We use a multiple case study approach to investigate “entrepreneurial leaps,” transition phases between dynamic states in which entrepreneurial action focused on reconfiguring key elements of the ...business model allows a firm to tap into new pools of resources through accessing and exploiting new market. Based on an analysis of 24 cases from three European countries, we derive a general process model of entrepreneurial leaps and identify four different patterns of how these transitions typically unfolds. The combination of dynamic states and entrepreneurial leaps can be used as a general framework for explaining nonlinear growth processes in firms.
Sharing the dynamic states among power system generators is crucial for wide-area monitoring, decentralized control, and protection of the prospective smart grid. However, this sharing process is ...subject to cyber–physical contingency conditions, which limits its accuracy. This paper proposes a framework that incorporates a cyber-layer with the power system to ensure accurate sharing of the generators’ dynamic states. The proposed framework utilizes a weighted average consensus mechanism within a blockchain environment. The consensus ensures that the communication links/data among generator buses are reliable in both directions and that any link/data failure is detected to guarantee the validity, and hence accuracy of the shared generators’ states. Moreover, a smart contract at each generator applies the proposed consensus mechanism and credits the validator generator bus that creates the next block in the states’ blockchain after achieving the consensus. Finally, the proposed framework is tested on the standard IEEE 3-generator 9-bus power system under data contingency conditions. The generators’ speed states are tested, while the other states can be verified in a similar manner. Simulation results show the ability of the proposed framework to ensure accurate sharing of the generators’ speed states and to detect possible cyber-attacks, compared to the case without using the proposed framework.
•We propose a blockchain-based framework including a weighted average consensus mechanism to ensure the peer-to-peer (P2P) accuracy of the generators’ measurements and estimated states in smart grids.•We propose to use smart contracts on the phasor measurement units (PMUs) to control the process of building and validating the blocks of the blockchain. The smart contracts will also credit the validator generator bus and add the next block in the generators’ estimated states blockchain.•The proposed weighted average consensus ensures that the communication links among generator buses (peers) are reliable, in both directions. That has an implicit/indirect effect on the estimated states by ensuring the PMUs’ data used in the state estimation is accurate which consequently ensures the accuracy of states.•Through simulations, we study the effect of both data spoofing/ data loss and communication link failure as cyber-attacks against the proposed framework.•The results of different communication data scenarios and cyber-attacks are illustrated to show the efficiency of the proposed method in ensuring states’ accuracy in the presence of disruptions or attacks.
The dynamic states of water in shrimp during drying process were investigated by low-field nuclear magnetic resonance and magnetic resonance imaging. With the extension of drying time, the transverse ...relaxation time of immobilized and free water significantly decreased, illustrating their mobility reduced. The signal per mass of immobilized water also decreased significantly, indicating its remarkable loss during drying process. Magnetic resonance imaging results revealed that the water signal intensity decreased from the external surface to inner regions of shrimp. Good correlations between the moisture content, hardness, chewiness, cohesiveness, L*, a* and nuclear magnetic resonance T2 parameters were observed by linear regression analysis.
Purpose This empirical paper investigates how entrepreneurial firms change their business models in the context of internationalization by identifying different forms of business model innovation ...(BMI) and exploring the interrelationship between BMI and internationalization. Design/methodology/approach Based on the dynamic states approach of entrepreneurship (Levie and Lichtenstein, 2010), this paper analyses primary and secondary data from nine European firms following a multiple case study approach. Findings This paper presents four patterns of radical change and eight types of incremental adaption with-in business models in the context of internationalization. We describe these BMI patterns and types, and we also show how they contribute to increasing involvement in international business activities and the internationalization-related triggers that might cause them. Originality/value This paper contributes to a better understanding of the BMI process in the course of internationalization. It also highlights the complex interrelationship between BMI and internationalization by building on a progressive theoretical approach.
•ASRCKF observation is proposed to estimate vehicle states.•The SP algorithm is put forward to calculate the μmax.•ASRCKF can improve the estimation accuracy, especially for vehicle sideslip ...angle.•Accurate μmax can always be obtained by the proposed algorithm.•Co-simulation and experiments are designed to verify the algorithm validation.
