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Unveiling exceptional thermoelectric performance of two dimensional Zintl AMg2X2 (A = Ca, Sr, or Ba; X = As, Sb, or Bi) compounds
No full textTwo-dimensional (2D) thermoelectric materials have gained increasing attention as a promising solution to address the challenges associated with power generation. Interestingly, studies on some of the Zintl phase CaAl2Si2-type compounds have shown optimistic thermoelectric properties, including Zintl phase AMg2X2 (A = Ca, Sr, or Ba; X = As, Sb, or Bi). Here, we performed first-principles calculations to investigate the structural stability, electronic properties, and thermoelectric properties of nine 2D monolayer AMg2X2 compounds. Phonon dispersions of all monolayer compounds confirm the dynamic stability, implying the possibility of experimental synthesis. Regarding the electronic properties under the hybrid functional approach (HSE06), five compounds (CaMg2As2, CaMg2Bi2, SrMg2As2, SrMg2Bi2, and BaMg2Bi2) show direct bandgaps while the rest are indirect bandgap semiconductors, with CaMg2Sb2 having the largest bandgap of 1.956 eV. To provide an estimate of the maximum operating temperatures for thermoelectric applications, an existing machine-learning based tool to determine the melting temperatures of all materials, resulting in a range of values within 1200 to 1500 K. Remarkably, the calculated figure-of-merit (ZT) values using HSE06 coupled with the Boltzmann transport theory show that the best n-type (p-type) material is CaMg2Sb2 (CaMg2As2) with a ZT value of 5.225 (1.349) at 1300 K, well-below their melting temperatures. These 2D compounds exhibit excellent ZT values compared to the currently synthesized thermoelectric materials. With the recent success of synthesizing 2D Zintl compounds, our theoretical findings will promote the importance and provide guidance on experimentally synthesizing 2D monolayer AMg2X2 for possible thermoelectric applications
The mechanical properties of ceramic matrix composites composed of polysilazane-derived silicon oxycarbonitride ceramic incorporated with alumina powder
No full textIn this study, polysilazane preceramic precursor is utilized as a raw material to develop ceramic-based composite materials. Polymer-derived ceramics exhibit excellent thermal stability, mechanical properties, and high corrosion resistance, making them well-suited for the development of ceramic-based composite materials.
The main objective of this study is to develop two different ceramic-based composite materials. The first uses a liquid polymeric precursor polysilazane (PSZ), (Durazane 1500 slow cure) as the base material. Aluminum oxide powder is added to enhance the mechanical strength of the composite ceramic material. The composite ceramic samples are then subjected to a pyrolysis temperature of 1000\uc2\ub0C. The densities and coefficient of thermal expansion of the pyrolyzed composite ceramic samples are measured. The second type involves preparing SiCNO ceramic powder using the same liquid polymeric precursor, and then mixes the powder with aluminum oxide powder (Al2O3). The resulting mixture is pressed to form ceramic bulk. These ceramic materials are then subjected to different pyrolytic temperatures (1000\uc2\ub0C, 1100\uc2\ub0C, 1200\uc2\ub0C) in order to compare their mechanical properties, including hardness, density, compressive strength, compressive modulus, and flexural strength.
The experimental results show that (1)Xwt.%Al2O3-PSZ-1000 ceramic samples are mixed with the base material, polysilazane (PSZ). Their coefficient of thermal expansion (CTE)(100~950\uc2\ub0C) and density increase with higher proportions of aluminum oxide powder. (2)Al2O3-Xwt.% SiCNO ceramic samples are incorporated with the base material, aluminum oxide powder (Al2O3). Adding a higher amount of SiCNO ceramic powder results in a decrease in the density and shrinkage rate of the aluminum oxide ceramic. At a pyrolytic temperature of 1000\uc2\ub0C, 10wt.% SiCNO powder with the aluminum oxide powder (Al2O3-10 wt.% SiCNO) enhances its hardness by 8.6%. In compression testing, Al2O3-10 wt.% SiCNO results in an increase in the compressive strength of the aluminum oxide ceramic by 34.5% and an increase in the compressive modulus by 41.3%. For three-point bending flexural tests, adding SiCNO ceramic powder improves the flexural strength of the aluminum oxide ceramic. Specifically, at a pyrolytic temperature of 1100\uc2\ub0C, Al2O3-20 wt.% SiCNO improves the flexural strength of the aluminum oxide ceramic by 151.1%. The research findings demonstrate that the addition of SiCNO ceramic powder to aluminum oxide ceramic can effectively enhance the mechanical properties of aluminum oxide by lowering the density from 3.95% to 15.8%.
