Tomas Bata University in Zlín
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Finding suitable data mining techniques for software development effort estimation
No full textAn organization's new projects all go through an analysis process. The data gathered throughout the study serve as the cornerstone for important choices about complexity, resources, frameworks, timetables, costs, etc. Numerous methods have been developed throughout time to make the project analysis phase simpler, but most of them are still insufficient when it comes to the accuracy of the results. Without a precise analysis technique in place, even initiatives with clear goals might unravel in the later stages. Software project management still faces challenges in producing accurate and trustworthy estimates of software effort, particularly in the early stages of the software life cycle when the information available is more categorical than numerical. Predicting the number of person-hours, or months, required for software development is seen as a difficult task in Software Effort Estimation (SEE). Project cancellation or project failure is the outcome of overestimating or underestimating the software effort. Although useful sizing tools and methods derived from function points don't take into consideration the unique project management culture of a business. Data processing techniques are being investigated as a substitute estimation method as a result of these shortcomings in recent years. This research aims to propose a mixture method of functional sizing measurement and three data processing methods for effort estimation at the first stage of projects: Generalized Linear Models (GLM), Deep Learning Neural Networks (DLNN), and Decision Trees - Gradient Boosting Machine (GBM). These models’ estimation accuracies were contrasted so as to assess their potential value for implementation within businesses. Additionally, a combined strategy that mixes the output of the many algorithms is usually recommended so as to enhance prediction accuracy and forestall the incidence of over-fitting.Faculty of Applied Informatics, Tomas Bata University, (IGA/CebiaTech/2023/001); Julius Olufemi Ogunley
Reduction of histamine, putrescine and cadaverine by the bacteria Lacticaseibacillus casei depending on selected factors in the real condition of the dairy product
Get PDFOne way to effectively reduce the number of biogenic amines (BAs) in food is through enzymatic reduction using bacteria, such as lactic acid bacteria. This study focuses on the ability of the bacterial strain Lacticaseibacillus casei CCDM 198 to reduce the number of three important BAs (histamine, putrescine and cadaverine) over time, depending on different conditions (temperature and pH) in vitro and for the real dairy product – skimmed milk. The obtained results show that the studied strain significantly (P < 0.05) affects the number of individual amines, and the content of all amines has a decreasing character compared to the initial relative content of BAs at time zero. Furthermore, a statistical dependence (P < 0.05) of the rate of amine degradation on the combination of investigated factors was demonstrated. The presence and the activity of multicopper oxidase enzyme was also detected in this bacterial strain. This is the first known publication demonstrating multicopper oxidase activity in Lacticaseibacillus casei CCDM 198. Moreover, the studied strain is able to reduce the tested BAs in skimmed milk and would be a good candidate for degrading these toxic compounds in other dairy products, such as cheese. These findings could significantly enhance the food safety of dairy products.TBU in Zlín, (IGA/FT/2023/002); Ministerstvo Obrany České Republiky, MOČRInternal Grant of TBU in Zlin [IGA/FT/2023/002]; Ministry of Defence of the Czech Republi
Predictive control with measurable disturbances
No full textMost of the processes that need to be controlled are affected by external disturbances. In many cases, the disturbances can be measured. A control method that can successfully cope with disturbances which are known in advance is predictive control. The disturbances known in advance can be incorporated into calculation of the manipulated variable in predictive control. In many control applications, the disturbances are measurable but unknown in advance. In this case, the future course of the disturbance must be estimated on the basis of its past values. This paper proposes different approaches to estimation of future course of the measurable disturbances in predictive control. Particular approaches were compared by simulation. © 2022 IEEE
False alarms of the contact glass-break detectors caused by the multi-chamber window
No full textThe contact glass-break detector is very often marked as very unreliable and these models are not very popular in a security application. The aim of this article is to find out the bottleneck of the glass-break detectors and try to improve their functionality and reliability. The main function is based on the vibration caused by the impact on the glass panel and these vibrations are detected by the detector. However, the biggest issue is the absorption of the vibration by the glass panels and the plastic windows itself. This article should show the vibration transfer difference between the inner and outer glass panels in the multi-chamber window. This experiment should be done according to the current standardization by the two accelerometers on each side of the window. The results should be used for the further improvement of the design and reliability of the contact glass-break detectors on the market. © 2020 Danube Adria Association for Automation and Manufacturing, DAAAM. All rights reserved.IGA/CebiaTech/2020/003; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: LO1303, MSMT-7778/2014; European Regional Development Fund, ERDF: CEBIA-Tech ED2.1.00/03.008
Implementation of low pass filters with real opamps: Where is the limit?
