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The overall aim of this research work was the improvement of the failure behavior of printed circuit boards (PCBs). In order to describe the mechanical behavior of PCBs under cyclic thermal loads, thin copper layers were characterized. The mechanical properties of these copper layers were determined in cyclic four-point bend tests and in cyclic tensile-compression tests, as their behavior under changing tensile and compression loads needed to be evaluated.

Specimens for the four-point bend tests were manufactured by bonding 18-μm-thick copper layers on both sides of 10-mm-thick silicone plates. The silicone was characterized in tensile, shear and blow-up tests to provide input data for a hyperelastic material model. Specimens for the cyclic tensile-compression tests were produced in a compression molding process. Four layers of glass fiber-reinforced epoxy resin (thickness 90 μm) and five layers of copper (thickness 60 μm) were applied.

The results showed that, due to the hyperelastic material behavior of silicone, the four-point bend tests were applicable only for small strains, while the cyclic tensile-compression tests could successfully be applied to characterize thin copper foils in tensile and compression up to 1 percent strain.

Thin copper layers (foils) could be characterized successfully under cyclic tensile and compression loads.

The role of public procurement as an instrument to stimulate innovation has been increasingly emphasized by European policymakers. This perspective raises demand for the understanding of public procurement as an activity taking place in a variety of different procurement contexts and as an act of innovation. Accordingly, this paper proposes a taxonomy of public procurement and innovation, combining interactive learning and evolutionary perspectives on innovation processes to account for the broad range of different ‘interaction environments’ or ‘resource interfaces’ in which government or public sector organizations may act as lead users of innovations. On this basis, the taxonomy draws practical policy implications for the design of programmes and initiatives for the public procurement of innovations.

Aluminum is an exchange commodity. But physical trading of this metal in most cases does not occur on the stock exchange, since more than 90% of aluminum sales with physical delivery occur under direct contracts between producers and buyers of the metal (over-the-counter market). Aluminum as an exchange commodity has standardized consumer properties, namely: the goods are interchangeable, easily transported and stored, and can be divided into batches. That is why upstream products are traded on commodity exchanges, not semifinished products or finished products. When commodity exchanges were first created, they served as a place for concluding physical contracts for the supply of such exchange-traded goods, but with the increase in trading volumes and the development of financial instruments, the role of exchanges has changed. Today, futures contracts for raw materials are traded on them – financial instruments that almost never entail a real physical supply (at the same time, this possibility is not excluded). As a result of the bidding, a price is set that serves as a guideline for producers and consumers around the world.

The purpose of this paper is to investigate opportunities to move benchmarking studies toward a strategic level. The authors benchmarked how service prices are defined based on the value added for the customer.

A multi-case research investigated how manufacturers can increase their service revenues; how corporate reputation can be analyzed to enhance financial and market performance; how customer satisfaction and price acceptance are related; and how benchmark studies can move to a more strategic level based on a conjoint analysis of value and price.

Price’s benchmarking studies must combine the customers’ value demands; the customer expectations associated to each value demand; the competitor prices; and the revenue alternatives that a supplier can explore (e.g. sale of new goods, services for new goods, services for non-new goods, and repair parts). The combination of these elements reveals several opportunities for revenue generation. This combination may also help to explain the existence of different prices for similar goods and services. The authors referred to this as a flexible pricing policy. Flexible pricing may help manufacturers maximize revenues, and win and maintain customers.

The following research questions are suggested for future studies: What other elements should be considered in strategic benchmarking studies? What other elements can influence a flexible pricing policy for goods, spare parts, and services? In what contexts can a flexible pricing policy be applied? How should flexible pricing practices be benchmarked?

A strategic benchmarking study must first identify the customers’ value demands. It is then necessary to analyze customer expectations associated to each value demand. As shown, customers may have different expectations for the same product or service. Similar expectations must be grouped together in order to allow a well-structured benchmark.

The authors’ findings suggest interesting points to be observed by the manufacturers who supply integrated solutions with a long life cycle.

Bioenergy remains the largest branch of renewable energy, and microalgae are a promising object of research among other types of biomasses whose scale for energy purposes is increasing. On the other hand, the growth of global energy production and urbanization, which results in high rates of municipal waste and wastewater generation, requires the development of integrated technologies that allow waste to be disposed of as fully as possible. Sustainable investments in the production of energy by various technologies are one of the methods to solve this complex problem. In this chapter, we study the methods of microalgae utilization of nutrients from wastewater and by-product liquid waste of sustainable investments from microalgae by hydrothermal liquefaction (HTL) technology. Wastewater has a complex composition, and the treatment of nitrogen and phosphorus and other biogenic elements, as well as heavy metals, using biological objects is optimal and cost-effective. Also the water phase after HTL is a by-product that has limited energy value. Biofuel investments have higher growth rates and at the same time do not compete with the investments in fossil fuels. Biofuel investments' cost of seaweed fuel can be reduced through high-value-added related products, such as food and feed additives, and pharmaceutical and cosmetic products.