The experimental results demonstrate that the addition of 10wt.% SiCNO ceramic powder to aluminum oxide pyrolyzed at 1000\uc2\ub0C have the most significant improvement of the mechanical properties of aluminum oxide. Compared to the aluminum oxide specimen sintered at 1000\uc2\ub0C, the hardness, compressive strength, compressive modulus, flexural strength and flexural modulus improves by 8.60%, 34.51%, 41.34%, 45.18%, and 49.76%, respectively. Also, its density reduces by 3.95%, and the specimen shrinkage rate is about 0.89%
Bataille's 'Nonknowledge' and Human Existence from the Stance of Mathematics
No full textWhen Hegel\ue2s knowledge has exhausted everything and history has ended, the world is no longer active. How should people live in it? When human existence is imagined as a closed individual, where the human activity is? How is communication between closed human beings and others possible? This study proves that Bataille\ue2s thought of nonknowledge transcends the structure closed by Hegel\ue2s negative dialectics through set theory. In addition, it further points out that the loophole in Hegel\ue2s structure is the death he missed, brings death back to people\ue2s vision, and transforms humans from the closed being into the fluid state of existence. Besides, this study reveals the key difference between NOTHING and the void in relation to death, and further uses topology and limit to present the locus of void that is difficult to capture. Finally, in the topological space, this study shows that the key to communication between humans is the void, and demonstrates the communication process of the community. This study provides a new look at the communication structure of human existence, others and the world, reactivates life and the world, and provides a powerful resource for understanding Bataille\ue2s thought. Meanwhile, this study also shows that mathematical thought has a huge impact on philosophical thought. Furthermore, the great influence can enhance the vitality of contemporary philosophical thought and open up richer developmental prospects
The Impact of Internet Celebrities on Consumer Intention to Repurchase in Online Group Buying.
No full textIn the era of widespread social media, influencer marketing has gradually become an essential element in marketing strategies. The influencer-led group buying model has permeated various consumer groups. Through influencers' recommendations and live sales, consumers' shopping experiences and purchasing decisions are deeply affected. The collaboration model between influencers and brands, as well as the rise of influencer-created brands, further showcase the rapid development of this trend. Therefore, this study aims to investigate whether influencers influence consumers' repurchase intentions for online group purchases.
This study explores the impact of influencers on consumers' repurchase intentions for online group purchases, utilizing the Stimulus-Organism-Response (S-O-R) theory as a foundation. The research looks into stimulus factors such as 'expertise', 'appeal', 'reliability', 'price promotion', and 'information richness', with 'satisfaction', 'trust', and 'perceived usefulness' as the organism, measuring the consumer's 'repurchase intention' response. The survey adopted the Likert Scale as a measurement scale, with the survey population being consumers who had purchased influencer-led group buying products. The online survey yielded a total of 296 valid responses.
The results show that consumer satisfaction, trust, and perceived usefulness of online group purchases are positively influenced by the influencer's expertise, appeal, reliability, group purchase price promotion, and richness of group purchase information, which in turn affect consumers' repurchase intentions for online group purchases. The findings and results of this study contribute to understanding how influencer marketing influences consumer behavior, providing effective marketing strategy guidance and direction for influencers, merchants, and online group buying activities
A Study on the Relationship Between Financial Literacy and Financial Behavior of Culture and Arts Workers
No full textThe culture and arts industries in Taiwan are different from other industries in that there is a high proportion of atypical employees, who commonly face risks such as low wages, insufficient social security, a lack of career development, and a lack of labor rights. Since 2020, due to the impact of Covid-19, culture and arts activities that have come to a standstill have directly affected the livelihoods of culture and arts workers. Therefore, having good financial literacy, attitudes, and knowledge is crucial for culture and arts workers. How to effectively manage limited income and engage in flexible financial planning is a common issue facing our society today.
