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Effects of supply chain innovation and application policy on firm performance:evidence from China
Get PDFTo accelerate the innovation and application of supply chains, China issued the Supply Chain Innovation and Application (SCIA) policy in 2017. We empirically explored the net and dynamic effects of SCIA policy on firm profitability by applying difference in differences and propensity score matching methods. Results show that SCIA policy significantly promoted firm profitability and it had a dynamic and time-lag effect. For firms in developed regions, SCIA played a more obvious role in promoting firm profitability. Notably, SCIA policy has been more supportive for non-state firms’ profitability than state ones. The results enrich the understanding about the net and dynamic effects of supply chain innovation policies on firm profitability. Accordingly, they not only guide firms on how to perform supply chain innovation and application activities under the new policy, but also provide insights to improve the existing SICA policy.</p
Harborfront Anomaly Detection
Get PDFCreating high-quality datasets for the task of video anomaly detection is challeng-ing due to a subjective anomaly definition and the rarity of anomalies, which oustthe possibility of obtaining statistically significant data. This results in datasetswhere anomalies are placed in a single category, and are often considered less rel-evant from a security standpoint. Instead, we propose to create video anomalydatasets based on a framework utilizing object annotations to ease the annotationprocess and allow users to decide on the anomaly definition. Furthermore, thisallows for a fine-grained evaluation w.r.t. anomaly types, which represents a nov-elty in the area of video anomaly detection. The framework is demonstrated usingthe existing thermal long-term drift (LTD) dataset, identifying and evaluatingfive different types of anomalies (appearance, motion, localization, density, andtampering) on six test sets. State-of-the-art anomaly detection methods are evalu-ated and found to underperform on the thermal anomaly detection dataset, whichemphasizes a need for an adjustable anomaly definition in order to produce bet-ter anomaly datasets and models that generalize towards practical use. We sharethe code of the proposed framework to extract anomaly types along with objectannotations for the LTD dataset at https://github.com/jagob/harborfront-vad
Passivity-Based Controller Design of LCL-Filtered Selective-Harmonic Resistive-Active Power Filter
No full textPassive property of grid-tied converter’s output admittance is widely recognized as favorable to stability. However, the admittance of active power filter (APF) is dependent on the nonlinear load (NLL) applied. Thus, the passivity-based design of APF is also dependent on the specific NLL. To deal with this problem, this article suggests replacing APF with resistive active power filter (RAPF) whose admittance is unrelated to NLL. Virtual impedance or virtual admittance control schemes are examined in this article. It turns out that none of them is stable. Then, a new control scheme is proposed which emulates desired virtual immittance at selected frequencies. Passivity-based controller design for proposed RAPF is then formulated. Meanwhile, a simpler calculation method for compensation angle of resonant controller is proposed. The effectiveness and correctness of the proposed control scheme is finally verified by experiments.<br/
Risk of psychiatric neurodevelopmental disorders after meningitis in childhood: a nationwide, population-based cohort study
No full textBackgroundFew studies have investigated the risk of psychiatric neurodevelopmental disorders (PNDD) after childhood meningitis.MethodsNationwide population-based cohort study (Denmark, 1995–2021) of children with positive cerebrospinal fluid for bacteria or enterovirus, stratified on age as young infants (0 to <90 days, n = 637) or older children (≥90 days to <17 years, n = 1,218). We constructed a comparison cohort from the general population (n = 18,550), and cohorts of siblings of participants. As risk estimates of PNDD we calculated age- and sex-adjusted hazard ratios (aHRs) with 95% confidence intervals (95%CI).ResultsChildren with bacterial meningitis had increased risks of PNDD, especially learning and intellectual developmental disorders (young infants: aHR 4.2, 95%CI: 2.4–7.1; older children: aHR 1.5, 95%CI: 1.0–2.3), attention deficit disorder (ADHD) (young infants: aHR 2.8, 95%CI: 1.5–5.2; older children: 1.4, 95%CI: 0.9–2.2) and redemption of ADHD medication (young infants: aHR 2.2, 95%CI: 1.0–4.7; older children: 1.5, 95%CI: 1.0–2.3). Young infants with bacterial meningitis additionally had increased risks of autism spectrum disorders (aHR 1.9, 95%CI: 0.9–4.1) and behavioural and emotional disorders (aHR 2.0, 95%CI: 1.0–3.9). In young infants, the excess risk of PNDD was especially observed in premature children. Siblings of older children with bacterial meningitis also had increased risks of PNDD. Children with enteroviral meningitis at any age did not have increased risks of PNDD or redemption of ADHD medication.ConclusionsBacterial meningitis in childhood is associated with subsequent diagnosis of PNDD, while enteroviral meningitis is not. The association appears to be partly explained by prematurity and familial and socioeconomic factors
