different type of interactions between SMEs. There are many fields of application in the agro-food industry where interoperability of information system would be essential. Amongst others food tracking and tracing, logistics, SRM and CRM integration all need interoperability solution in a heterogeneous environment. Our prototypes can help in building these cooperative information systems.

Open Access: Yes

DOI: 10.1007/978-3-642-15509-3_11

Implications of Financial Literacy on Pawnshop Usage

Omar A. Guirette- Barbosa Selene Castañeda- Burciaga Csongor Czipf Absalón J. Salmerón- Zapata José G. Vargas- Hernandez

Publication Name: Policy Implications on International Financial Economics and Banking

Publication Date: 2025-01-01

Volume: Unknown

Issue: Unknown

Page Range: 441-464

Description:

This chapter aims to analyze financial literacy implications on pawnshop usage. The analysis departs from the assumption that individuals and micro-organizations lacking financial literacy and lower opportunities to have access to short-term credit provided by formal financing and banking institutions, are more likely to use pawnshops to get easily and fastest financial resources urgently needed for survival, living expenses and other required matters. The method used is the semi-structured interviews to borrowers followed by meta-analysis and meta-cognitive approaches based on conceptual, theoretical and empirical literature review. The chapter concludes that the financial literacy of undeserved individuals and micro-organizations, tend to reduce their access to formal financial and banking institutions to get credit, driving them to use pawnshops.

Open Access: Yes

DOI: 10.4018/979-8-3373-3725-8.ch015

Vehicle Model for Driving Strategy Optimization of Energy Efficient Lightweight Vehicle

Péter Korös Zoltan Pusztai Ferenc Friedler

Publication Name: Chemical Engineering Transactions

Publication Date: 2021-01-01

Volume: 88

Issue: Unknown

Page Range: 385-390

Description:

The energy consumption and CO2 emission of urban vehicles are highly dependent on their operation. Vehicle models can be used for optimizing driving strategy for emission reduction. This paper proposes a novel vehicle model of a one-seat electric vehicle dedicated for Shell Eco-marathon (SEM), the most famous and largest race of energy efficient vehicles. The available vehicle dynamical formulas cannot be directly used to describe the characteristics of lightweight vehicles. In the current work, a novel grey-box vehicle model has been introduced, based on measurement scenarios. The whole model has been elaborated in MATLAB Simulink environment, where individual subassemblies were defined for driving resistance model, powertrain model, and the racetrack characteristics. The resistance force model manages the forces in straight line moving and also takes the effect of cornering into account. Based on test bench measurements the complete efficiency map of the drivetrain was created and implemented into the vehicle model. The presented vehicle model is suitable for driving strategy optimization. By optimizing this model, 7.1 % energy savings have been achieved compared to best human driven lap. Driving strategy optimization will be essential, especially for autonomous vehicles, expressing the importance of the presented results in the future.

Open Access: Yes

DOI: 10.3303/CET2188064