No full textActive filters based on RC components together with operational amplifiers are quite common functional blocks to be met across different branches of electronics design. During the past, their topology has settled on several well-known and effective solutions. As an example, Sallen-Key or Multiple Feedback topology can be named. The designers can find a huge number of “cookbooks”. According to them they can find help with designing their filters. However, the theory described in these cookbooks usually fits ideal operational amplifiers in a good manner, but, unfortunately, the real parameters of the operational amplifiers may spoil the real behaviour of the design significantly. This problem occurs especially at very high frequencies that are typical for injection of electromagnetic interferences into low frequency signal lines. The authors of this paper have tested several antialiasing (low-pass) filter designs and provide results of measurement at real filters compared to the simulations. Moreover, they provide a discussion on why the results of the simulation do not fit the real behaviour of the filters and suggest improvements in the design of the low pass filters in that way so their utility value was improved. © 2019, Danube Adria Association for Automation and Manufacturing, DAAAM. All rights reserved.IGA/CebiaTech/2019/003; Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: LO1303, MSMT-7778/201
Performance measurement of the D-class audio amplifier
No full textClass-D audio amplifiers seem to be a perspective way of development of electronics as they can obtain excellent power efficiency together with good performance characteristics. Moreover, they can be easily integrated on a single chip, resulting in clear, comprehensive and non-reckless construction of the audio amplifier. Because the power efficiency is considerably high, some designs even do not need any heat sink, since the heat dissipation can be fully provided by the chip package. In this paper a construction of such an amplifier, being based on the integrated circuit TPA3122, is described. This construction has been developed at Tomas Bata University in Zlin, using conventional component base. Moreover, the paper provides a comparison of the measured performance of the amplifier to the theoretical values provided by the manufacturer of the chip. © 2018, Danube Adria Association for Automation and Manufacturing, DAAAM. All rights reserved.Ministerstvo Školství, Mládeže a Tělovýchovy, MŠMT: LO1303, MSMT-7778/2014; European Regional Development Fund, ERDF: CZ.1.05/2.1.00/03.008
Information system for manufacturing equipment diagnostics
No full textThe information system for assisting the manufacturing equipment diagnostics and repair based on the pictorial nested structure equipment model has been designed and experimentally tested. It is an open system with gradual structure refining and expanding possibility. Pictorial model can be supplemented with relevant data in form of documents, situation pictures, remarks and other data objects according to the experience gained from equipment operation and problem diagnostics procedures. That information system can be shared among authorized and registered users related somehow to the equipment concerned because it is designed as an application based on internet technologies and client/server structure
Influence of varieties and mulching on the quality and quantity of vegetable pepper yield
Get PDFThe influence of the cultivation method on green pepper fruits was investigated. Six pepper cultivars were planted using soil covered by brown mulching foil and in uncovered soil. Cultivation was maintained for two years providing the equivalent conditions of cultivation. The ascorbic acid content, total antioxidant capacity, total polyphenol content, soluble solids content and yield were observed and compared to mulching foil application, year of cultivation, pepper variety and order of harvest. The obtained results proved a statistically significant effect of mulching film in all tested varieties; the effects of year of cultivation and plant variety were also confirmed. The mulching film had a positive effect on pepper yield. The highest yield of peppers was grown on mulching foil in the variety 'Lungy'. The vitamin C content, total antioxidant capacity, total phenolic content and soluble solids content were demonstrably higher in the variant without mulching film. The highest levels of total polyphenol content and total antioxidant capacity were determined in the 'Yolo wonder' variety, the darkest colored cultivar. The highest content of vitamin C and soluble solids content were found in the 'Semaroh' variety grown without mulching film, however, this variety achieved the lowest yield growing with mulching foil.FEKT-S-20-6215, IGA/FT/2022/004TBU in Zlin [IGA/FT/2022/004]; project BUT in Brno [FEKT-S-20-6215
