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Publications - 6374

Policy priorities for improving Global Innovation Index score and innovative performance in upper-middle-income countries: Implications for Armenia

Gayane Tovmasyan Svitlana Bilan Hamlet Mkrtchyan Anna Makaryan Svetlana Dallakyan Verej Isanians Harutyun Sargsyan

Publication Name: Problems and Perspectives in Management

Publication Date: 2025-01-01

Volume: 23

Issue: 1

Page Range: 569-583

Description:

As an upper-middle-income country, Armenia should develop and implement targeted policies, such as increased R&D investments, education reforms, and industry-academia collaboration, to enhance its innovation performance. Strengthening these areas is expected to contribute to higher Global Innovation Index (GII) rankings, reflecting improved national innovation capacity. This study aims to estimate the impact of various GII components (including pillars, sub-indices, and sub-pillars) on the overall GII and pillar scores for upper-middle-income countries. Based on these findings, the study seeks to identify Armenia’s key policy priorities and provide targeted recommendations for enhancing its innovation performance. This study employs a cross-sectional regression to analyze the factors influencing GII scores in upper-middle-income countries, assessing the impact of sub-indices, pillars, and sub-pillars. The analysis reveals that market sophistication and creative outputs strongly influence GII scores among upper-middle-income countries, contributing significantly to national innovation performance. Additionally, knowledge and technology outputs, human capital and research, and infrastructure pillars show a statistically significant impact at the 5% level. Notably, even minor improvements in innovation output sub-index scores account for substantial variations in GII rankings. These findings suggest that Armenia should prioritize targeted education reforms, increase R&D investment, and strengthen university-industry linkages to enhance its innovation ecosystem and improve its global competitiveness.

Open Access: Yes

DOI: 10.21511/ppm.23(1).2025.43

Model Order Reduction Methods for Rotating Electrical Machines: A Review

Tamas Orosz Kristóf Levente Kiss

Publication Name: Energies

Publication Date: 2024-10-01

Volume: 17

Issue: 20

Page Range: Unknown

Description:

Due to the rise of e-mobility applications, there is an increased demand to create more accurate control methods, which can reduce the loss in an e-drive system. The accurate modeling of the rotating machines needs to resolve a partial differential equation system that describes the thermal and mechanical behavior of the different parts in addition to the electromagnetic design. Due to these models’ limited resources and high computation demand, they cannot be used directly for real-time control. Model order reduction methods have been of growing interest in the past decades and offer solutions for this problem. According to the processed literature, many model order reduction-based methods are used for a wide range of problems. However, a paper has not been published that discusses a model order reduction-based real-time control model that is actually used in the industry. This paper aims to summarize and systematically review the model order reduction methods developed for rotating electrical machines in the last two decades and examine the possible usage of these methods for a real-time control problem.

Open Access: Yes

DOI: 10.3390/en17205145

Effects of local ground conditions on site response analysis results in Hungary

O. Kegyes-Brassai Zsolt Szilvágyi Ákos Wolf R. P. Ray

Publication Name: Icsmge 2017 19th International Conference on Soil Mechanics and Geotechnical Engineering

Publication Date: 2017-01-01

Volume: 2017-September

Issue: Unknown

Page Range: 2003-2006

Description:

Ground conditions play an important role for both seismic hazard assessment and structural design for seismic actions. Generally, 1D site response analysis is the first step toward evaluating local conditions. Often the process is simplified by applying a single reference peak ground acceleration general response spectrum based on soil category. Seismic waves are amplified selectively by near-surface soil deposits that possess strain dependent stiffness and damping parameters that vary with each layer as well as with depth. In order to take these local ground conditions into account, field investigations were carried out for this study. Seismic CPT and MASW measurements were used for determining in situ small strain stiffness profiles at different locations in Hungary. Results of the investigations were used as input data for ground response analyses. Results are presented to show benefits of the detailed investigations as compared to simplified analysis methods based on estimated soil parameters and to EC-8 design spectra.

Open Access: Yes

DOI: DOI not available

Helianthus tuberosus at home and away: Stronger ecological impacts in invaded than in native range are not explained by arbuscular mycorrhizal colonization

Robert W. Pal Rita Filep Bradley J. Cook David U. Nagy K. Nagy A. Lengyel Ádám Imri Klára Czakó-Vér Ágnes Farkas

Publication Name: Preslia

Publication Date: 2021-01-01

Volume: 93

Issue: 4

Page Range: 363-376

Description:

The impact of invasive plants on vegetation can vary greatly depending on the characteristics of the invaders and community invasibility. As to the factors that influence a plant's ability to invade, recent studies suggest that arbuscular mycorrhizal fungi (AMF) may be important regulators in plant invasions. To better understand the interactions of Helianthus tuberosus with co-occurring species in its native NorthAmerican and invaded European ranges,we carried out plot-based field surveys to determine whether the cover of H. tuberosus, its stem number and height, bare ground cover and amount of litter differ between ranges and how they interact with numbers of species in the plant community. To provide information aboutAMFcolonization of H. tuberosus,we evaluatedAMFcolonization in both ranges and tested the difference between continents, the effect of cover of H. tuberosus and their interaction with AMF. In the invaded range in Europe, H. tuberosus plants grew taller, had a greater stem density and there were fewer species in the invaded plant communities than in its native range in North America. In contrast, the cover of H. tuberosus and litter cover did not differ between the two continents. Plants of H. tuberosus were colonized by AMF in both ranges, but we found no statistical support for the potential effects of continent, the cover of H. tuberosus and their interaction with AMF. Overall, our study revealed that H. tuberosus exerts a negative impact on co-occurring species in the invaded European range, but not in North America where the species is native. To our knowledge, this is the first evaluation of AMF colonization of H. tuberosus at home and away and the results do not support either the degraded or enhanced mutualism hypotheses.

