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Industrial policy in the era of global value chains: Towards a developmentalist framework drawing on the industrialisation experiences of South Korea and Taiwan
No full textIn this paper, I present a framework for GVC-oriented industrial policy that merges the so-called GVC perspective and the so-called developmentalist perspective—the latter of which is a perspective that industrial policy is most often analysed through, but has been somewhat neglected by the GVC perspective. I argue that the GVC perspective too quickly dismisses the relevance of industrial policy in the East Asian development experience, particularly those in South Korea and Taiwan between roughly 1960 and 1990. By drawing on the industrialisation experiences of these two countries, my framework for industrial policy suggests that the GVC perspective's ideas for industrial policy would be strengthened by more clearly acknowledging the continued importance of three observations by the developmentalist perspective: (a) the need for governments in developing countries to bargain with foreign investors for the purpose of domestic industrialisation; (b) policy design should not only focus on increasing exports, but also focus on replacing some imports with domestic production; and (c) linking up to the value chains of transnational corporations based in high-income countries can bring about some benefits, but ultimately, successful industrialisation necessitates a degree of competing with transnational corporations. State-owned enterprises have historically played an important role in this respect
Factors for eliminating plastic in packaging: The European FMCG experts’ view
No full textThe fast-moving-consumer-goods (FMCG) sector is in the spotlight as a culprit for the current plastic waste problem. However, few studies provide insight into plastic elimination from the FMCG perspective. This qualitative study explores what the FMCG industry encounters when they attempt to address the plastic packaging issue. We conducted 13 semi-structured interviews with selected managers and technology experts in 7 European FMCGs. The analysis uses am original approach, named ‘the Factor Mapping Grid’, developed to stimulate responses from participants and map relationships between different factors. Results include 7 critical factors, and show that FMCG managers believe that pressure from “consumers” is the most prominent factor in reducing plastic. But, consumers are also equally viewed as a barrier to transition and thus act as a double-edged sword for FMCGs, depending on their awareness of plastic as an issue, and their willingness to take actions. All firms view legislation as an important enabler, but acknowledge that this is out of their control. It is evident that for industry, there is a general desire to reduce plastic, but there is a reluctance to be the first, and thus, a ‘we will if you will’ phenomenon is observed
Resting-state Amplitude of Low-frequency Fluctuation is a Potentially Useful Prognostic Functional Biomarker in Cervical Myelopathy.
No full textBACKGROUND: Cervical MRI is the standard diagnostic imaging technique for patients with cervical myelopathy. However, the utility of conventional cervical MRI as a predictive biomarker for surgical recovery remains unclear, partly because of the limited information obtained from this anatomically small area. Brain resting-state functional MRI (rs-fMRI) may help identify candidate predictive biomarkers. Two analytical methods that assess local spontaneous brain activity are widely used for rs-fMRI: functional connectivity between two brain regions and amplitude of low-frequency fluctuation (ALFF). In our previous analysis of functional connectivity, we discovered that brain functional connectivity may be a predictive biomarker for neurologic recovery in patients with cervical myelopathy; however, the functional connectivity analysis identified a correlation with only one clinical outcome (the 10-second test). To establish a comprehensive prediction measure, we need to explore other brain biomarkers that can predict recovery of other clinical outcomes in patients with cervical myelopathy. QUESTIONS/PURPOSES: We aimed to (1) elucidate preoperative ALFF alterations in patients with cervical myelopathy and how ALFF changes after surgery, with a focus on postoperative normalization and (2) establish a predictive model using preoperative ALFF by investigating the correlation between preoperative ALFF and postoperative clinical recovery in patients with cervical myelopathy. METHODS: Between August 2015 and June 2017, we treated 40 patients with cervical myelopathy. Thirty patients met our prespecified inclusion criteria, all were invited to participate, and 28 patients opted to do so (93%; 14 men and 14 women; mean age: 67 years). The 28 patients and 28 age- and sex-matched controls underwent rs-fMRI (twice for patients with cervical myelopathy: before and 6 months