It is infeasible to measure vehicle dynamics states (VDS) directly without expensive measurement instruments, especially for the tire-road peak adhesion coefficient (μmax). However, four-wheel-independent-drive-electric-vehicle (4WIDEV) provides convenience for the observation of these dynamic states, because the rotation rate and torque of the in-wheel motor can be acquired directly. Vehicle nonlinear longitudinal-lateral dynamics, the single estimation method for all VDS and the time-varying measurement noise of sensors cause difficulties for the observation. Common the extended-Kalman-filter (EKF) is unsuitable to estimate VDS in strong nonlinear region. This paper propose a longitudinal-lateral cooperative estimation algorithm based on adaptive-square-root-cubature-Kalman-filter (ASRCKF) and partitioned similarity-principle (SP) to estimate the vehicle states and the tire-road peak adhesion coefficient sequentially for 4WIDEV. Firstly, a nonlinear 7-degree-of-freedom (7DOF) vehicle model and magic-formula (MF) tire model are built as the base of the successive estimation scheme. Then, recursive-least-squares (RLS) is adopted to estimate the tire longitudinal force. With the estimated tire longitudinal force, an ASRCKF which can be adjusted adaptively by the feedback dynamics states, is designed for the estimation of vehicle states. Next, the SP algorithm combined with the characteristic of longitudinal-lateral dynamics, which is benefit for μmax estimation when tire dynamics enters the nonlinear region, is proposed. Finally, experiment and simulation results show that excellent performance can be achieved with the proposed estimation method in varying driving conditions.
The dynamical organization of brain networks is essential to support human cognition and emotion for rapid adaption to ever-changing environment. As the core nodes of emotion-related brain circuitry, ...the basolateral amygdala (BLA) and centromedial amygdala (CMA) as two major amygdalar nuclei, are recognized to play distinct roles in affective functions and internal states, via their unique connections with cortical and subcortical structures in rodents. However, little is known how the dynamical organization of emotion-related brain circuitry reflects internal autonomic responses in humans. Using resting-state functional magnetic resonance imaging (fMRI) with K-means clustering approach in a total of 79 young healthy individuals (cohort 1: 42; cohort 2: 37), we identified two distinct states of BLA- and CMA-based intrinsic connectivity patterns, with one state (integration) showing generally stronger BLA- and CMA-based intrinsic connectivity with multiple brain networks, while the other (segregation) exhibiting weaker yet dissociable connectivity patterns. In an independent cohort 2 of fMRI data with concurrent recording of skin conductance, we replicated two similar dynamic states and further found higher skin conductance level in the integration than segregation state. Moreover, machine learning-based Elastic-net regression analyses revealed that time-varying BLA and CMA intrinsic connectivity with distinct network configurations yield higher predictive values for spontaneous fluctuations of skin conductance level in the integration than segregation state. Our findings highlight dynamic functional organization of emotion-related amygdala nuclei circuits and networks and its links to spontaneous autonomic arousal in humans.
One of the most effective methods for sand control is the chemical consolidation of sandstone structures. In this paper, the impacts of crude oil and brine in the static state and the impact of the ...flow rates of the fluids in the dynamic state have been assessed at the reservoir conditions. The analyses in this research were Young's modulus, compressive strength, porosity, and permeability which were done on core samples after and before fluid contact. Samples made with two different resins showed good resistance to crude oil in both states. No considerable change was seen in the analyses even at high crude oil injection rates in the dynamic state. Conversely, brine caused a noticeable change in the analyses in both states. In the presence of brine at the static state, Young's modulus and compressive strength respectively decreased by 37.5% and 34.5% for epoxy cores, whereas these parameters respectively reduced by 30% and 41% for furan cores. In brine presence at the dynamic state, compressive strength reduction was 10.28 MPa for furan and 6.28 MPa for epoxy samples and their compressive strength reached 16.75 MPa and 26.54 MPa respectively which are higher than the critical point to be known as weak sandstone core. Moreover, Young's modulus decrease values for furan and epoxy samples were respectively 0.37 GPa and 0.44 GPa. Therefore, brine had a more destructive effect on the mechanical characteristics of samples in the static state than the dynamic one for two resins. In addition, brine injection increased permeability by about 13.6% for furan and 34.8% for epoxy. Also, porosity raised by about 21.8% for furan, and 19% for epoxy by brine injection. The results showed that the chemical sand consolidation weakens in the face of brine production along with crude oil which can lead to increasing cost of oil production and treating wellbore again.