Open Access: Yes

DOI: 10.23855/preslia.2021.363

Drop performance of dangerous goods packages in the aspect of parcel delivery standards

No authors available

Publication Name: 21st IAPRI World Conference on Packaging 2018 - Packaging: Driving a Sustainable Future

Publication Date: 2019-01-01

Volume:

Issue:

Page Range: 569-577

Description:

Requirements for dangerous goods packaging are well known, whatever version are used. The testing circumstances are strictly defined for each transportation method (road, rail, air, sea). But nowadays it is becoming a practice that courier express operators transport dangerous goods as single package. This parcel delivery method means a higher risk for all kind of logistics participants. By this service the packages are delivered fast, but handled more roughly than in comparison to LTL (less than truckload) or FTL (full truck load). Naturally, the parcel delivery sector uses its own suitability testing methods, which are also well defined. These procedures are coming from various standards such as ASTM, ISTA or corporate (FedEx) standards. This paper compares the most common parcel delivery testing conditions concerning the drop test requirements of DGR (Dangerous Goods Regulation) using packaging such as paper bag, corrugated fibreboard box, steel drum and plastic jerrycan, respectively. Then the test results were analyzed to present the differences.

Open Access: No

DOI: DOI not available

Stability analysis and performance comparison of three 6to4 relay implementations

Sándor Répás Viktor Horváth Gábor Lencse

Publication Name: 2015 38th International Conference on Telecommunications and Signal Processing Tsp 2015

Publication Date: 2015-10-09

Volume: Unknown

Issue: Unknown

Page Range: 82-87

Description:

During the IPv6 deployment there is a frequently occurring situation where two IPv6 enabled hosts need to communicate with each other over a network that supports only IPv4. Application of the 6to4 IPv6 transition method can solve this problem. The performance and stability of the different 6to4 relay implementations is a very important subject. We measured the performance and tested the stability of three open source 6to4 relay implementations under Debian Linux, OpenBSD and OpenWRT platforms. We present and discuss our results, analyze the stability of the 6to4 relay implementations and compare their performance metrics. Our measurements methods may be useful for other researchers, and our results may help the system architects to choose the appropriate solution.

Open Access: Yes

DOI: 10.1109/TSP.2015.7296228

Tribological Investigation of the Effect of Nanosized Transition Metal Oxides on a Base Oil Containing Overbased Calcium Sulfonate

D. Tóth I. Szabó Hajnalka Hargitai

Publication Name: Lubricants

Publication Date: 2023-08-01

Volume: 11

Issue: 8

Page Range: Unknown

Description:

In this study, copper(II) oxide, titanium dioxide and yttrium(III) oxide nanoparticles were added to Group III-type base oil formulated with overbased calcium sulfonate. The nanosized oxides were treated with ethyl oleate surface modification. The tribological properties of the homogenized oil samples were tested on a linear oscillating tribometer. Friction was continuously monitored during the tribological tests. A surface analysis was performed on the worn samples: the amount of wear was determined using a digital optical and confocal microscope. The type of wear was examined with a scanning electron microscope, while the additives adhered to the surface were examined with energy-dispersive X-ray spectroscopy. From the results of the measurements, it can be concluded that the surface-modified nanoparticles worked well with the overbased calcium sulfonate and significantly reduced both wear and friction. In the present tribology system, the optimal concentration of all three oxide ceramic nanoadditives is 0.4 wt%. By using oxide nanoparticles, friction can be reduced by up to 15% and the wear volume by up to 77%. Overbased calcium sulfonate and oxide ceramic nanoparticles together form a lower friction anti-wear boundary layer on the worn surfaces. The results of the tests represent another step toward the applicability of these nanoparticles in commercial engine lubricants. It is advisable to further investigate the possibility of formulating nanoparticles into the oil.

Open Access: Yes

DOI: 10.3390/lubricants11080337

Blockchain as a driver for smart city development: Application fields and a comprehensive research agenda

Andreas Strebinger Horst Treiblmaier Abderahman Rejeb

Publication Name: Smart Cities

Publication Date: 2020-09-01

Volume: 3

Issue: 3

Page Range: 853-872

Description:

The term “Smart City” denotes a comprehensive concept to alleviate pending problems of modern urban areas which have developed into an important work field for practitioners and scholars alike. However, the question remains as to how cities can become “smart”. The application of information technology is generally considered a key driver in the “smartization” of cities. Detailed frameworks and procedures are therefore needed to guide, operationalize, and measure the implementation process as well as the impact of the respective technologies. In this paper, we discuss blockchain technology, a novel driver of technological transformation that comprises a multitude of underlying technologies and protocols, and its potential impact on smart cities. We specifically address the question of how blockchain technology may benefit the development of urban areas. Based on a comprehensive literature review, we present a framework and research propositions. We identify nine application fields of blockchain technology in the smartization of cities: (1) healthcare, (2) logistics and supply chains, (3) mobility, (4) energy, (5) administration and services, (6) e-voting, (7) factory, (8) home and (9) education. We discuss current developments in these fields, illustrate how they are affected by blockchain technology and derive propositions to guide future research endeavors.

Open Access: Yes

DOI: 10.3390/smartcities3030044

Preface

No authors available

Publication Name: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Publication Date: 2019-01-01

Volume: 11291 LNAI

Issue:

Page Range: V

Description:

Open Access: No

DOI: DOI not available