Microbial extracellular polymeric substances in the environment, technology and medicine
No full textMicrobial biofilms exhibit a self-produced matrix of extracellular polymeric substances (EPS), including polysaccharides, proteins, extracellular DNA and lipids. EPS promote interactions of the biofilm with other cells and sorption of organics, metals and chemical pollutants, and they facilitate cell adhesion at interfaces and ensure matrix cohesion. EPS have roles in various natural environments, such as soils, sediments and marine habitats. In addition, EPS are relevant in technical environments, such as wastewater and drinking water treatment facilities, and water distribution systems, and they contribute to biofouling and microbially influenced corrosion. In medicine, EPS protect pathogens within the biofilm against the host immune system and antimicrobials, and emerging evidence suggests that EPS can represent potential virulence factors. By contrast, EPS yield a wide range of valuable products that include their role in self-repairing concrete. In this Review, we aim to explore EPS as a functional unit of biofilms in the environment, in technology and in medicine.</p
Focal volume optics for composite structuring in transparent solids
Get PDFAchieving high-level integration of composite micro-nano structures with different structural characteristics through a minimalist and universal process has long been the goal pursued by advanced manufacturing research but is rarely explored due to the absence of instructive mechanisms. Here, we revealed a controllable ultrafast laser-induced focal volume light field and experimentally succeeded in highly efficient one-step composite structuring in multiple transparent solids. A pair of spatially coupled twin periodic structures reflecting light distribution in the focal volume are simultaneously created and independently tuned by engineering ultrafast laser-matter interaction. We demonstrated that the generated composite micro-nano structures are applicable to multi-dimensional information integration, nonlinear diffractive elements, and multi-functional optical modulation. This work presents the experimental verification of highly universal all-optical fabrication of composite micro-nano structures with independent controllability in multiple degrees of freedom, expands the current cognition of ultrafast laser-based material modification in transparent solids, and establishes a new scientific aspect of strong-field optics, namely, focal volume optics for composite structuring transparent solids
A Generic Inertial-Response Preserved Active-Damping Control for Grid-Forming Inverters Emulating Synchronous Machines
No full textActively maintaining system frequency and voltage, grid-forming (GFM) inverters that embed a synchronous machine emulation may exhibit interactions with other voltage sources in the grid, leading to poorly-damped power oscillations. To enhance the damping of oscillations, massive studies have been conducted. However, the existing solutions are sometimes implicitly equivalent to one another or mainly concentrate on a single performance aspect of GFM control. In this article, a generic control scheme capable of incorporate established GFM controls is first proposed. Afterwards, two design approaches are developed, simultaneously considering main performance aspects of GFM control: reference tracking, disturbance damping, and inertial response. Employing the developed control scheme with design approaches, three main performance aspects can be quantitatively evaluated in sequence while maintaining explicit relationships with their own indexes. Finally, experimental results from a 2.2 kW GFM inverter have validated the effectiveness of the active-damping controls, design approaches, and theoretical analyses presented in this study.</p
Analyzing How Nordic Corporations Construct Ecological Care Work in an Era of Green Transition
No full textDespite changes to rhetorical strategies in a digital age, the rhetoric of care has emerged across very different contexts, moments and societies in various ways. For this paper, we will focus on care work as it has engaged what is referred to in the Nordics as “the green transition”.The role of care in self-professed “green” companies’ publicly accessible digital rhetoric requires more nuanced and critical attention. By focusing on what we refer to as ecological care work, or what Ganesh (2024) explains as work that seeks to “revitalis[e] and revisualis[e] how to conceive of ways to cope with the severely damaged earth and her people” (p. 8), we aim to more purposefully analyze the ways that eco-friendly Nordic corporations constitute a collective rhetoric of ecological care