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Analyzing employee behavior related questionnaires by combined fuzzy signature model

Dalia Susniene Daiva Žostautienė Ojaras Purvinis László T. Kóczy

Publication Name: Fuzzy Sets and Systems

Publication Date: 2020-09-15

Volume: 395

Issue: Unknown

Page Range: 254-272

Description:

The evaluation of data obtained from responses given to questionnaires in humanities and social sciences, such as management, linguistics, etc. is a complex task with the necessity of dealing with the inherent subjectivity and vagueness in such data. In this paper, a method based on fuzzy signatures (FSigs), suitable for analyzing questionnaires with hierarchically connected (partially) vague responses is proposed, and its applicability will be demonstrated by a real life problem; the partial analysis of an ongoing research examining employee behavior in various companies. The linkage of the factors hidden in the data bases obtained from the answers to the questionnaires, containing various factors interconnected in a more or less tight way, are represented by a hierarchical FSig system, allowing further evaluation and the discovery of emerging connections and deeper patterns among the responses, thus extending the idea of the original FSig model towards a more general, fuzzy-fuzzy signature approach. The method proposed here is a combination of some statistical elements with the Fuzzy Signature model, and it also uses Kohonen-maps in order to discover deeper structural components in the data pool. As FSigs are suitable to express hierarchically structured connections among vague and imprecise features of the individual data, the statistical analysis helps reveal the degrees of redundancies and the closeness of connectedness of the individual elements within the responses, and thus enable the construction of a relevant FSig tree graph for the data on hand, while further expert domain knowledge helps with determining the proper fuzzy aggregations in the intermediate nodes of the FSigs. The case study presented is based on data obtained from North Lithuanian companies. The results of the case study focusing on the analysis of the connection between OCB and CWB, and other factors, disclose some interesting and, partly unexpected, results. They indicate a strong and unambiguous relationship between career satisfaction and OCB, which is not very surprising. However, it is found that there is no relationship with gender, age, and actual position in the company, which are generally supposed to be determining factors. These results may be further validated by expert knowledge, and thus the new combined method for evaluating structured multicomponent data and internal dependencies is adequate.

Open Access: Yes

DOI: 10.1016/j.fss.2020.04.018

Residual stresses in carburised, carbonitrided and case-hardened components (Part 2)

Tamás Réti

Publication Name: Heat Treatment of Metals

Publication Date: 2004-03-11

Volume: 31

Issue: 1

Page Range: 4-10

Description:

An overview is given of the significant progress in research focused on the assessment of residual stress effects in case-hardened components. Focus is on relevant computational models intended to simulate stress evolution during heat treatment.

Open Access: Yes

DOI: DOI not available

Modelling of virtualized servers

Akos Kovacs 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: 421-425

Description:

The virtualized systems are one of the key elements of the next generation IT infrastructures. Modeling it will prevent mistakes, and oversized management. Opennebula is one of the most current open source cloud management solutions. Together with Haizea, they are a powerful tool to model and manage a virtualized infrastructure trough the API of Openebula. Haizea has multiple scheduler algorithms that are more effective than that of Opennebula. We performed several experiments to compare simulation and measurement capabilities of Haizea and we highlighted some difference between them which can be reduced if required.

Open Access: Yes

DOI: 10.1109/TSP.2015.7296296

Risk Management for Cold Supply Chain: Case of a Developing Country

Laszlo Vasa Dragan Pamucar Yousaf Ali Amin Ullah Khan

Publication Name: Acta Polytechnica Hungarica

Publication Date: 2022-01-01

Volume: 19

Issue: 8

Page Range: 161-185

Description:

Cold Supply Chain (CSC) involves temperature-controlled activities in the overall process, ranging from the raw material storage to the final supply of the products to the consumers. The activities involved are easily exposed to risks such as temperature and humidity, equipment failure and quality risk to name a few. Such sensitive processes need proper risk mitigation strategies, to ensure the effective functioning of the overall CSC. For this purpose, the current research conducted a vigorous literature review and identified 40 relevant risks related to CSC in a developing country. The risks were analyzed using Failure Mode and Effect Analysis (FMEA)-Risk Priority Number (RPN) technique to shortlist the significant risks. The significant risks were then subjected to the Full Consistency Method (FUCOM) for prioritization. The results concluded, contamination of food, temperature and humidity and quality as the top-three risks that can be dangerous for the overall cold supply chain. To overcome these risks, the study recommends the proper implementation of traceability systems and Radio Frequency Identification (RFID) systems. Furthermore, employing the latest technologies and efficient personnel training can also help overcome these risks. Such an application of the study in the case of a developing country, Pakistan's CSC forms to be the first of its kind. Furthermore, the application of FMEA-RPN along with the FUCOM technique in the scenario of CSC risk management forms the novelty of this research study.

