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Found 6407 publications

The Personal Assistant application, problem definition

Claudiu Radu Pozna Péter Földesi János Kovacs

Publication Name: 4th IEEE International Conference on Cognitive Infocommunications Coginfocom 2013 Proceedings

Publication Date: 2013-01-01

Volume: Unknown

Issue: Unknown

Page Range: 851-856

Description:

The subject of the paper is a personal assistant design. The goal of personal assistant is a daily activities list planning. The personal assistant will assist the costumer (human operator) for planning an optimum succession of desired activities. The solution is based on objective and subjective information. The paper focus on problem definition, mathematical structure of the concepts which are involved and a first solution analyze. © 2013 IEEE.

Open Access: Yes

DOI: 10.1109/CogInfoCom.2013.6719215

Several meshless solution techniques for the stokes flow equations

Csaba Gáspár

Publication Name: Computational Methods in Applied Sciences

Publication Date: 2009-01-01

Volume: 11

Issue: Unknown

Page Range: 141-158

Description:

The permanent 2D Stokes flow is considered. The applied solution technique is the classical pressure correction method, which converts the original problem to a sequence of Poisson equations. These Poisson equations are discretized and solved in a meshless way, using local interpolation based on radial basis functions. Further improvement can be achieved by using a direct multi-elliptic approach instead of local interpolation, which results in re-globalized, quadtree-based schemes. The number of unknowns can be reduced by applying the method of fundamental solutions. A special regularization technique is introduced which uses higher order fundamental solutions without singularities. This regularization is combined with the direct multi-elliptic interpolation, which significantly reduces the computational cost and makes it possible to avoid the use of dense and ill-conditioned matrices.

Open Access: Yes

DOI: 10.1007/978-1-4020-8821-6_9

Gaussian-Process-Based Adaptive Tracking Control With Dynamic Active Learning for Autonomous Ground Vehicles

R. Toth Tamas Peni Kristóf Floch

Publication Name: IEEE Transactions on Control Systems Technology

Publication Date: 2026-01-01

Volume: 34

Issue: 2

Page Range: 800-812

Description:

This article proposes an active-learning-based adaptive trajectory tracking control method for autonomous ground vehicles to compensate for modeling errors and unmodeled dynamics. The nominal vehicle model is decoupled into lateral and longitudinal subsystems, which are augmented with online Gaussian processes (GPs) using measurement data. The estimated mean functions of the GPs are used to construct a feedback compensator, which, together with a linear parameter-varying (LPV) state feedback controller designed for the nominal system, gives the adaptive control structure. To assist exploration of the dynamics, the article proposes a new, dynamic active learning method to collect the most informative samples to accelerate the training process. To analyze the performance of the overall learning tool-chain provided controller, a novel iterative, counterexample-based algorithm is proposed for calculating the induced L2 gain between the reference trajectory and the tracking error. The analysis can be executed for a set of possible realizations of the to-be-controlled system, giving a robust performance certificate of the learning method under variation of the vehicle dynamics. The efficiency of the proposed control approach is shown on a high-fidelity physics simulator and in real experiments using a 1/10 scale F1TENTH electric car.

Open Access: Yes

DOI: 10.1109/TCST.2025.3632358

Accuracy Assessment and Validation of Multi-Source CHIRPS Precipitation Estimates for Water Resource Management in the Barada Basin, Syria

Katalin Bene Xiaogang Shi Khaled Alghafli Firas Alsilibe Ghada Bilal

Publication Name: Remote Sensing

Publication Date: 2023-04-01

Volume: 15

Issue: 7

Page Range: Unknown

Description:

The lack of sufficient precipitation data has been a common problem for water resource planning in many arid and semi-arid regions with sparse and limited weather monitoring networks. Satellite-based precipitation products are often used in these regions to improve data availability. This research presents the first validation study in Syria for Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS) estimates using in-situ precipitation data. The validation was performed using accuracy and categorical statistics in the semi-arid Barada Basin, Syria, between 2000 and 2020. Multiple temporal scales (daily, pentad, monthly, seasonally, and annual) were utilized to investigate the accuracy of CHIRPS estimates. The CHIRPS results indicated advantages and disadvantages. The main promising result was achieved at the seasonal scale. Implementing CHIRPS for seasonal drought was proven to be suitable for the Barada Basin. Low bias (PBwinter = 2.1%, PBwet season = 12.7%), high correlation (rwet season = 0.79), and small error (ME = 4.25 mm/winter) support the implementation of CHIRPS in winter and wet seasons for seasonal drought monitoring. However, it was observed that CHIRPS exhibited poor performance (inland pentads) in reproducing precipitation amounts at finer temporal scales (pentad and daily). Underestimation of precipitation event amounts was evident in all accuracy statistics results, and the magnitude of error was higher with more intense events. CHIRPS results better corresponded in wet months than dry months. Additionally, the results showed that CHIRPS had poor detection skill in drylands; on average, only 20% of all in-situ precipitation events were correctly detected by CHIRPS with no effect of topography found on detection skill performance. This research could be valuable for decision-makers in dryland regions (as well as the Barada Basin) for water resource planning and drought early warning systems using CHIRPS.

Open Access: Yes

DOI: 10.3390/rs15071778

The effect of the perceived value of cultural services on the quality of life

Ida Ercsey László Józsa

Publication Name: International Review on Public and Nonprofit Marketing

Publication Date: 2016-04-01

Volume: 13

Issue: 1

Page Range: 15-36

Description:

In international and especially in Hungarian marketing literature, a few pieces of research deal with analysis of the relationship between the subjective quality of life and the services. The objective of this article is to explore, what the role of the perceived value of cultural activities play in the evaluation of the young people’ quality of life. First, we look over the quality of life studies in the cultural industry. Next, we study the perceived value comparing two main approaches to the conceptualisation of this framework. Based on the scales of previous studies and our results of the exploratory phase (small-group interviews, and pilot study) we developed the initial scales for measurement of the subjective quality of life (QOL) and the perceived value of cultural activities. We conducted a survey to test our hypotheses. The target population of our research is consumers who participated in cultural activities between 14 and 30 ages in one Hungarian region. Our results show that perceived value of cultural services has three different dimensions: functional (quality and price of cultural service, installation of cultural provider, and personnel expertise), emotional and social ones. We found that the functional dimension of cultural services has positive effect on the consumers’ global QOL. Besides, the emotional and social values of cultural services contribute to the higher perception of the family and friend relationships among young users. Finally, we discuss our results, managerial implications, and formulate limitations of our empirical research and further research.

Open Access: Yes

DOI: 10.1007/s12208-015-0140-9

A virtual audio environment for testing dummy-head HRTFs modeling real life situations

József Répás György Wersényi

Publication Name: Proceedings of Forum Acusticum

Publication Date: 2014-01-01

Volume: 2014-January

Issue: Unknown

Page Range: Unknown

Description:

Virtual audio simulators usually incorporate HRTF filtering and headphone playback. The most important parameters for simulation include accuracy and spatial resolution of the applied HRTFs, setting the individual parameters (customization) and further signals processing algorithms in order to equalize the headphone or tracking head movements. This paper presents a custom built MATLAB-based virtual audio environment for listening tests using various dummy-head HRTFs, ITD setting methods, headphone equalization etc. Furthermore, first results from a listening test for comparison of HRTFs recorded with a manikin wearing hair or glasses are also presented.

Open Access: Yes

DOI: DOI not available

Effect of Lateral Deviation on Braking Dynamics of Automotive Brake Discs

Gergő Sütheö

Publication Name: International Journal of Automotive Science and Technology

Publication Date: 2025-12-17

Volume: 9

Issue: 1st Future of Vehicles Conf.

Page Range: 101-109

Description:

The advancement of the automotive industry and its associated challenges necessitate the application of modern diagnostic methods for fault detection and the prevention of potential failures. The aim of this scientific publication is to investigate the braking behavior of brake discs subjected to varying degrees of lateral deviation, using noise, vibration, and harshness (NVH) diagnostic methods. The research aims to support the development and broader adop-tion of advanced, autonomous maintenance procedures. During the experimental program, a seventh-generation electric Volkswagen e-Golf brake disc was tested under both laboratory and real-world proving ground conditions. The results of the analysis show that as the brake disc run-out increased, lateral acceleration values intensified (pulsation was observed); these vibra-tions were clearly perceptible through the steering wheel during testing. Based on the acquired data, the differences in braking dynamics were analysed. Using the applied NVH method, along with the selected measurement points, provided a reliable diagnostic procedure. The findings support preventive maintenance and improved design reliability. Quantitatively, increasing disc run-out from 0.02 mm (OEM) to 0.12 mm (defective aftermarket) raised lateral acceleration peaks at the wheel carrier from within ±1 g to nearly ±3 g and lengthened the average braking distance from 39 m to 41.5 m at 100 km/h (n=3 per disc). These findings indicate a measurable safety impact under otherwise identical conditions.

