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This article addresses four different variants of the well-known Tool Switching Problem (ToSP). For each variant, we discuss its complexity and propose a mathematical formulation. Motivated by a real-world application in the color printing industry, the third and fourth variants introduce a novel requirement into ToSP: the tool order constraint. Under this requirement, during the processing of each job, the selected tools must be sorted along the slot sequence in the machine, and the machine will use them for processing the job applying the tools in that order. We show that the new problem variants are NP -hard even when the job sequence is given as part of the input and the setup times are binary. We solve them by using dedicated arc flow models. We evaluate the effectiveness of the models on several instances that were generated with the aim of covering different scenarios of interest. Our code finds proven optimal solutions for most of the instances with up to 30 jobs, 60 tools and 10 slots. [ABSTRACT FROM AUTHOR]

Powder bed fusion—laser beam (PBF-LB), a prevalent and rapidly advancing additive manufacturing (AM) technology nowadays, serves the industry by producing thin, complex, and lightweight components for various sectors, including healthcare, automotive, defence, and aerospace. However, this technology encounters challenges related to the construction of critical parts and the high overall process costs. Equally significant is the role of support structures in metal laser powder bed fusion (PBF-LB/M). The absence of supports can lead to defective and collapsed parts, while the incorrect selection of a support type or the addition of unnecessary supports results in increased material usage and additional post-processing efforts. Therefore, there is a pressing need for advanced software capable of generating appropriate support structures and predicting the thermomechanical behaviour of a part under PBF-LB/M printing conditions. Such software would be beneficial for the industry to avoid printing defects caused by high thermal stresses, minimise material usage, reduce printing time, and ensure high-quality prints. In this study, we introduce a web-based support generation and optimisation platform for PBF-LB/M. Through this platform, among other features, users can import three-dimensional (3D) parts and generate block-type support structures with diamond perforations based on the PySLM library, all within a user-friendly web environment. The first release of the platform (v0.6) is fully interactive and accessible online at no cost. [ABSTRACT FROM AUTHOR]

This paper presents the rapid and dynamic transition of the Bulgarian book from the Late Middle Ages to Modernity between 1806 and 1878. Special attention is paid to the work of Hristo G. Danov—one of the founders of modern Bulgarian book publishing, book printing and book trade. His business spread within the vast geographical area of Central and Eastern Europe, between the Austrian and Ottoman Empires' capitals. The research focuses on topics such as transnational book communication, book travel from place to place and multilingual printing book context. It presents how the printed book as a new means of text dissemination was used during the Bulgarian Revival—the difficult process that had to balance with many geopolitical, religious and social factors, as well as characteristics of daily life in the Ottoman Empire. Besides the Bulgarian national context, this paper refers to the organization of book publishing in geographical and economic aspects, the pursuit of an intellectual project through an active search for authors, texts and ideas, and the relation between book publishing and politics. [ABSTRACT FROM AUTHOR]

BackgroundChronic n-Hexane poisoning is prevalent among workers in small and micro printing industries in China. Despite this, there is limited research on occupational health risk assessment in these sectors. Conducting comprehensive risk assessments at key positions and proposing effective countermeasures are essential.MethodsData were collected from 84 key positions across 32 small and micro-sized printing enterprises. Air samples were tested for n-Hexane exposure levels in accordance with Chinese standards. Five risk assessment models were employed: COSHH, EPA, MOM, ICMM, and Technical Guide GBZ/T 289-2017 of China. The consistency of results across these models was analyzed.ResultsWorkers in 84 job positions were categorized into four exposure groups, with exposure to n-Hexane for 8–10 h daily, 5–6 days weekly. Most positions operated with low automation levels (96.9% in printing, 5.9% in oil blending, and 42.9% in pasting), while others were manual. Localized ventilation rates were notably low in oil blending (23.5%), cleaning (14.3%), and pasting (9.5%) groups. n-Hexane concentrations exceeded Chinese occupational limits in 15.6% of printing, 17.7% of oil blending, and 21.4% of cleaning groups. Risk assessment models identified over 60% of work groups as high risk. Significant differences (p

Contrary to its dictionary definition, 'heart failure' doesn't mean the heart has stopped beating. Heart failure--HF, for short--develops when the heart can't pump enough blood for the body's needs. Also [...]

The manufacturing sector is an important part of the U.S. economy. Yet, looking at the manufacturing sector as a whole can mask the varied performance of the many diverse industries [...]

Information and Communication Technologies (ICTs) have forced long-established businesses to adapt to innovations. Most changes have emerged from the digitization of products and services. In the United States (U.S.), the printing industry has faced enormous challenges ranging from shifting markets to declining sales. As a result, several jobs have become redundant. We argue that the digitization phenomenon can be ascribed to the Schumpeterian paradigm of creative destruction. This study measures digitization’s impact on employment and wages in the U.S. printing industry from 2002 to 2021. We conduct an exploratory statistical analysis to verify whether the printing industry has experienced any impact on employment and wages compared to the American national trend. We draw on the United States Bureau of Labor Statistics Occupational Employment and Wage Statistics (OEWS) Survey to analyze historical employment and wage figures between 2002 and 2021. Empirical evidence suggests that the U.S. printing industry has experienced a substantial reduction in its workforce, with wages also suffering lower rises than the rest of the economy. The importance of this article rests in its contribution to the analysis of the economics of innovation by considering the impact of new technologies on employment in traditional activities, while other works concentrate mainly on new sectors.

The purpose of the study is to determine the peculiarities of the use of information and communication technologies in the printing industry; to substantiate the feasibility of technological transformation in terms of the prospects for economic development of the selected industry. Processing of primary data to provide the user with the necessary information is the main task of using information technology in the printing industry. Three main blocks – knowledge base, decision-making and intellectual interface – make up the structure of an intelligent printing system. In terms of decision-making, an intelligent printing system is defined as an information and computer system with artificial intelligence that solves problems without human intervention, in contrast to an intelligent system where the operator is involved in the decision-making process. The following types of intelligent systems are identified: intelligent information systems, expert printing systems, computational and logical systems, hybrid intelligent systems, reflex intelligent systems. It is noted that taking into account market trends, adapting to the environment and quickly adjusting their development strategy to occupy their niche in the market is important for the successful functioning of publishing and printing companies. According to the authors, this is possible based on using ICT in printing. Integrating modern technologies into the printing industry can positively influence efficiency and competitiveness. Adopting digital technologies will allow printing companies to be more flexible and respond quickly to changing market conditions, which is important for its development. In conclusion, it can be said that information and communication technologies have a great potential for the transformation of the printing industry in Ukraine. Companies will be able to automate and optimise production processes, reduce costs and improve product quality through the introduction of modern technologies. In addition, by introducing new print formats and creating specialised products for the digital market, the development of information technology will expand the range of services. According to the authors, this approach will help Ukrainian companies to compete internationally and take their products to new markets, helping to develop the whole industry. In addition, there will be a stimulus for innovation and the development of new services, which in turn will contribute to the growth of the industry as a whole.