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DEVELOPING CNN-AUGMENTED MODELS TO PREDICT CIELAB OUTCOMES POSTBLEACHING OF DENIM GARMENTS
Full text linkDenim garment production demands efficient design processes to minimize waste, costs, and production delays. Bleaching, among other finishing processes, holds paramount importance due to its numerous variables and substantial impact on product value. Artificial neural networks have great potential to achieve superior performance in anticipating various process outcomes. Their parameterized structure effectively captures non-linear relationships between input features. This study aims to effectively predict fabric outcomes by developing an artificial neural network (ANN) model supported by convolutional neural networks (CNN) to provide additional features derived from raw and semi-processed fabric images. The study represents a comparison of CNN powered models with a common predictive ANN as base model. Competing models incorporate various process variables and fabric properties, such as dying number and elasticity to predict changes in denim CIELab properties after bleaching. The process features of the model are the number of bleaching cycles, total process time, and concentration of sodium hypochlorite (representing the total amount of chemical used). The mean absolute percentage error is used as the performance measure between predictions and desired outputs. This research plays a significant role in enhancing agility in denim production by providing businesses with more efficient approaches to digitized denim bleaching and Research and Development processes in the textile industry
HYDROPHOBIC AND ANTIBACTERIAL TREATMENT OF JUTE FIBERS AND STUDY THEIR APPLICATION IN BIO COMPOSITES DEVELOPMENT
Full text linkBio-composites refers to composite materials made from sustainable materials. Jute fiber reinforced composites have inherent problem due to moisture and bacterial attack. The developed green composites are having resistance against environmental factors. At first, waste of jute fibres was pre-treated. Then two different approaches were adopted to enhance ageing factors of developed green composites. This research was proposed to go through methyltrimethoxysilane (MTMS), hydrophobic treatments, and for antipathogenic effect with ZnO nanoparticles were used. Morphological effects of chemical treatments on the jute fibers was analysed by scanning electron microscope. A significant decrease in moisture regain, increase in antibacterial zone of treated and untreated reinforcement samples was observed, when the concentration of chemical finish (methyltrimethoxysilane (MTMS) was 30 g/L and ZnO NPs also 30g/L was used. Subsequently the effects on the both mechanical properties and regain of moisture of composites reinforced with jute fiber was observed. At the concentration of 30 g/L a notable difference was spotted in moisture regain values of both treated and control (untreated) samples of reinforcement. Treated based composites regain less content of moisture and presents better mechanical properties (tensile strength and flexibility)
A logistic regression approach to long-term bankruptcy prediction: The role of financial and non-financial indicators
Full text linkThe main aim of the research is to examine the possibility of developing logistic regression (LR) model that could reliably predict the bankruptcy of Serbian companies three years in advance based on financial and non-financial variables. This is important both for business owners and external stakeholders. Owners can predict failure on time and define remedial measures and action plans in accordance with that. External stakeholders, on the other hand, can use these models to identify financial risks before deciding to start cooperation with a specific company. The main motive for the research stems from the lack of bankruptcy prediction models in the scientific community of the Republic of Serbia, especially when it comes to long-term prediction. It is necessary to predict bankruptcy early enough to be able to take measures. A prediction one year in advance, which is a common case in the existing literature, may be too late to preserve the business’s future. According to the authors’ findings, no long-term prediction models have been developed for the Serbian market. Existing traditional models are developed for foreign countries, meaning they are not suitable for developing countries like Serbia. The research sample includes 94 companies of all sizes and is balanced: half of the companies are healthy, and the other half are bankrupt. A total of 36 financial and 7 non-financial independent variables are included in the modelling. Financial analysis is done in MS Excel, while statistical analysis (logistic regression) is done in IBM’s SPSS program v. 26. The research results demonstrate that statistical and financial analyses are effective for bankruptcy prediction modelling, considering that the generated model has significant predictive (classification) power of 80%