Through literature review, it is found that financial literacy and financial behavior are both influenced by personal background, and there is a significant positive correlation between financial literacy and financial behavior. Therefore, based on the theoretical frameworks proposed by Jump$tart (2017) and O'Neill & Xiao (2003), the study designed a Likert five-point scale questionnaire targeting culture and arts workers. Statistical analyses such as descriptive statistics, independent samples t-tests, one-way ANOVA, Pearson correlation, and multiple regression analysis were employed to verify the research hypotheses.
The results show that: (1) Financial literacy of culture and arts workers vary significantly depending on gender, age, parenting status, and monthly income. (2) Financial behavior of culture and arts workers vary significantly depending on gender, age, marital status, parenting status, monthly income, and years of work experience. (3) There is a positive correlation between financial literacy and financial behavior of culture and arts workers. The higher the financial literacy, the better their financial behavior tends to be. (4) Culture and arts workers with higher financial literacy can predict better financial behavior. Finally, based on the research results, specific recommendations are provided for the culture and arts workers and future research. The aim is to encourage culture and arts workers to prioritize financial literacy, actively seek financial knowledge and skills, regularly evaluate financial behavior, and engage in effective financial planning to achieve financial goals
Exploring the Relationship between Company Safety Culture and Safety Incidents in Various Types of Ownership Arrangements
No full textThe purpose of this study is to explore the impact of safety culture in different types of ownership companies on safety incidents. The paper mentions that due to the specific nature of chemical products, industrial accidents can pose serious threats to human life, property, and the environment. Therefore, chemical companies must prioritize safety management and the development of safety culture. The paper also highlights some recent severe industrial accidents, emphasizing the importance of studying the differences in safety culture and safety incidents among different ownership types of chemical companies.
This study aims to compare the differences in safety culture and safety incidents among different ownership types of chemical companies (Companies A and B), examine the various aspects of their safety culture development, and assess their impact on safety incidents. Specifically, this study will investigate process safety management (PSM), safety pyramid culture, safety awareness development (safety ambassador activities, Swiss cheese model), as well as behavior observation/walkthrough audits, near-miss incidents, and incident reporting in the construction of safety culture in petroleum and chemical companies.
In today's society, industrial safety has become an integral part of business operations. Many companies are continuously striving to improve safety levels to ensure the health and well-being of their employees. According to interview data, both Company A and Company B place great importance on establishing a safety culture and have implemented corresponding plans and actions. To enhance safety culture, interviewees from Companies A and B believe that possessing professional knowledge, adhering to operational discipline, demonstrating managerial leadership, and embracing digitalization play key roles in establishing a robust industrial safety culture and reducing the occurrence of safety incidents.
Overall, in today's society, companies are increasingly prioritizing safety management. They place significant emphasis on establishing and enhancing safety culture while actively developing safety management systems. They are dedicated to promoting various safety management tools and methods to ensure the health and safety of their employees
The Value-adding Strategy of Memory Foundry Industry
No full textFor the past three decades, memory has become an indispensable and important part of integrated circuits for humans. From Dynamic Random Access Memory (DRAM) to Toshiba's release of the NAND Flash architecture in 1989, this memory access structure is similar to a hard disk drive (HDD). Major manufacturers from the US, Japan, and Korea have invested heavily in research and development to production facilities, preparing to share a large piece of the pie.With the booming development of emerging technologies such as the Internet of Things (IoT), artificial intelligence (AI), and big data, the growing demand for memory will continue to drive the expansion of the NAND Flash market, a trend that will continue for decades to come.