In scientific works on forecasting price volatility (of which the overwhelming majority, in comparison with works on price forecasting) for energy products: crude oil, natural gas, fuel oil, the authors compared the effectiveness of forecasting models of generalized autoregressive heteroscedasticity (Generalized Autoregressive Conditional Heteroscedastic model, GARCH) with regression of support vectors for futures contracts. GARCH models are a standard tool used in the literature on volatility, and the vector machine nonlinear regression model is one of the machine learning methods that has been gaining huge popularity in recent years. The authors have shown that the accuracy of volatility forecasts for energy and aluminum prices significantly depends on the volatility proxy used. The model with correctly defined parameters can lead to fewer prediction errors than GARCH models when the square of the daily yield is used as an indicator of volatility in the evaluation. In addition, it is difficult to choose the best model among GARCH models, but forecasts based on asymmetric GARCH models are often the most accurate. The work is based on a model with a representative investor who solves the problem of optimizing utility in a two-period model. The key assumption of the model is the homogeneity of energy and aluminum investor preferences, that is, preferences do not change over time. There are also works with an attempt to solve this problem in a continuous state space. A completely new theory has been put forward that allows predicting the movement of the underlying asset without using historical data, so this topic is very relevant.

The military operation of the Russian Federation on the territory of Ukraine exerted additional pressure on prices on the aluminum market since aluminum supplied by Russia accounts for about 10% of the total volume of US imports. It is known that Russia has become the largest aluminum producer after China, and now there is also an increase in aluminum production. Since electricity prices remain relatively low in Russia, especially in energy-surplus Siberia, the increase in output along with the increase in metal prices is a positive factor, since 70% of the primary aluminum produced is exported and only less than a third is consumed domestically. At the same time, high aluminum prices may constrain the expansion of domestic consumption of the metal and may force manufacturers to look for a cheaper alternative. In general, the increase in aluminum prices coincides with the general “supercycle” of raw materials in the last year and a half, and there is a chance to stabilize aluminum prices at current high levels, which will be facilitated, among other things, by new metallurgical projects in Russia. At the same time, it is worth noting that limited metal supplies will haunt the industry for most of 2022, and some experts predict that it may take up to five years to solve the problems.

The purpose of this paper is to analyse, in a finite element simulation, the failure of a multilayer printed circuit board (PCB), exposed to an impact load, to better evaluate the reliability and lifetime. Thereby the focus was set on failures in the outermost epoxy layer.

The fracture behaviour of the affected material was characterized. The parameters of a cohesive zone law were determined by performing a double cantilever beam test and a corresponding simulation. The cohesive zone law was used in an enriched finite element local simulation model to predict the crack initiation and crack propagation. Using the determined location of the initial crack, the energy release rate at the crack tip was calculated, allowing an evaluation of the local loading situation.

A good concurrence between the simulated and the experimentally observed failure pattern was observed. Calculating the energy release rate of two example PCBs, the significant influence of the chosen type on the local failure behaviour was proven.

The work presented in this paper allows for the simulation and evaluation of failure in the outermost epoxy layers of printed circuit boards due to impact loads.

Global warming exacerbates sea level rise and extreme weather events that cause severe flooding, resulting in lost productivity and property damage. To reduce the impact of flooding, residents are avoiding purchasing homes in high-risk areas. There are numerous studies on the relationship between flood hazards and housing prices in developed countries, but few in developing countries. Therefore, this study aims to investigate the relationship between flood hazards and housing prices in Hat Yai, Songkhla, Thailand.

This study uses spatial-lag, spatial error and spatial autoregressive lag and error (SARAR) models to analyze the effect of flood risk on property prices. The main analysis examines the degree of flood risk and housing rental prices from our survey of 380 residences. To test the robustness of the results, the authors examine a different data set of the same samples by using the official property valuation from the Ministry of Finance and the flood risk estimated by the Southern Natural Disaster Research Center.

The SARAR model was chosen for this study because of the occurrence of spatial dependence in both dependent variable and the error term. The authors find that flood risk has a negative impact on property prices in Hat Yai, which is consistent with both models.

This study is one of the first to use spatial econometrics to analyze the impact of flood risk on property prices in Thailand. The results of this study are valuable to policymakers for benefit assessment in cost–benefit analysis of flood risk avoidance or reduction strategies and to the insurance market for pricing flood risk insurance.