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This study aims to get rid of non-degradable polyvinyl chloride (PVC) waste as well as sunflower seed cake (SSC) waste by preparing eco-friendly composites from both in different proportions to reach good mechanical and insulating properties for antimicrobial and antistatic applications.

Eco-friendly composite films based on waste polyvinylchloride (WPVC) and SSC of concentrations (0, 10, 20, 30 and 40 Wt.%) were prepared using solution casting method. Further, the effect of sunflower seed oil (SSO) on the biophysical properties of the prepared composites is also investigated. Fourier transform infrared spectroscopy, X-ray diffraction (XRD), scanning electron microscope, mechanical, thermal, dielectric properties were assessed. Besides, the antimicrobial and biodegradation tests were also studied.

The crystallinity increases by rising SSC concentration as revealed by XRD results. Additionally, the permittivity (ε′) increases by increasing SSC filler and SSO as well. A remarkable increase in dc conductivity was attained after the addition of SSO. While raw WPVC has very low bacterial activity. The composite films are found to be very effective against staphylococcus epidermidis, staphylococcus aureus bacteria and against candida albicans as well. On the other hand, the weight loss of WPVC increases by adding of SSC and SSO, as disclosed by biodegradation studies.

The study aims to reach the optimum method for safe and beneficial disposal of PVC waste as well as SSC for antistatic and antimicrobial application.

Cryptocurrency markets are gaining popularity, with over 23,000 cryptocurrencies in 2023 and a total market valuation of 870.81 billion USD in 2023. With its increasing popularity, cryptocurrencies are also susceptible to volatility. Predicting the price with the least fallacy or more accuracy has become the need of the hour as it significantly influences investment decisions.

This study aims to create a dynamic forecasting model using the ensemble method and test the forecasting accuracy of top 15 cryptocurrencies’ prices. Statistical and econometric model prediction accuracy is examined after hyper tuning the parameters. Drawing inferences from the statistical model, an ensemble model using machine learning (ML) algorithms is developed using gradient-boosted regressor (GBR), random forest regressor (RFR), support vector regression (SVR) and multi-layer perceptron (MLP). Validation curves are utilized to optimize model parameters and boost prediction accuracy.

It is found that when the price movement exhibits autocorrelation, the autoregressive integrated moving average (ARIMA) model and the ensemble model performed better. ARIMA, simple linear regression (SLR), random forest (RF), decision tree (DT), gradient boosting (GB) and multi-model regression (MLR) ensemble models performed well with coins, showing that trends, seasonality and historical price patterns are prominent. Furthermore, the MLR approach produces more accurate predictions for coins with higher volatility and irregular price patterns.

Although the dataset includes crisis period data, anomalies or outliers are yet to be explicitly excluded from the analysis. The models employed in this study still demonstrate high accuracy in predicting cryptocurrency prices despite these outliers, suggesting that the models are robust enough to handle unexpected fluctuations or extreme events in the market. However, the lack of specific analysis on the impact of outliers on model performance is a limitation of the study, as it needs to fully explore the resilience of the forecasting models under adverse market conditions.

The present study contributes to the body of literature on ensemble methods in forecasting crypto price in general, potentially influencing future studies on price forecasting. The study motivates the researchers on empirical testing of our framework on various asset classes. As a result, on the prediction ability of ensemble model, the study will significantly influence the decision-making process of traders and investors. The research benefits the traders and investors to effectively develop a model to forecast cryptocurrency price. The findings highlight the potential of ensemble model in predicting high volatile cryptocurrencies and other financial assets. Investors can design the investment strategies and asset allocation decisions by understanding the relationship between market trends and consumer behavior. Investors can enhance portfolio performance and mitigate risk by incorporating these insights into their decision-making processes. Policymakers can use this information to design more effective regulations and policies promoting economic stability and consumer welfare. The study emphasizes the need for using diversified model to understand the market dynamics and improving trading strategies.

This research, to the best of our knowledge, is the first to use the above models to develop an ensemble model on the data for which the outliers have not been adjusted, and the model still outperformed the other statistical, econometric, ML and deep learning (DL) models.

加密貨幣市場越來越受歡迎; 於2023年,不同種類的加密貨幣為數已超過23,000種; 同年,它們的總市場估值為八千七百零八點壹億美元。雖然加密貨幣越來越受歡迎,但它們仍然容易受到波動性的影響。預測謬誤減至最少的價格或作出更準確的價格預測就成為某些特定時刻的首要事項,這是因為投資決策會顯著地受到這些預測的影響。

研究人員擬以集成學習方法來創造一個動態預測模型,並以此模型測試預測15個頂尖加密貨幣價格的準確性。 研究人員調校超參數後,便審查統計及計量經濟學模式的預測準確性。研究人員基於從統計模式作出的推斷,研製一個使用機器學習算法的集成模型。研究人員在研製這個集成模型時,使用了梯度提升迴歸變量、隨機森林迴歸、支持向量迴歸和多層感知器。 驗證曲線被用來優化模型參數,以及提高預測的準確性。

研究人員發現,當價格變動展示自相關時,差分整合移動平均自我迴歸模型和集成模型會表現得更好; 另外,若使用加密貨幣,差分整合移動平均自我迴歸模型、簡單線性迴歸、隨機森林、決策樹、梯度提升和多模型迴歸集成模型會有良好的表現。再者,就波動性較高和價格模式不規則的加密貨幣而言,採用多重線性迴歸的方法會使預測更為準確。

據我們所知,這是首個研究,以上述的各個模型來研發一個集成模型,而這個集成模型,雖建基於異常值並未調整的數據,但它的表現卻比其它的統計、計量經濟學、多重線性和深度學習等的模型更為優良。

Reviewing the existing literature in the field of e-learning success reveals a considerable number of studies that primarily investigate the causal relationships proposed by the DeLone and McLean (D&M) information system (IS) success model. However, the various relationships in the D&M model have found different levels of support or even contradictory results within the empirical literature. To synthesize the existing knowledge in the field of e-learning success, the authors have conducted a meta-analysis of e-learning success studies using D&M to combine the quantitative results and validate the model in this field. Furthermore, a moderator analysis involving user types was performed to examine the situation under which they may have different effects.