Although the memory industry continues to progress, standardization within the industry has made it challenging for contract manufacturers to differentiate themselves. Therefore, this study applies qualitative research to analyze the strategies implemented by the case company. Using SWOT analysis and Porter's Five Forces analysis, the study conducts a strategic analysis and provides recommendations to help the company achieve success in the contract manufacturing market
Unveiling the Potential of Self-Supervised Learning for Cryo-EM Image Denoising
No full textThe purpose of this study is to investigate the application of self-supervised methods for denoising protein images. Cryo-electron microscopy (Cryo-EM) is one of the most important new techniques in structural biology research, and in recent years, Cryo-EM has successfully revealed protein structures at the atomic scale. However, due to limitations in instruments and the proteins themselves, the images obtained often contain high levels of noise, posing a significant challenge for reconstructing the three-dimensional structure of proteins. Therefore, image denoising plays a crucial role in this process. In comparison to traditional denoising methods such as wavelet, total variation, BM3D, and early neural network approaches that require either clean images or pairs of noisy images for training, we utilize four newly proposed self-supervised learning frameworks from the literature: Noise2Void, Self2Self, Noise2Same, and Neighbor2Neighbor. These methods only require noisy Cryo-EM images during training, and we investigate the effects of adjusting these methods and their hyperparameters on denoising performance. The results of the study demonstrate that our approach can successfully denoise Cryo-EM images without the need for knowing the noise level or clean images or paired noisy images. Moreover, our results are comparable to or even surpass traditional methods. Finally, we hope to apply our method to real datasets and various Cryo-EM tasks in the future
Using TQM Methods to Analyze PCBA Manufactory Key Resistance of Digital Transformation
No full textDigital transformation of SME is critical in today's competitive business environment. The purpose of the study was to success or failure of digital transformation, how to engage in digital transformation with the lowest cost and risk. In order to provide valuable advice and guidance for SME when engaging in digital transformation.
The research method includes interviewing the person in charge, team leader and operators of GHOME and inviting leaders of different generations of group GHOME to summarize and analyze through diverse analysis methods. We discuss the possible problems and concerns from the two aspects of the person in charge of the enterprise and the employees. Using the fishbone diagram and 5W analysis method to find the root cause of the problem, and find a solution from the successful experience of GHOME.
The results of the study show that the key factor for the success of digital transformation is not digital technology, but corporate culture. Before digital transformation, it is necessary to simplify, standardize and optimize the process to understand the real needs of the enterprise and try it out in the easiest and most cost-effective way to reduce the risk of failure. Management culture is also one of the key factors. The business philosophy of "People-Oriented" and "Happy working" of GHOME helps to overcome the problems in digital transformation. Therefore, process optimization is the current focus. After understanding the needs of process optimization, digitalization and optimization with digital technology will bring new opportunities to change the operating model, thereby achieving the success of digital transformation.
In summary, digital technology is only a tool to achieve goals, and solving problems is the real purpose. The real needs and management culture of the enterprise are the key factors for the success or failure of digital transformation. SME cannot plan a perfect operating model change in advance, but should let it happen. Focus on internal optimization of the enterprise and let digital transformation happen naturally. Therefore, the results of this study provide practical guidelines for SME to guide them to successfully improve their competitiveness, create more business opportunities, and achieve sustainable success in a highly competitive environment
Analyzing on the Impact of Circular Economy on Polyester Film Industry
No full textIn recent years, the Internet media has reported a large number of videos of Marine creatures being harmed by plastic products, which has aroused the uproar and attention of the society and public opinion. In addition, the practice of economic growth in the human society for centuries has caused ecological and resource depletion problems, leading to the crisis of human existence. Therefore, sustainable development has become a hot topic in the industry in recent years. Experts and scholars around the world have put forward different theories and solutions. Countries in the world have been actively amending laws, strictly enforce environmental protection laws and improve trade standards. From the theories proposed by experts and scholars, it is not difficult to find that the circular economy is the most feasible transformation of the plastification industry into a green industry, and it is also the direction of transformation for Taiwan's leading plastification group in the last few years. This study focuses on polyester film (abbreviated as PET film) as the research topic. As the product operates in a perfectly competitive market, Chinese supply chains have aggressively targeted the market with a low-price strategy, while Taiwanese manufacturers neglected strategies such as product differentiation, resulting in a decline in market share. From the oil crisis to climate change and environmental regulations, Taiwanese plastic manufacturers foresee future challenges and have decided to take action by revitalizing their products. They have been investing in research and development to transform polyester products into green materials. Currently, Taiwanese manufacturers hold a technological advantage. However, if Chinese supply chains overcome their technological barriers in the future, Taiwanese companies may once again face the threat of low-price competition. This study first introduces the circular economy theory, carbon rights and ban on single-use plastic, and then explains the impact of these laws on products. This research method will use SWOT and Business Model Canvas to analyze the polyester film industry, and then conduct in-depth interviews with relevant plasticizers and downstream processing companies, how companies respond to multiple pressures such as high costs, low purchasing power in the market, and environmental regulations. For the new green material - Recycled PET Film made of post-consumer recycled plastic (PSR), what are the challenges faced by Taiwanese manufacturers