Open Access: Yes

DOI: DOI not available

Randomized, double-blind, placebo-controlled, proof-of-concept study of the cortical spreading depression inhibiting agent tonabersat in migraine prophylaxis

M. D. Ferrari P. J. Goadsby J. G. Mills Attila Csanyi J. Olesen

Publication Name: Cephalalgia

Publication Date: 2009-07-01

Volume: 29

Issue: 7

Page Range: 742-750

Description:

Tonabersat is a novel putative migraine prophylactic agent with an unique stereospecific binding site in the brain. Tonabersat has been shown, in animal models, to inhibit experimentally induced cortical spreading depression, the likely underlying mechanism for migraine aura, and cerebrovascular responses to trigeminal nerve stimulation. The aim was to study the potential for tonabersat as a migraine preventive. A randomized, double-blind, placebo-controlled, multicentre, parallel group study recruited patients with migraine with and without aura experiencing between two and six migraine attacks per month. After a 1-month baseline they received tonabersat 20 mg daily for 2 weeks and 40 mg daily for a further 10 weeks. The primary end-point was the change in mean number of migraine headache days between the third month and the baseline period in the intention-to-treat population comparing the placebo (n = 65) and tonabersat (n = 58) groups. At the primary end-point there was a 1.0-day (95% confidence interval -0.33, 2.39; P = 0.14) difference in reduction in migraine days between tonabersat and placebo. There were 10 secondary efficacy end-points, of which two were statistically significant. In month 3 of treatment, the responder rate, defined as a 50% reduction in migraine attacks, was 62% for tonabersat and 45% for placebo (P < 0.05), and the rescue medication use was reduced in the tonabersat group compared with placebo by 1.8 days (P = 0.02). Placebo responses were particularly high for all end-points. At least one treatment-emergent adverse event was reported in the tonabersat group in 61% of patients compared with 51% in the placebo group; none was worrisome. Placebo responses were unexpectedly high in this trial, complicating straightforward interpretation of the study results. The good tolerability and promising efficacy results support further exploration of higher doses of tonabersat in larger controlled trials. © Blackwell Publishing Ltd.

Open Access: Yes

DOI: 10.1111/j.1468-2982.2008.01804.x

The Role of food aid and livelihood interventions in mediating the relationship between household’s resilience and economic empowerment

Laszlo Vasa Nassar Samia Zsuzsanna Naárné Tóth

Publication Name: Economic Annals Xxi

Publication Date: 2021-12-27

Volume: 194

Issue: 11-12

Page Range: 151-163

Description:

Theconceptofresiliencehasbeenutilizedtoexaminemorecomplexecologicalandsocioeconomic systems such as agri-food systems in developing countries. Gaza has one of the high unemployment rates globally, therefore keeping people imprisoned in poverty and dependent on external support to existing. The strategy for poverty reduction in Gaza primarily consists of giving food aid or multi-purpose cash-based assistance and livelihood projects; nevertheless, this does not reduce unemployment or poverty in the long term. Non-Governmental Organizations (NGOs) have increased their efforts to provide more effective and comprehensive interventions to the affected populations, especially in the Gaza Strip. The research implemented a quantitative methodology distributed to over 300 household benefited from food aid and livelihood interventions through the NGOs in Gaza Strip. The questionnaire had been constructed based on the Likert Scale ranging from 1 (Strongly Agree) to 5 (Strongly Disagree). The data had been treated using SPSS statistical tool and AMOS for structural equation modeling and analysis to study the mediating effect of food aid and livelihood interventions on the relationship between household resilience and economic empowerment in the Gaza Strip. The research found that the resilience ability of many families in the Gaza Strip has increased because of the humanitarian assistance provided by NGOs, which lead to reducing poverty and household resilience plays a vital role in minimizing poverty and alleviating suffering through empowering and engaging them in the economy. The research also found that food aid tends to critically impact the relationship between household resilience and economic empowerment. NGOs play an essential role in engaging the poor in the economy through providing food security and encouraging new investments and efforts to improve help effectiveness via greater coordination among players involved in the implementation and better planning, targeting, and providing aid to people in Gaza Strip. The research findings also showed that livelihood interventions mediate the relationship between household resilience and economic empowerment in Gaza Strip. The structural model supports that the livelihood interventions modulated the association between household resilience and economic empowerment.