KERSEN LEAF EXTRACT (Muntingia Calabura L.) FOR YARN DYEING APPLICATIONS IN LOMBOK-INDONESIAN WEAVING ARTISANS
Full text linkThis study aims to analyze the process of making natural dye extracts from Kersen leaves (Muntingia calabura L.) and the results of dyeing weaving yarn in weaving artisans in Lombok, Indonesia. This natural dye is expected to be an environmentally friendly alternative dye that uniquely enriches local cultural heritage. The cloth that has been dyed with kersen leaf extract is then fixed with three types of fixators, namely: alum solution (Al₂(SO₄)₃K₂SO₄24H₂O), lime solution (Ca(OH)₂), and ferrous sulfate solution (FeSO₄·7H₂O). The results of the study showed: 1) The technique of making natural dye extracts from kersen leaves carried out by the researcher through the extraction technique of materials with a composition of 200 grams of kersen leaves: 1,000 ml of water into 500 mL of extract solution while what the weavers did was 15 kg of kersen leaves: 30 litres of water into 15 litres of material solution that is ready to be used to dye woven yarn; 2) The use of fixators in addition to directing colors also locks the color on the dyed yarn so that it does not fade easily; the alum solution fixator produces brighter colors; the lime solution fixator produces colors that tend to brown; and the ferrous sulfate ban produces a darker color towards black. This finding recommends the use of kersen leaf extract as an alternative solution for environmentally friendly natural dyes to be used in yarn dyeing in the weaving industry
Carbon emission trading policy and green technological innovation in Chinese listed companies: A corporate reputation perspective
Full text linkThe carbon emission trading policy (CET) makes enterprises’ pollution information transparent and is an important environmental regulation tool for China to achieve the goal of “carbon peak” and “carbon neutrality.” Taking A-share listed companies in China’s Shanghai and Shenzhen stock exchange from 2008 to 2021 as a research sample, this paper chooses the implementation of China’s carbon emission trading policy in seven pilot regions as a quasi-natural experimental scenario and takes 2014 as the inception time of the policy to construct the difference-in-difference model with the fixed effect. The research then employs a multiple regression model and other statistical methods, such as an event study and placebo test, to examine the impact and mechanism of carbon emission trading policies on companies’ green technological innovation. The study reveals that CET significantly improves enterprises’ green technological innovation, attributed to weighing benefits against costs and preserving corporate reputation. Compared to purchasing carbon quotas for a long time, green technological innovation is a sustainable development strategy for enterprises, saving pollution costs and enhancing corporate reputation. The effect of CET on green technological innovation is more pronounced in larger enterprises, polluting industries, and regions where policy implementation is more rigorous. Enterprises that carry out green technological innovation to comply with CET can enjoy better reputations and lower financial costs. This study enriches and expands the research horizon of the impact of carbon trading policy on enterprises’ green technological innovation, examining it from both theoretical and empirical perspectives. It demonstrates that green technological innovation is a long-term strategic choice for enterprises, providing implications for achieving superior policy advantages. In addition, the research shows that CET alleviates information asymmetry and facilitates the disclosure of carbon information, offering an opportunity for external stakeholders to better oversee their corporations
Z rodzinnego Turnova za baranami Liberetora. Pułkownik in memoriam Ludvík Košek
No full textThe study summarizes the life story of a Czechoslovak member of the British Royal Air Force. Ludvík Košek belongs to the most prominent natives of the North Bohemian town of Turnov. He is significantly associated with the pre-war history of the Turnov society of the Sokol sports organization and the LTC Turnov hockey team, within which he performed consistently at the regional level for several years and in various sport disciplines. After the Nazi occupation in March 1939, as aformer member of the First Republic Czechoslovak Air Force, he belonged to the group of those who decided to leave the Protectorate of Bohemia and Moravia with the aim of joining the anti-Nazi resistance. He served in Poland, France and Great Britain and as a gunner and later a pilot in the British Royal Air Force, he significantly contributed to the liberation of the occupied homeland. His long operational activity is exceptional in the area of