To mitigate the inherent high flow resistance of conventional corrugated tubes, a novel design with alternating clockwise/counterclockwise corrugated segments separated by smooth sections is proposed. A 3D numerical model was developed to systematically evaluate the thermal-hydraulic performance of the novel tube against smooth and conventional corrugated tubes, with simulations conducted at Reynolds number (<i>Re</i>) = 9952–35,827. Results show both corrugated configurations enhanced heat transfer significantly relative to the smooth tube: the conventional tube had the highest Nusselt number (<i>Nu</i>) (1.76–1.79 times that of the smooth tube), while the novel tube achieved <i>Nu</i> = 1.61–1.65 times that of the smooth tube. Notably, the novel tube reduced flow resistance substantially—at <i>Re</i> = 35,827, its friction factor (<i>f</i>) was only 65.2% of the conventional tube’s. Parametric studies revealed that more corrugated segments improved heat transfer but increased pressure drop: the 72-12 configuration exhibited the best heat transfer, while the 72-2 configuration reduced <i>f</i> by 40.7%. The novel tube showed superior overall performance (Performance Evaluation Criterion (<i>PEC)</i> > 1.24 for all <i>Re</i>), as corrugated segments generated periodic vortices to disrupt the thermal boundary layer, while smooth segments enabled flow redevelopment and pressure recovery. This study provides valuable guidance for designing high-efficiency, low-resistance heat exchange elements.
Engineering machinery, tools, and implements, Technological innovations. Automation
In a world overshadowed by uncertainty, where technologically mediated connectedness can leave us feeling isolated and powerless, it is crucial to recognize that innovation seems our sole response.
In today's dynamic and highly competitive business environment, performance measurement and management systems play a crucial role. They help companies to be competitive. However, companies must properly set up approaches towards performance measurement, management, and all associated activities to take full advantage of these systems and ensure their sustainability. This can be a challenging task. Only some researchers discuss approaches toward comprehensive performance measurement and management. The authors have identified issues related to understanding, implementing, and using these systems. This article aims to fill this gap by providing a comprehensive view of performance measurement and management. It describes the performance measurement system, components, steps, measures, measurement areas, users, and information transfer. The performance management system has to consider the context of the entire organisation and embrace external and internal factors that influence its implementation, development and quality, as well as tools that make it more efficient and ensure its sustainability. The suggested framework is graphically illustrated. Finally, the meaningfulness, reality and possible usability in practice are verified through semi-structured interviews with managers of selected companies.
Artem Khoroshev, Ivan Vasyukov, Alexander Pavlenko
et al.
This paper considers the issues of the reduction in the computational complexity of the numerical problem and the requirements of the computer memory size when calculating the power of the eddy currents in a hydrogen fuel cell based on a proton exchange membrane. The study was performed on a model problem based on a geometric pattern of a hydrogen fuel cell of typical dimensions and characteristics operating at a nominal load in steady-state conditions. The power of the eddy currents was calculated using a numerical model based on a tetrahedral finite element mesh and a mathematical model of a quasi-stationary electromagnetic field in the classical formulation through the vector magnetic potential. The requirements for the minimum degree of the geometric model approximation by a finite element mesh to achieve mesh stability of the computational problem results were defined. The paper considers issues of finite element order selection, the method of ordering, and the solution of the systems of linear algebraic equations (SLAEs). It shows the techniques for determining the accuracy of the calculated SLAE solution obtained by the direct method, as well as the effectiveness of the low-rank approximation of the SLAE to reduce the computational complexity of the computational problem solution and reduce the requirements for the amount of computer memory needed, considering the reduced accuracy of the SLAE solutions.
Engineering machinery, tools, and implements, Technological innovations. Automation
This study uses a sample of pharmacists and pharmacy technicians (N = 240) who differ in skill, education, and income to replicate and extend past findings about socioeconomic disparities in the perceptions of automation. Specifically, this study applies the skills-biased technical change hypothesis, an economic theory that low-skill jobs are the most likely to be affected by increased automation (Acemoglu & Restrepo, 2019), to the mental models of pharmacy workers. We formalize the hypothesis that anxiety about automation leads to perceptions that jobs will change in the future and automation will increase. We also posit anxiety about overpayment related to these outcomes. Results largely support the skillsbiased hypothesis as a mental model shared by pharmacy workers regardless of position, with few effects for overpayment anxiety.
High-speed working units are very widely used in modern construction, in the destruction of durable materials and soils and more. When calculating the power and energy parameters of dynamic working units take into account changes in the nature of the interaction of the cutting element with the environment and the emergence and propagation of soil stresses from the action on the boundary of the array of the cutting element. This leads to the emergence of a stress-strain state in the soil mass, which has an oscillatory-wave character.
The nature of the stress-strain state is influenced by the state of the working environment and the speed of cutting (destruction) of the soil mass.