after cervical decompression surgery). We analyzed the same study population that was used in our earlier study investigating functional connectivity. Controls had none of the following abnormalities: neck or arm pain, visual or auditory disorders, cognitive disorder, structural brain disorder, a history of brain surgery, mental and neurologic disorders, and medications for the central nervous system. We performed ALFF comparisons between preoperative patients with cervical myelopathy and controls, analyzed postoperative ALFF changes in patients with cervical myelopathy, and performed a correlation analysis between preoperative ALFF and clinical recovery in these patients. Clinical outcomes in the cervical myelopathy group were assessed using the 10-second test, the Japanese Orthopaedic Association upper-extremity motor (JOA-UEM) score, JOA upper-extremity sensory score (JOA-UES), and Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire for upper-extremity function (JOACMEQ-UEF) score before and 6 months after surgery, which is when we believe these scores generally reach a plateau. A total of 93% of those enrolled (26 of 28 patients) were analyzed both preoperatively and postoperatively; the other two were lost to follow-up. RESULTS: The cervical myelopathy group had an increase in ALFF in the bilateral primary sensorimotor cortices (right, cluster size = 850 voxels, t-value = 6.10; left, cluster size = 370 voxels, t-value = 4.84) and left visual cortex (cluster size = 556 voxels, t-value = 4.21) compared with the control group. The cervical myelopathy group had a decrease in ALFF in the bilateral posterior supramarginal gyrus (right, cluster size = 222 voxels, t-value = 5.09; left, cluster size = 436 voxels, t-value = 5.28). After surgery, the bilateral sensorimotor cortices (right, cluster size = 468 voxels, t-value = 6.74; left, cluster size = 167 voxels, t-value = 5.40) and left visual cortex (cluster size = 3748 voxels, t-value = 6.66) showed decreased ALFF compared with preoperative ALFF, indicating postoperative normalization of spontaneous brain activities in these regions. However, the bilateral posterior supramarginal gyrus did not show an increase in ALFF postoperatively, although ALFF in this region decreased preoperatively. Greater levels of ALFF at the left and right frontal pole and left pars opercularis of the inferior frontal gyrus before surgery in the cervical myelopathy group were correlated with larger improvements in the JOACMEQ-UEF score 6 months after surgery (r = 0.784; p < 0.001, r = 0.734; p < 0.001 and r = 0.770, respectively; p < 0.001). The prediction formula, based on preoperative ALFF values in the left frontal pole, was as follows: the predicted postoperative improvement in the JOACMEQ-UEF score = 34.6 × preoperative ALFF value - 7.0 (r = 0.614; p < 0.001). CONCLUSIONS: Our findings suggest that preoperative ALFF may be a biomarker for postoperative recovery in that it predicted postoperative JOACMEQ-UEF scores. To establish a comprehensive prediction measure for neurologic recovery in patients with cervical myelopathy, a multicenter study is underway. LEVEL OF EVIDENCE: Level II, diagnostic study
Bayesian machine learning for the prognosis of combustion instabilities from noise
No full textExperiments are performed on a turbulent swirling flame placed inside a vertical tube whose fundamental acoustic mode becomes unstable at higher powers and equivalence ratios. The power, equivalence ratio, fuel composition and boundary condition of this tube are varied and, at each operating point, the combustion noise is recorded. In addition, short acoustic pulses at the fundamental frequency are supplied to the tube with a loudspeaker and the decay rates of subsequent acoustic oscillations are measured. This quantifies the linear stability of the system at every operating point. Using this data for training, we show that it is possible for a Bayesian ensemble of neural networks to predict the decay rate from a 300 millisecond sample of the (un-pulsed) combustion noise and therefore forecast impending thermoacoustic instabilities. We also show that it is possible to recover the equivalence ratio and power of the flame from these noise snippets, confirming our hypothesis that combustion noise indeed provides a fingerprint of the combustor’s internal state. Furthermore, the Bayesian nature of our algorithm enables principled estimates of uncertainty in our predictions, a reassuring feature that prevents it from making overconfident extrapolations. We use the techniques of permutation importance and integrated gradients to understand which features in the combustion noise spectra are crucial for accurate predictions and how they might influence the prediction. This study serves as a first step towards establishing interpretable and Bayesian machine learning techniques as tools to discover informative relationships in combustor data and thereby build trustworthy, robust and reliable combustion diagnostics