today‘s Liberec Region. However, he died with his entire crew while returning from an operational flight on July 13, 1944. Proof of his importance as alocal personality has been the post-war effort to maintain his legacy not only in his hometown.Thema ist die Lebensgeschichte von Ludvík Košek, der aus Turnau/Turnov stammte und Mitglied der britischen Royal Air Force war. Im Mittelpunkt steht die Beschreibung der operativen Tätigkeiten dieses antinazistischen Widerstandskämpfers während des Zweiten Weltkriegs, zunächst als Bordschütze und später als Pilot der 311. tschechoslowakischen Bomberstaffel (Liberator), der am 13. Juli 1944 bei einem Kampfflug getötet wurde. Der Text befasst sich zudem mit anderen Abschnitten seines Lebens, insbesondere mit seiner Jugend, als er als Mitglied der Sportorganisation Sokol und des Vereins LTC Turnov regelmäßig an der Spitze regionaler Sportveranstaltungen stand. Ferner werden auch die Bemühungen reflektiert, das Vermächtnis dieses antinazistischen Widerstandskämpfers durch seine Familie, die Vereine und die Stadt Turnov in der Nachkriegszeit in Erinnerung zu halten. Bei der Erstellung der Studie wurden die üblichen Verfahren zur Erstellung eines wissenschaftlichen Textes angewandt, nämlich Analyse, Vergleich und Synthese historischer Quellen. Diese wurden aus tschechischen und ausländischen Archiven und Bibliotheken beschafft und durch Erkenntnisse aus bereits veröffentlichter Literatur ergänzt. Einen bedeutenden Einfluss auf die Form des Textes hatten auch Quellen, die sich im Besitz von Mitgliedern der Familie von Ludvík Košek befinden. In diesem Umfang ist die Biografie dieses Fliegers bisher noch nicht behandelt worden, zumal diese Arbeit eine ganze Reihe bisher unbekannter Informationen nicht nur in Bezug auf die Kampfflüge, die sportlichen Leistungen und die Bemühungen um sein Andenken bringt, sondern auch versucht, einige bereits veröffentlichte Informationen angemessen und kritisch zu bewerten. Trotz des Versuchs, ein möglichst breites Spektrum historischer Quellen einzubeziehen, bietet der Text Raum für weitere Ergänzungen, zum Beispiel im Bereich des Lebens von Kosek vor der Besetzung im März 1939 und insbesondere für eine vertiefte Erforschung seiner Aktivitäten in der Turnauer Sokol-Einheit oder des Alltagslebens dieses Fliegers in Frankreich und Großbritannien, die weiterer detaillierter Untersuchungen bedürfen.Studium Z rodzinnego Turnova za baranami Liberatora opisuje losy życiowe turnovskiego rodaka oraz członka brytyjskiego Lotnictwa Królewskiego Ludvíka Koška. Jego główna część koncentruje się na opisie działań operacyjnych tego uczestnika antynazistowskiego ruchu oporu podczas II wojny światowej, najpierw jako strzelca podkładowego, a później jako pilota 311. Czechosłowackiego Dywizjonu Bombowego, który zginął podczas pełnienia misji bojowej w dniu 13 lipca 1944r. Tekst zajmuje się również innymi aspektami jego życia, zwłaszcza jego młodością, kiedy to jako członek organizacji sportowej Sokol i oddziału LTC Turnov zdobywał regularnie czołowe miejsca w regionalnych wydarzeniach sportowych. Oprócz innego odzwierciedla również próbę przypomnienia spuścizny w okresie powojennym tego antynazistowskiego opozycjonisty ze strony rodziny, stowarzyszeń oraz miasta Turnov. Podczas studium zastosowano standardowe procedury podczas tworzenia specjalistycznych tekstów, takie jak analiza, komparacja i synteza źródeł historycznych. Pozyskiwano je z czeskich i zagranicznych archiwów i bibliotek, które były uzupełniane informacjami z opublikowanej dotychczas literatury. Istotny wpływ na kształt tekstów miały również źródła będące w posiadaniu rodziny Ludvíka Koška. W takim zakresie temat życia wspomnianego pilota nie został jak dotąd opracowany i przynosi cały szereg nie znanych dotąd informacji, nie tylko w odniesieniu do wykonanych misji bojowych, osiągnięć sportowych i usiłowań o ich upamiętnienie, ale stara się też sprostować i krytycznie ocenić niektóre opublikowane już informacje. Pomimo starań o wykorzystanie jak najszerszego spektrum źródeł historycznych, tekst stwarza również przestrzeń do dalszego jego powiększania, na przykład w zakresie życia Koška przed okupacją w marcu 1939, a zwłaszcza do głębszych badań jego działalności w turnovskim oddziale Sokol oraz życia codziennego tego pilota we Francji i Wielkiej Brytanii, co wymaga dalszego szczegółowego studium
A program of non-traditional physical activities developing motor skills and motivation to move in 6th grade elementary school students
No full textBakalářská práce se zabývá návrhem a realizací pohybového programu založeného na
netradičních pohybových aktivitách, který je určen žákům 6. třídy základní školy. Cílem práce
bylo ověřit, zda tyto aktivity mohou přispět k rozvoji motorických dovedností a zvýšení
motivace žáků k pohybu. Teoretická část práce se věnuje problematice pohybové gramotnosti,
vztahu žáků k tělesné výchově a vymezení pojmu netradiční pohybové aktivity.