An unsolved problem in the dynamic destruction of soils is to take into account the kinematic features and technology of work with high-speed peripheral and front-end working units. The design parameters of these working units must take into account not only the dynamic parameters of the fracture process, but also the phenomenon of accumulation of fatigue deformations in the working environment.
Marie Luengen, Christopher Garrelfs, Kamil Adiloǧlu
et al.
Today, medical technology manufacturers enter the service market through the development of digital service innovations. In the field of audiology, these developments increasingly shift the service capacities from audiologists to manufacturers and technical systems. However, the technology-driven developments of manufacturers lack acceptance of hearing device users and undermine the important role of audiologists within the service provision. By following a user-centered design approach in order to deal with the technological and social challenges of disruptive services, we aim to develop service innovations on an integrated service platform in the field of tele-audiology. To ensure the acceptance of technology-driven service innovations among hearing device users and audiologists, we systematically integrated these actors in a participatory innovation process. With qualitative and quantitative data we identified several requirements and preferences for different service innovations in the field of tele-audiology. According to the preferences of the different actors, we proposed a service platform approach based on a connected hearing device in three pillars of application: 1) one-to-one (1:1) service innovations based on a remote fitting concept directly improve the availability of services offered by audiologists without being physically present. Based on this, 2) one-to-many (1:N) service innovations allow the use of the connected hearing device as an indirect data source for training a machine learning algorithm that empowers users through the automation of service processes. A centralized server system collects the data and performs the training of this algorithm. The optimized algorithm is provided to the connected hearing devices to perform automatic acoustic scene classification. This in turn allows optimization of the hearing devices within each acoustic scene. After the user-centered development of the different service innovations which are designed to converge on an integrated service platform, we experimentally evaluated the functionality and applicability of the system as well as the associated role models between the technical system, the hearing device users and audiologists. As a future outlook, we show potentials to use the connected hearing device for 3) cross-industry (N:M) service innovations in contexts outside the healthcare domain and give practical implications for the market launch of successful service innovations in the field of tele-audiology.
The debate surrounding fiscal decentralization is revived in times of threats to sustainable development whose effects are first experienced at the decentralized (local) level and are then transferred to the central level. The extent to which the management of public funds is decentralized is determined mainly by a country’s legal system, but also by economic, political and historical factors. A balanced relationship between central control and local autonomy in fiscal management can improve a country’s economic performance. This factor could play a key role in planning effective measures to minimize the adverse consequences of the economic recession caused by the Covid-19 pandemic. The aim of this study was to evaluate the degree of fiscal decentralization in European Union (EU) countries, to identify groups of EU Member States characterized by a similar degree of fiscal decentralization, and to describe their economic performance. The degree of fiscal decentralization was evaluated based on local government revenues as a percentage of the GDP in EU Member States. Agglomerative clustering and k-means clustering methods were used to identify groups of countries with similar degrees of fiscal decentralization. The economic performance of countries in each group was evaluated with the use of standard macroeconomic indicators. Three groups of countries with similar degrees of fiscal decentralization were identified. The most decentralized countries were Denmark, Sweden and Finland. These countries were characterized by the highest levels of economic growth. Eco-nomic growth was lowest in the countries that joined the EU after 2004. These countries were characterized by the relatively highest inflation rates and the lowest average household incomes.
The advent and rapid adoption of new technologies, such as machine learning and advanced robotics, have resurfaced concerns over technology eliminating jobs. Many now worry that more jobs are at risk than ever before. However, this debate all too often ignores the complexity of technology’s relationship to labour. Technological advancements throughout Canada’s history have helped to drive innovation and raise productivity, improve wealth and increase consumption, and give rise to entirely new industries and economic opportunities. As a result, in the long run technology has often helped to produce more jobs than it destroyed.
Wind energy conversion systems have become a key technology to harvest wind energy worldwide. In permanent magnet synchronous generator-based wind turbine systems, the rotor position is needed for variable speed control and it uses an encoder or a speed sensor. However, these sensors lead to some obstacles, such as additional weight and cost, increased noise, complexity and reliability issues. For these reasons, the development of new sensorless control methods has become critically important for wind turbine generators. This paper aims to develop a new sensorless and adaptive control method for a surface-mounted permanent magnet synchronous generator. The proposed method includes a new model reference adaptive system, which is used to estimate the rotor position and speed as an observer. Adaptive control is implemented in the pulse-width modulated current source converter. In the conventional model reference adaptive system, the proportional-integral controller is used in the adaptation mechanism. Moreover, the proportional-integral controller is generally tuned by the trial and error method, which is tedious and inaccurate. In contrast, the proposed method is based on model predictive control which eliminates the use of speed and position sensors and also improves the performance of model reference adaptive control systems. In this paper, the proposed predictive controller is modelled in MATLAB/SIMULINK and validated experimentally on a 6-kW wind turbine generator. Test results prove the effectiveness of the control strategy in terms of energy efficiency and dynamical adaptation to the wind turbine operational conditions. The experimental results also show that the control method has good dynamic response to parameter variations and external disturbances. Therefore, the developed technique will help increase the uptake of permanent magnet synchronous generators and model predictive control methods in the wind power industry.