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•At static state, crude oil had no major impact on all analyses.•Crude oil injection rate only increased 2 % k, and 1 % φ, however, it had no effect on CS and E at dynamic state.•Static brine has more destructive effects than dynamic brine on CS and E for two resins.•At high rate, the impact of the brine injection was more effective on CS reduction of furan samples than of epoxy samples.•k and φ of the samples significantly increased by increasing the brine injection rate for two resins.
The article presents the exhaust emission results from a diesel engine in dynamic states of engine operation in the driving tests: NEDC (New European Driving Cycle) and Malta test, developed at the ...Poznan University of Technology. The NEDC and Malta tests were carried out as simulations on the engine test bench mimicking the driving tests conditions. The test results of the emission of carbon monoxide, hydrocarbons and nitrogen oxides obtained in each of the tests were presented. The dynamic states have been classified de-pending on the time derivative value of the torque and engine rotational speed. Both the positive and negative as well as zero time deriv-ative values of torque and rotational speed were considered. Therefore, overall six types of dynamic states were analyzed. A high sensi-tivity of exhaust emission to various types of dynamic states was found. The exhaust emission sensitivity to dynamic states in the Malta test was found to be higher than for the NEDC test, although these tests have similar properties (average rotational speed and average torque). This is due to the fact that the NEDC test is created on the basis of the similarity of zero-dimensional characteristics of the cars speed characteristic, whereas the Malta test was designed in accordance with the principle of faithful representation in the time domain of the NEDC speed curve.
This study investigates the shift in dynamical states of the thermo-acoustic oscillations for the turbulent syngas combustor having a bluff body for the flame anchoring. In this paper, an analysis ...was conducted to look into the effects of three different syngas compositions on the variation of Reynolds number (
Re
) in the range of 2289 to 8009. The analysis involved simultaneous, unsteady pressure measurement and OH* chemiluminescence. The investigation reveals that as the controlled parameters vary, the system exhibits a sequence of dynamic states characterized by distinct nonlinear oscillations. This study aims to explore the infrequently observed transitions from low-frequency instability (LFI) to high-frequency instability (HFI) by examining various time-series data and post-processing techniques. Additionally, it aims to understand how these transitions ultimately lead to the emergence of combustion noise as a result of a change in Reynolds number. To ascertain the characteristics of thermo-acoustic oscillations under investigation, a comprehensive analysis is conducted utilizing nonlinear time-series analysis techniques like phase portrait and recurrence plots. The investigation of flame behavior in response to changes in Reynolds number has been conducted using time-resolved OH* chemiluminescence. The results obtained from this study reveal distinct flame behavior patterns. The combustion instability of syngas at HFI is driven by flame modulated by small-scale structures and its anchoring in the shear layer of the bluff-body whereas the LFI is due to larger flame modulations near the wall of the combustion chamber. In addition, the recurrence analysis method is employed to monitor the progression of the dynamical states to understand the nature of the dynamical states. Such analysis will ultimately contribute to the establishment of a stable or nearly stable combustion system.
Convergent evidence has suggested atypical relationships between brain structure and function in major psychiatric disorders, yet how the abnormal patterns coincide and/or differ across different ...disorders remains largely unknown. Here, we aim to investigate the common and/or unique dynamic structure-function coupling patterns across major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SZ).
We quantified the dynamic structure-function coupling in 452 patients with psychiatric disorders (MDD/BD/SZ = 166/168/118) and 205 unaffected controls at three distinct brain network levels, such as global, meso-, and local levels. We also correlated dynamic structure-function coupling with the topological features of functional networks to examine how the structure-function relationship facilitates brain information communication over time.
The dynamic structure-function coupling is preserved for the three disorders at the global network level. Similar abnormalities in the rich-club organization are found in two distinct functional configuration states at the meso-level and are associated with the disease severity of MDD, BD, and SZ. At the local level, shared and unique alterations are observed in the brain regions involving the visual, cognitive control, and default mode networks. In addition, the relationships between structure-function coupling and the topological features of functional networks are altered in a manner indicative of state specificity.
These findings suggest both transdiagnostic and illness-specific alterations in the dynamic structure-function relationship of large-scale brain networks across MDD, BD, and SZ, providing new insights and potential biomarkers into the neurodevelopmental basis underlying the behavioral and cognitive deficits observed in these disorders.
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