V praktické části byl pomocí dotazníkového šetření zjišťován vztah žáků ke sportu, tělesné
výchově a jejich postoje k méně tradičním činnostem. Na základě výsledků byl vytvořen a
realizován program netradičních pohybových aktivit, který byl aplikován ve výuce tělesné
výchovy. Součástí programu byly hry a aktivity podporující spolupráci, kreativitu i rozvoj
základních pohybových schopností.
Z výsledků vyplynulo, že žáci vnímají netradiční aktivity pozitivně a uvádějí, že jim přinášejí
nové zážitky a rozvoj nových dovedností. Program byl žáky přijat s velkým zájmem a přispěl
ke zvýšení jejich aktivity v hodinách tělesné výchovy. Práce ukazuje, že zařazení netradičních
činností do školní výuky může být efektivní cestou k podpoře pozitivního vztahu žáků k pohybu.The bachelor's thesis focuses on the design and implementation of a physical activity program
based on non-traditional movement activities intended for 6th-grade primary school pupils.
The aim of the thesis was to verify whether these activities could contribute to the
development of motor skills and increase pupils' motivation to engage in physical activity.
The theoretical part of the thesis deals with physical literacy, pupils' relationship to physical
education, and the definition of non-traditional physical activities.
In the practical part, a questionnaire survey was used to investigate pupils' attitudes towards
physical education, sports, and less common movement activities. Based on the findings, a
program of non-traditional physical activities was created and implemented within physical
education lessons. The program included games and activities that supported cooperation,
creativity, and the development of basic motor skills.
The results showed that pupils perceive non-traditional activities positively and report that
they bring new experiences and skill development. The program was well received and
contributed to increased engagement in physical education classes. The thesis shows that
incorporating non-traditional activities into school education can be an effective way to support pupils' positive attitude toward movement
Development and verification of an in vitro bone model for testing polymeric tissue scaffolds
No full textTato práce pojednává o vývoji in vitro modelu kosti pro detailní testování kostních náhrad, aby se předešlo nadměrnému testování na zvířatech. Buněčné monokultury používané pro in vitro testování kostních náhrad postrádají komplexnost celé tkáně či organismu, takže získané výsledky mají omezenou vypovídací hodnotu. Ko-kultury různých typů kostních buněk umožňují přirozenou signalizaci a komunikaci, což lépe napodobuje hojení v in vivo prostředí. Hlavními aktéry hojení jsou osteoklasty (OCs), degradující poškozenou tkáň, a osteoblasty (OBs), tvořící novou tkáň. Tyto dva buněčné typy byly použity pro vývoj in vitro modelu kosti. Buňky byly izolovány z potkanů, byl potvrzen jejich fenotyp a byly optimalizovány podmínky ko-kultury, tj. kultivační médium, poměr buněčných typů při nasazení a použité suplementy do média. Funkčnost in vitro modelu byla ověřena pomocí nanovláken z poly--kaprolaktonu (PCL) obsahujících 0, 10 a 20 % w/v hydroxyapatitu (HAp) elektrostaticky zvlákněných ve střídavém (AC) nebo stejnosměrném (DC) proudu, a chování ko-kultury bylo porovnáno s rutinně používanou monokulturou OBs. PCL bez HAp elektrostaticky zvlákněný v DC vykazoval ve srovnání s ostatními nanovlákennými materiály menší medián průměru vláken, úzký rozsah hustoty pravděpodobnosti poloměru pórů a malý kontaktní úhel. Tyto parametry patrně vedly k lepší adhezi buněk, osteoklastogenezi a osteogenezi. Také byly zaznamenány rozdíly v chování buněk mezi ko-kulturou a monokulturou OBs. Kostní ko-kultura byla dále použita k testování účinku nanovláken uvolňujících Alendronát (ALN), lék na osteoporózu, určený k lokální léčbě osteoporózy v místě zlomeniny. Byla hledána koncentrace ALN, která není cytotoxická, ale inhibuje osteoklastogenezi a poté byla vytvořena nanovlákna s ALN nebo v kombinaci s HAp, který uvolňování ALN zpomalil. Byly připraveny ko-kultury z osteoporotických a zdravých (kontrolních) potkanů, avšak nebyl pozorován žádný zjevný rozdíl v chování buněk v reakci na nanovlákna uvolňující ALN různou rychlostí. Pozorovali jsme však nižší metabolickou aktivitu a proliferaci a vyšší osteogenní a osteoklastogenní differenciaci ko-kultur z osteoporotických potkanů ve srovnání s ko-kulturami ze zdravých potkanů. Závěrem lze říci, že byl vyvinut in vitro model kosti z ko-kultury