Engineering machinery, tools, and implements, Technological innovations. Automation
The paper explores the patterns of business investment in research and development (R&D) using evidence from companies in South Africa, in comparison with indicators for a number of other countries. This study covers the period 2006–2016, the studied companies were grouped by the amount of R&D expenditures (BERD), the number of reports on research performance for the first and last years of monitoring. A typical characteristic of private sector R&D activities is the uneven distribution of resources in space and time. The major financial and other assets are concentrated within few large companies from a limited number of industries, while the majority of small and medium-sized enterprises invest in R&D projects only sporadically, for a period of no more than two consequential years. Firms that perform R&D for longer periods invest in R&D incrementally and remain more persistent than enterprises performing less R&D for shorter time periods. In view of the common nature of a number of patterns, these observations suggest different approaches to policies supporting R&D performance in the business sector not only in South Africa, but also in other countries.
In this paper, the problem of joint disparity and motion estimation from stereo image sequences is formulated in the spatiotemporal frequency domain, and a novel steerable filter-based approach is proposed. Our rationale behind coupling the two problems is that according to experimental evidence in the literature, the biological visual mechanisms for depth and motion are not independent of each other. Furthermore, our motivation to study the problem in the frequency domain and search for a filter-based solution is based on the fact that, according to early experimental studies, the biological visual mechanisms can be modelled based on frequency-domain or filter-based considerations, for both the perception of depth and the perception of motion. The proposed framework constitutes the first attempt to solve the joint estimation problem through a filter-based solution, based on frequency-domain considerations. Thus, the presented ideas provide a new direction of work and could be the basis for further developments. From an algorithmic point of view, we additionally extend state-of-the-art ideas from the disparity estimation literature to handle the joint disparity-motion estimation problem and formulate an algorithm that is evaluated through a number of experimental results. Comparisons with state-of-the-art-methods demonstrate the accuracy of the proposed approach.
Engineering machinery, tools, and implements, Technological innovations. Automation
Many organizations find themselves at the "front end of innovation", that is, they know they need to do something, but they are not quite sure what to do. Through our research, we have learned much more about the practice and implementation of innovation. For example, we have discovered that innovation is most successful if there is leadership support for a culture of innovation combined with systematic approaches to embed and reinforce innovative behaviours. This article outlines a case study of an organization in the financial services industry who began their innovation journey a number of years ago, and reports on the progress of a sustained and deliberate approach. This research highlights the relationship between an innovation cultural assessment model and its utilization as a framework to manage the implementation of activities to support the development of an innovation approach in a context specific scenario. A case study methodology was adopted that utilized an innovation culture model as a measurement tool. By actively observing the organization, including two cultural assessments over a 4-year period, the findings indicate that an innovation assessment model is useful as an approach to advance the innovation agenda in the organization. In this sense, the research findings are of interest to academics looking to conceptualize a broader implementation framework that is closely associated to the innovation measure associated with the organization. As well, practitioners looking to advance their innovation platforms will find the framework useful as they plan initiatives aimed at advancing their innovation agendas.
The aim of this research was to investigate the aroma profile and changes of individual volatiles during regular air (RA) and controlled atmosphere (CA) storage of ‘Conference’ pear during six months at 0 °C. Gas combinations used were: RA; 0.5 kPa O2 + 0.5 kPa CO2; 1.5 kPa O2 + 1.5 kPa CO2; 0.5 kPa O2 + 6.0 kPa CO2 and 3.0 kPa O2 + 6.0 kPa CO2. The main compounds found during ripening of ‘Conference’ pear were butyl acetate (34 %), ethyl acetate (16 %), hexyl acetate (12 %), ethanol (11 %) and methyl acetate (5 %). Fruits under RA produced the highest amounts of volatiles and intermediary emissions were measured under 1.5 kPa O2 + 1.5 kPa CO2 and 3.0 kPa O2 + 6.0 kPa CO2. The storage under 0.5 kPa O2 + 0.5 kPa CO2 and 0.5 kPa O2 + 6.0 kPa CO2 induced the strongest inhibition in total aroma production. Under CA, the emission of ethyl acetate was not significantly suppressed even under 0.5 kPa O2 + 6.0 kPa CO2. Ethanol release increased during shelf-life in fruits of all storage conditions. Butyl acetate was only slightly suppressed even under 0.5 kPa O2 + 6.0 kPa CO2 and hexyl acetate, was significantly reduced only under 0.5 kPa O2 combined with 6.0 kPa CO2.