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This paper analyzes the long-term effects of potentially avoidable cesarean sections on children’s health. Using Finnish administrative data, we document that physicians perform more unplanned C-sections during their regular working hours on days that precede a weekend or public holiday and use this exogenous variation as an instrument for C-sections. We supplement our instrumental variables resul

We investigate local convergence of identical DC/AC converters interconnected via identical resistive and inductive lines towards a synchronous equilibrium manifold. We exploit the symmetry of the resulting vector field and develop a Lyapunov-based framework, in which we measure the distance of the solutions of the nonlinear power system model to the equilibrium manifold by analyzing the evolution

This chapter examines changes to safe third country law and practice from 2010 to 2020 focusing on Europe, Australia, North, and South America. These developments have received little academic attention, particularly from a comparative perspective. We argue that in all four regions there has been a significant weakening of protection standards in the safe third country context, with the thresholds

Smart cyber-physical systems (S-CPSs) are complex engineered systems empowered by cyber-physical computing and equipped with the capability of reasoning, learning, adapting, and evolving. As an outcome of data-driven dynamic computing, reasoning capabilities, and the run-time obtained own knowledge, nonlinear and emergent behavior of S-CPSs whilst in operation is an open issue, not experienced in

The world is currently facing an ecological crisis of unprecedented scale and urgency and, as the building sector is a significant contributor to the current state, it must look towards radical change to achieve a sustainable practice. The most destructive environmental impact is found in material extraction, processing and discharge. This paper presents an alternative to industrially mined and sy

The presented work is focused on the development of a comprehensive thermo-mechanical model for predicting the temperature rise in thermoplastic polymer spur gears with any desired profile geometry while running. The specific constitutional behavior of thermoplastics influences the gear-meshing pattern, which can deviate substantially from ideal gear meshing, as typically exhibited by metal gears

The temperature increase that occurs during running of a polymer gear pair can be divided into two components: the nominal and flash temperatures. The latter denotes the short-term temperature increase that takes place during a gear meshing cycle. A thorough analysis of the flash temperature yields an insight into the heat dissipation process, which also determines the nominal temperature increase

Aircraft maintenance and repair organizations (MROs) have to be competitive and attractive for both existing and new customers. The aircraft ground time at MROs should be as short as possible and cost effective without reducing the quality of the work. Process optimization in MROs requires the continuous improvement of processes and the elimination of non-value-added activities during maintenance

This paper presents a new accelerated testing procedure for plastic gears that is based on several different levels of testing. The iterative testing procedure fulfils requests from the product development process. The following criteria are considered for testing: reduced number of tests, shorter test time and reliable results for different applications. The proposed method was applied over the f

The parameters necessary for the reliable design of PEEK gears were determined. The effect of a steel gear's surface on the polymer gear's wear was investigated. Values for the wear coefficient of a steel/PEEK gear pair in dry and lubricated conditions are proposed. Testing showed that, on average, grease lubrication extends the lifespan of PEEK gears by a factor of 1.23, while the additional trea

Supplier relationships in the automotive industry have changed fundamentally in recent decades owing to trends such as less verticalintegration, global sourcing, simultaneous engineering, and theInternet. Suppliers have become much more important in terms ofboth production and development. The ability to manage engineeringchanges (EC) efficiently and reliably reflects the capability of thewhole su

Conventionally, a technical system is defined in the design phase and considers all important requirements and aspects. The expected operations and the circumstances of operations are to be known in advance. If these are known, then the designed system can even be validated before it is produced or launched on the market. Validation is typically based on predictive analyses or simulations. However

Beliefs, expectations and values are often assumed to drive decisions about climate change adaptation. We tested hypotheses based on this assumption using survey responses from 508 European forest professionals in 10 countries. We used the survey results to identify communication needs and the decision strategies at play, and to develop guidelines on adequate communications about climate change adBeliefs, expectations and values are often assumed to drive decisions about climate change adaptation. We tested hypotheses based on this assumption using survey responses from 508 European forest professionals in 10 countries. We used the survey results to identify communication needs and the decision strategies at play, and to develop guidelines on adequate communications about climate change ad

The robust engineering seeks for design of products and processes insensitive to changes in the work environment and to the variation of the components. The robust process has built-in mechanisms to detect potential errors on time, to eliminate them and to initiate all the necessary measures to ensure the same error does not occur again. One-of-a-kind production is characterised by unique products

The paper presents an application of job process planning and scheduling into the production of turned parts. Both planning and scheduling are controlled by the genetic algorithm (GA) approach in order to achieve optimum plans. Genetic algorithms are one of the artificial intelligence methods. With GA we are searching in an iterative manner for possible schedules taking into account the limitation