Open Access: Yes

DOI: 10.21003/ea-v194-19

Hierarchical Diagnostics and Risk Assessment for Energy Supply in Military Vehicles

Peter Foldesi Szabolcs Kocsis Szurke Dániel Csikor Ferenc Szauter László T. Kóczy

Publication Name: Energies

Publication Date: 2022-07-01

Volume: 15

Issue: 13

Page Range: Unknown

Description:

Hybrid vehicles are gaining increasing global prominence, especially in the military, where unexpected breakdowns or even power deficits are not only associated with greater expense but can also cost the lives of military personnel. In some cases, it is extremely important that all battery cells and modules deliver the specified amount of capacity. Therefore, it is recommended to introduce a new measurement line of rapid diagnostics before deployment, in addition to the usual procedures. Using the results of rapid testing, we recommend the introduction of a hierarchical three-step diagnostics and assessment procedure. In this procedure, the key factor is the building up of a hierarchical tree-structured fuzzy signature that expresses the partial interdependence or redundancy of the uncertain descriptors obtained from the rapid tests. The fuzzy signature structure has two main important components: the tree structure itself, and the aggregations assigned to the internal nodes. The fuzzy signatures that are thus determined synthesize the results from the regular maintenance data, as well as the effects of the previous operating conditions and the actual state of the battery under examination; a signature that is established this way can be evaluated by “executing the instructions” coded into the aggregations. Based on the single fuzzy membership degree calculated for the root of the signature, an overall decision can be made concerning the general condition of the batteries.

Open Access: Yes

DOI: 10.3390/en15134791

Investigation of the effect of formwork shape on packing density of aggregates

Kitti Karolyfi Dániel Harrach Ferenc Papp

Publication Name: Pollack Periodica

Publication Date: 2020-12-31

Volume: 15

Issue: 3

Page Range: 125-134

Description:

Packing density of aggregate influences greatly the properties of concrete. Maximization of packing density increases the flowing ability and segregation resistance of the fresh concrete and the compressive strength of the hardened concrete. The determination of maximum density is difficult experimentally; therefore several models have been developed for that purpose. However, these models do not take the size of the formwork into account. In this study, 20 different formwork shapes were examined with defined aggregate fractions. Results show that increasing the formwork size increases the packing density of aggregate, and the growth depends on the formwork size and compaction method.

Open Access: Yes

DOI: 10.1556/606.2020.15.3.12

Technical Feasibility and Design Challenges of Unmanned Aerial Vehicle based Drive Testing on Cellular Networks

Oliver Takacs Istvan Drotar Tamas Kovacs György Wersényi

Publication Name: 2022 IEEE 1st International Conference on Internet of Digital Reality Iod 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: 23-32

Description:

Conventional drones are using ISM (Industrial, Scientific, and Medical) frequency bands during operation that can limit the range of the device. Limitations depend on the applied technologies in these frequency bands. With the help of cellular networks, BVLOS (Beyond Visual Line of Sight) UAV operations can be realized with increased safety. Unfortunately, base stations used in cellular networks target the lower, near-earth layers of air space. In case of drones, coverage in higher layers must be planned. Test procedures used in residential mobile network measurements record the quality parameters of the network measured on foot or by vehicle. Furthermore, the device carrying the measurement setup can cause serious interference with the measurement results. This paper presents current measurement methods and a concept for a solution to apply the measurement devices to an UAV. This new measurement method is correspondingly fit in the conception of IoD conference. We are executed the measurements by our own newly developed UAV system which can be a substitute solution of the walking measurements. Furthermore it provides opportunity to measurement some of that new layers of the air that have not had a chance before. Also, this innovation gives us the opportunity to perform measurements that have been difficult and dangerous so far, much easier and safer than before, without the need for human contact. In addition, measurements with drones have given a new perspective to the world of measurement methods.

Open Access: Yes

DOI: 10.1109/IoD55468.2022.9987208