Network controllability mediates the relationship between rigid structure and flexible dynamics

Precisely how the anatomical structure of the brain supports a wide range of complex functions remains a question of marked importance in both basic and clinical neuroscience. Progress has been hampered by the lack of theoretical frameworks explaining how a structural network of relatively rigid inter-areal connections can produce a diverse repertoire of functional neural dynamics. Here, we address this gap by positing that the brain’s structural network architecture determines the set of accessible functional connectivity patterns according to predictions of network control theory. In a large developmental cohort of 823 youths aged 8 to 23 years, we found that the flexibility of a brain region’s functional connectivity was positively correlated with the proportion of its structural links extending to different cognitive systems. Notably, this relationship was mediated by nodes’ boundary controllability, suggesting that a region’s strategic location on the boundaries of modules may underpin the capacity to integrate information across different cognitive processes. Broadly, our study provides a mechanistic framework that illustrates how temporal flexibility observed in functional networks may be mediated by the controllability of the underlying structural connectivity.

The Economics of Variable Renewable Energy and Electricity Storage

The transformation of the electricity sector is a central element of the transition to a decarbonized economy. Conventional generators powered by fossil fuels have to be replaced by variable renewable energy (VRE) sources in combination with electricity storage and other options for providing temporal flexibility. We discuss the market dynamics of increasing VRE penetration and its integration in the electricity system. We describe the merit-order effect (the decline of wholesale electricity prices as VRE penetration increases) and the cannibalization effect (the decline of VRE value as its penetration increases). We further review the role of electricity storage and other flexibility options for integrating variable renewables and how storage can contribute to mitigating the two mentioned effects. We also use a stylized open-source model to provide some graphical intuition on these issues. While relatively high shares of VRE are achievable with moderate amounts of electricity storage, the role of long-duration storage increases as the VRE share approaches 100%.

Do Saudi Arabian Leaders Exhibit Ambidextrous Leadership: A Qualitative Examination

The study identifies how subordinates of a multinational organization in Saudi Arabia perceive ambidextrous leadership’s explorative and exploitative factors. A qualitative design was adopted for the study. Data was collected from the employees’ comments about the leaders in a large multinational conglomorate’s organizational Electronic Social Networking (ESN) platform. The comments so collected were analyzed using Thematic Analysis (TA) to address the research objectives. The study results indicate that the leaders exhibited exploration, exploitation, and temporal flexibility styles signifying ambidextrous leadership. Ambidexterity is an aspect that is receiving increased research attention. Despite its widespread use in management science, ambidextrous leadership (AL), and individual level ambidexterity got initiated only in the current decade. The current study extends the literature about AL.

The Economic and Climate Value of Flexibility in Green Energy Markets

This paper examines how enhanced flexibility across space, time, and a regulatory dimension affects the economic costs and CO$$_2$$ 2 emissions of integrating large shares of intermittent renewable energy from wind and solar. We develop a numerical model which resolves hourly dispatch and investment choices among heterogeneous energy technologies and natural resources in interconnected wholesale electricity markets, cross-country trade (spatial flexibility), energy storage (temporal flexibility), and tradable green quotas (regulatory flexibility). Taking the model to the data for the case of Europe’s system of interconnected electricity markets, we find that the appropriate combination of flexibility can bring about substantial gains in economic efficiency, reduce costs (up to 13.8%) and lower CO$$_2$$ 2 emissions (up to 51.2%). Regulatory flexibility is necessary to realize most of the maximum possible benefits. We also find that gains from increased flexibility are unevenly distributed and that some countries incur welfare losses.

The nature of paid work in the retirement years

Ever more people are in paid work following the age of state pension availability, and yet the experience of working in this phase of the late career has been little studied. We interviewed a purposive sample of 25 Swedish people in their mid- to late sixties and early seventies, many of whom were or had recently been working while claiming an old-age pension. The data were analysed with constant comparative analysis in which we described and refined categories through the writing of analytic memos and diagramming. We observed that paid work took place within a particular material, normative and emotional landscape: a stable and secure pension income decommodifying these workers from the labour market, a social norm of a retired lifestyle and a looming sense of contraction of the future. This landscape made paid work in these years distinctive: characterised by immediate intrinsic rewards and processes of containing and reaffirming commitments to jobs. The oldest workers were able to craft assertively the temporal flexibility of their jobs in order to protect the autonomy and freedom that retirement represented and retain favoured job characteristics. Employed on short-term (hourly) contracts or self-employed, participants continually reassessed their decision to work. Participation in paid work in the retirement years is a distinctive second stage in the late career which blends the second and third ages.

Analyzing the Charging Flexibility Potential of Different Electric Vehicle Fleets Using Real-World Charging Data

A successful transformation of the energy and transportation sector is one of the main targets for our society today. Battery electric vehicles can play a key role in future renewable-based energy supply systems because of their ability to store electrical power. Additionally, they provide significant charging flexibility due to the long parking durations. In this paper, we provide insights into the temporal and power-specific flexibility behavior of three different vehicle fleets. These fleets are pool vehicles of office employees, a public authority, and a logistics company. Several parameters, such as the average charging power per charging event or the average plug-in duration per charging event, are discussed. Additionally, we investigate different charging rates and their impact on the temporal flexibility of the charging events. The data analysis shows that the logistics site has the most homogeneous charging profile as well as high charging flexibility, in contrast to the office and public agency site. The results are of significant importance for future applications in the field of smart charging and ancillary services provision.

Flexibility in the Gig Economy: Managing Time on Three Online Piecework Platforms

Gig economy platforms seem to provide extreme temporal flexibility to workers, giving them full control over how to spend each hour and minute of the day. What constraints do workers face when attempting to exercise this flexibility? We use 30 worker interviews and other data to compare three online piecework platforms with differing histories and worker demographics: Mechanical Turk, MobileWorks, and CloudFactory. We find that structural constraints (availability of work and degree of worker dependence on the work), as well as cultural-cognitive constraints (procrastination and presenteeism), limit worker control over scheduling in practice. The severity of these constraints varies significantly between platforms, the formally freest platform presenting the greatest structural and cultural-cognitive constraints. We also find that workers have developed informal practices, tools, and communities to address these constraints. We conclude that focusing on outcomes rather than control is a more fruitful way to assess flexible working arrangements.

Optimal supply chains and power sector benefits of green hydrogen

Green hydrogen can help to decarbonize parts of the transportation sector, but its power sector interactions are not well understood so far. It may contribute to integrating variable renewable energy sources if production is sufficiently flexible in time. Using an open-source co-optimization model of the power sector and four options for supplying hydrogen at German filling stations, we find a trade-off between energy efficiency and temporal flexibility. For lower shares of renewables and hydrogen, more energy-efficient and less flexible small-scale on-site electrolysis is optimal. For higher shares of renewables and/or hydrogen, more flexible but less energy-efficient large-scale hydrogen supply chains gain importance, as they allow to temporally disentangle hydrogen production from demand via storage. Liquid hydrogen emerges as particularly beneficial, followed by liquid organic hydrogen carriers and gaseous hydrogen. Large-scale hydrogen supply chains can deliver substantial power sector benefits, mainly through reduced renewable curtailment. Energy modelers and system planners should consider the distinct flexibility characteristics of hydrogen supply chains in more detail when assessing the role of green hydrogen in future energy transition scenarios. We also propose two alternative cost and emission metrics which could be useful in future analyses.