Engineering Se/N co-doped hard CNTs with localized electron configuration for superior potassium storage
No full textThe earth-abundant hard carbons have drawn great concentration as potassium-ion batteries (KIBs) anode materials because of their richer K-storage sites and wider interlayer distance versus graphite, but suffer from a low electrochemical reversibility. Herein, the novel Se/N co-doped hard-carbon nanotubes (h-CNTs) with localized electron configuration are demonstrated by creating unique N-Se-C covalent bonds stemmed from the precise doping of Se atoms into carbon edges and the subsequent bonding with pyrrole-N. The strong electron-donating ability of Se atoms on d-orbital provides abundant free electrons to effectively relieve charge polarization of pyrrole-N-C bonds, which contributes to balance the K-ion adsorption/desorption, therefore greatly boosting reversible K-ion storage capacity. After filtering into self-standing anodes with weights of 1.5–12.4 mg cm−2, all of them deliver a high reversible gravimetric capacity of 341 ± 4 mAh g−1 at 0.2 A g−1 and a linear increasing areal capacity to 4.06 mAh cm−2. The self-standing anode can still maintain 209 mAh g−1 at 8.0 A g−1 (93.3% retention) for a long period of 2000 cycles with a constant Se/N content. © 2022 Wiley-VCH GmbH.National Natural Science Foundation of China, NSFC: 21975074, 22208102; Shanghai Municipal Education Commission; Fundamental Research Funds for the Central Universities: 22220171800
Spiritual leadership and intellectual capital: mediating role of psychological safety and knowledge sharing
No full textPurpose – This study determines the nexus between spiritual leadership and psychological safety (PS). The authors explore the mediating role of PS and knowledge sharing to offer insights on how spiritual leadership can be advanced to better understand and support intellectual capital.
Design/methodology/approach – Data were collected using convenience sampling from the Pakistani automobile manufacturing industry. SPSS statistical software was used for descriptive analysis and hypotheses were tested by using the partial least square-structural equation modeling method.
Findings – The results demonstrate that spiritual leadership has a significant positive impact on PS; PS has a positive impact on knowledge sharing (KS) and KS has a positive impact on intellectual capital. Furthermore, PS mediates between spiritual leadership and KS. KS mediates between PS and human, social and organizational capital. Spiritual leadership also affects outside the boundaries of the organization and builds strong social relations with suppliers, buyers, etc.
Research limitations/implications – This study provides a deeper understanding of spiritual leadership in the context of KS and intellectual capital in the automobile sector of Pakistan.
Practical implications – This study encourages managers to nurture a philosophy of altruistic love that exerts a positive influence on employees. It will enrich their experience and promote a culture of KS.
Social implications – This study has social implications for organizations seeking to situate their inclusive goals in society. The findings of this study can help promote harmony as employees who feel psychologically safe are more willing to spread it in society.
Originality/value – This study theoretically contributes the big picture that how spiritual leadership contributes to intellectual capital and adds to the literature on the topicTomas Bata University in Zlin, TBU: IGA/FaME/2022/008Internal Grant Agency of Fame through Tomas Bata University in Zlin; [IGA/FaME/2022/008