Open Access: Yes

DOI: 10.30939/ijastech..1838956

Enabling in-depth analysis in heat exchanger network synthesis via graph-theoretic tool: Experiences in Swinburne University of Technology Sarawak Campus

Ákos Orosz Jaka Sunarso Bing Shen How Sin Yong Teng Ferenc Friedler

Publication Name: Education for Chemical Engineers

Publication Date: 2023-04-01

Volume: 43

Issue: Unknown

Page Range: 100-112

Description:

The ability and capability to analyze and benchmark alternative designs on top of the optimal network are deemed valuable competencies for current and future chemical engineers. In this context, a process graph (P-graph)-inspired tool – P-HENS is introduced to an integrated plant design unit in an undergraduate chemical engineering degree program at Swinburne University of Technology Sarawak Campus in Malaysia. The energy recovery aspect is one of the key design elements in the integrated plant design unit. The introduction of P-HENS, which is capable of mathematically determining multiple optimal and sub-optimal solutions is considered useful for the students to (i) identify plausible heat exchanger networks (HENs) structures that may be overlooked using conventional approaches and (ii) enable a more in-depth analysis to justify the selected design. Overall, the implementation of P-HENS shows positive outcomes, where this free-of-charge software complements the learning of conventional manual approaches used in HENs synthesis. Furthermore, recommendations suggested by the users (students) are collected and compiled for potential future software development. This work serves as an essential reference for other chemical engineering educators who are teaching pinch analysis or heat integration-related courses.

Open Access: Yes

DOI: 10.1016/j.ece.2022.12.003

Reinventing government and the separation of powers

István Stumpf

Publication Name: Hungarian Journal of Legal Studies

Publication Date: 2016-03-01

Volume: 57

Issue: 1

Page Range: 42-58

Description:

Challenges caused by the global economic crisis in connection with the structural, political changes transformed the construction, the nature, and the operation of the executive branch. During the last decades in the separation of powers' system the state had been rediscovered and governmental power had been appreciated. In a world covered with the internet, financial, economic and political crisis situations appeared; governments and governmental centres had to give sufficient answers to global challenges. The world under the pressure of the media changed the daily routine of the governmental work: beside the good decision-making, carrying the governments' point across parliaments and public opinion too became increasingly significant. Strengthening the symbiosis between the legislative and executive branch in parliamentary governmental systems can be observed. Members of the governing party attending the rigorous party discipline are decreasingly able to function as democratic control. These members rather become patronisers ('voting machines') of the governmental intention without critical voices. The personality of the politicians coming to the front and the marketability of the politics in the media also strengthened the process which resulted in the intensity of the Prime Minister's role within the executive branch. Increasing the role of the Prime Minister and governmental central bodies lead to the weakening of the government's corporative character, and the government's gaining ground opposed to the Parliament. According to international examples in significant western European parliamentary democracies (for example: United Kingdom: Margaret Thatcher and Tony Blair, Italy: Silvio Berlusconi, Sweden: Göran Persson) the role of the Prime Minister (as the head of the government) also appreciably strengthened. Beside this attitude, the outsourcing of each governmental function (good governance), the sufficiency of state's strengthening (good government), and making governmental public services available electronically (e-government) are also under hard discussion. The aim of this paper is to review - based on new constitutional and other changes of public law - the centralization of the head of the Hungarian government; the strengthening of the 'chancellor-principle' by the Hungarian Fundamental Law; and the process that lead to the Prime Minister's Office becoming 'top chancery'. The paper takes into consideration the transformation of the separation of powers' system and the strengthening of the Prime Minister's role within the executive branch and its affect on the Hungarian administrative system.

Open Access: Yes

DOI: 10.1556/2052.2016.57.1.4