For this purpose, through a systematic review of the studies, 44 independent studies were selected from 29 qualified related journals. In order to analyze the quantitative results of the studies, the meta-analysis of the effect sizes of the casual relationships in the D&M model has been used.

The findings indicated that all relationships of the model were supported. It was also revealed that the extent of effect sizes of the examined relationships depends on the type of user. Except for one relationship (user satisfaction and net benefit), all effect sizes of employees were more than those of students and teachers.

This meta-analysis reviewed the relationships found in the literature on D&M constructs in e-learning contexts. This study better explains the e-learning success factors by consolidating contradictory findings in the past researches and contributes to the existing e-learning success literature. The findings can assist educational institutions and organizations in decision-making because the findings resulting from the meta-analysis are more consistent than previous primary researches.

Despite the widespread use of the D&M model in the field of e-learning success, no study has yet consolidated the quantitative findings of these studies and the current field abounds in some controversies and inconsistent findings. This paper integrates the results of empirical studies that examined the relationships within the D&M model. The main contribution of this paper, which is the first of its kind, is to apply meta-analysis to reconcile the conflicting findings, investigate the strengths of the relationships in the D&M model and provide a consolidated view.

This chapter explores how department stores came at the end of the 19th century to be at the origin of what is now called “fashion tourism.” Contributing to a new “geography of commerce,” it highlights the role of the space of the department store both as a place of conspicuous fashion consumption and tourism. Further, it demonstrates how Parisian department stores helped consolidate Paris's place as the capital of fashion and luxury. Far from being only places to buy the latest in fashion, the latter became indeed a symbol as quintessentially Parisian as the Eiffel Tower and as necessary to visit for the “Paris experience.”

A collection of essays by a social economist seeking to balance economics as a science of means with the values deemed necessary to man′s finding the good life and society enduring as a civilized instrumentality. Looks for authority to great men of the past and to today′s moral philosopher: man is an ethical animal. The 13 essays are: 1. Evolutionary Economics: The End of It All? which challenges the view that Darwinism destroyed belief in a universe of purpose and design; 2. Schmoller′s Political Economy: Its Psychic, Moral and Legal Foundations, which centres on the belief that time‐honoured ethical values prevail in an economy formed by ties of common sentiment, ideas, customs and laws; 3. Adam Smith by Gustav von Schmoller – Schmoller rejects Smith′s natural law and sees him as simply spreading the message of Calvinism; 4. Pierre‐Joseph Proudhon, Socialist – Karl Marx, Communist: A Comparison; 5. Marxism and the Instauration of Man, which raises the question for Marx: is the flowering of the new man in Communist society the ultimate end to the dialectical movement of history?; 6. Ethical Progress and Economic Growth in Western Civilization; 7. Ethical Principles in American Society: An Appraisal; 8. The Ugent Need for a Consensus on Moral Values, which focuses on the real dangers inherent in there being no consensus on moral values; 9. Human Resources and the Good Society – man is not to be treated as an economic resource; man′s moral and material wellbeing is the goal; 10. The Social Economist on the Modern Dilemma: Ethical Dwarfs and Nuclear Giants, which argues that it is imperative to distinguish good from evil and to act accordingly: existentialism, situation ethics and evolutionary ethics savour of nihilism; 11. Ethical Principles: The Economist′s Quandary, which is the difficulty of balancing the claims of disinterested science and of the urge to better the human condition; 12. The Role of Government in the Advancement of Cultural Values, which discusses censorship and the funding of art against the background of the US Helms Amendment; 13. Man at the Crossroads draws earlier themes together; the author makes the case for rejecting determinism and the “operant conditioning” of the Skinner school in favour of the moral progress of autonomous man through adherence to traditional ethical values.

Globally, mobile technology is a significant factor influencing how libraries are changing the ways of delivering services to today’s users. This paper aims to explore academic librarians’ perceptions of the usefulness of mobile technology in delivering library services and the efforts required for its successful adoption.

The study was conducted within an interpretive paradigm. The research objectives were underpinned by the unified theory of acceptance and use of technology as a theoretical framework. Data were collected through semi-structured interviews and analyses using NVIVO for thematic analysis.

Results show that, in general, academic librarians support the use of mobile technology to provide services such as access to eBooks and Journals, Online Public Access Catalogue, Bookmyne application, information literacy consultations and training. Library managers, fellow librarians and users were identified as encouraging the adoption of mobile technology to enhance library services. The paper further confirms that the successful adoption of mobile technology requires some effort. However, due to some of the challenges presented in the study, a majority of respondents felt that their libraries are not yet ready to fully embrace mobile technology the way it is envisioned in today’s world.

The study endeavours to address the divergence between students and academic librarians’ viewpoints regarding the application of mobile technology in the provision of library services.

This paper highlights numerous ways that academic librarians could adopt and embrace mobile technology, which can benefit both academic libraries and other institutions of higher learning. The knowledge presented in this paper could assist academic librarians in assessing their institutions’ vulnerabilities, challenges and strengths in using mobile technologies to provide library services.