OCs a OBs a rozdíl v chování buněk ve srovnání s monokulturou OBs ukázal důležitost jeho použití pro in vitro testování kostních náhrad.This thesis deals with developing an in vitro bone model for detailed testing of bone substitutes to avoid excessive animal testing. The cell monocultures used lack the complexity of a whole tissue or an organism, so the results obtained are of limited information. Co-cultures of bone cell types enable natural signaling and communication that better mimic the healing in the in vivo environment. The main players in bone healing are osteoclasts (OCs) degrading the damaged tissue, and osteoblasts (OBs) forming new tissue. These two cell types were used to develop the in vitro bone model. Cells were isolated from rats, their phenotype was confirmed, and the co-culture conditions, i.e., culture medium, the seeding ratio between the cell types, and supplements used, were optimized. The functionality of the in vitro bone model for testing bone substitutes was verified with poly--caprolactone (PCL) nanofibers containing 0, 10, and 20% w/v hydroxyapatite (HAp) electrospun by alternating current (AC) or direct current (DC) methods and compared with the routinely used OBs monoculture. PCL without HAp electrospun by DC showed smaller median fiber diameter, a narrow range of probability density of pore radius, and a low contact angle compared to other nanofibers. These parameters probably led to better cell adhesion, osteoclastogenesis, and osteogenic differentiation compared to other nanofibrous materials. Differences in cell behavior were observed between the co-culture and the OBs monoculture. The bone co-culture was also used to test the effect of nanofibers releasing Alendronate (ALN), an osteoporosis drug, designed to treat osteoporosis locally at the fracture site. A concentration of ALN that is not cytotoxic but inhibits osteoclastogenesis was sought. Nanofibers were prepared with ALN alone or in combination with HAp, which slows ALN release. No apparent difference was observed between the nanofibers with different ALN release kinetics on co-cultures from osteoporotic and healthy (control) rats. However, we observed lower metabolic activity and proliferation and higher osteogenic and osteoclastogenic differentiation in co-cultures from osteoporotic rats compared to healthy rats. In conclusion, the in vitro bone model consisting of a co-culture of OCs and OBs was developed, and the differences in cell behavior compared to OBs monoculture showed the importance of its use for in vitro testing of bone substitutes
Mahalanobis distance and Stutzer ratio modelling in emerging markets portfolios
No full textThis study examines the performance of multi-asset portfolios in global emerging markets, emphasizing their exposure to systemic risk and risk-adjusted returns. The analysis encompasses portfolios from regions such as Southeast Asia, the Middle East and Central Asia, Central and Eastern Europe, Africa, and Latin America. The research uses daily data, covering a 10 years period. Two advanced methodologies are applied in the portfolio construction – the Mahalanobis distance and the Stutzer ratio. The financial turbulence index constructed for the systemic risk measurement reveals a pronounced allocation bias toward a single asset, driven by its distinctive attributes. Interestingly, the asset with the highest weight in the portfolio originates from frontier markets, which are less integrated into the global financial system and thus more insulated from global economic shocks. The Stutzer ratio, through its calculation of the decay parameter theta, provides insights into whether an emerging market portfolio is characterized by high volatility and frequent market fluctuations or is more aligned with long-term investment strategies that emphasize stability and consistent performance. The results indicate that all emerging markets portfolios have higher Stutzer ratio than the developed portfolio, which indicates better risk-adjusted results. However, the theta parameter is mostly lower in the emerging markets portfolios, suggesting higher risk in these markets. The highest Sharpe ratio is found in the African countries portfolio, while the best portfolio, when using the more advanced Stutzer ratio, is with Latin American countries. This study provides insightful guidance for international investors exploring opportunities in emerging markets, focusing on systemic risk and evaluating returns through a risk-adjusted lens