Modeling of stator versus magnet width effects in High-T<inf>c</inf> superconducting dynamos
No full textHigh-Tc superconducting (HTS) dynamos are simple devices for injecting and sustaining dc currents in superconducting coils/magnets. The simple geometry of these devices consists of a superconducting stator(s) and one or more rotor magnets arranged in identical fashion to a classical alternator. However, unlike the classical alternator, the HTS dynamo gives a self-rectified dc output. This somewhat anomalous result is caused by the non-linear resistivity of HTS materials and the large over-critical eddy currents that flow in the stator. As these over-critical currents must recirculate in the HTS stator, the stator's width becomes a key parameter in the physics of the device. In this work we explore the effect of increasing the stator width through using recent advances in modeling these systems. We find that given enough space in the stator, the total sum of circulating and transport currents do not drive the full width of the stator into the flux-flow regime. Operation of the device in this regime results in a non-linear I-V curve, a marked decrease in the internal resistance at open circuit Roc, a saturation of the open circuit voltage Voc, and a short-circuit current Isc that approaches the in-field critical current of the stator itself Ic,min. These behaviors lead to the conclusion that optimal HTS dynamo design should ensure that the stator width be sufficient to avoid current saturation of the superconductor at the target operating current
Scalable coarse integral holographic video display with integrated spatial image tiling
No full textThe dynamic Coarse Integral Holography (CIH) display demonstrated previously can scan the low space bandwidth product (SBP) holographic images delivered by a high bandwidth spatial light modulator (SLM) to form a hologram array for angular tiling of the 3D images for a large field-of-view but only a modest size despite the utilization of the full bandwidth of the SLM in use. In this paper, we propose a scalable approach using seamless spatial tiling of the full bandwidth images generated by two high bandwidth SLMs using a resonant scanner and a high performance galvanometric scanner for a scalable CIH display capable of achieving twice of the final image size and doubled horizontal field-of-view (FOV). A proof-of-concept system is demonstrated with integrated full-parallax holographic 3D images. The proposed method has the potential to tile images generated by more than two SLMs for scalable large size and wide FOV holographic displays
Equivalent seismic coefficients for caisson foundations supporting bridge piers
No full textSafety of a foundation under seismic loading is strongly dependent on the inertial forces transmitted by the superstructure, exchanged with the surrounding soil and acting into the foundation itself. The latter contribution, typically neglected for shallow and pile foundations, should be considered for caisson foundations, much more massive and rigid than the foundation soil. In this paper, the inertial forces acting in caisson foundations during seismic shaking are extracted from the results of a parametric study where different caissons supporting bridge piers are subjected to severe ground motions. The parametric study was carried out in the time domain via 3D Finite Element (FE) dynamic analyses performed in terms of effective stresses but assuming an undrained response of the foundation soil. Non-linear and inelastic soil behaviour was described in the analyses by an elastic-plastic constitutive model with isotropic hardening. In the framework of a pseudo-static approach, the caisson inertia is represented by equivalent horizontal and rotational seismic coefficients, kh eq and krot eq, relating the generalised inertial forces to the caisson weight. The coefficient kh eq turns out to be always remarkably smaller than the maximum value computed at ground surface in free-field conditions, kh max(g.s.). The equivalent seismic coefficients kh eq and krot eq are expressed via empirical relationships as a function of the dynamic properties of the whole system and the seismic input, through dimensionless parameters. Calculation examples are finally given, where safety assessment of bearing capacity is made for different systems using the pseudo-static approach, showing that use of the seismic coefficients computed by the proposed relationships yields results consistent with the ones obtained from the dynamic analyses
Local photodoping in monolayer MoS<inf>2</inf>
No full textInducing electrostatic doping in 2D materials by laser exposure (photodoping effect) is an exciting route to tune optoelectronic phenomena. However, there is a lack of investigation concerning in what respect the action of photodoping in optoelectronic devices is local. Here, we employ scanning photocurrent microscopy (SPCM) techniques to investigate how a permanent photodoping modulates the photocurrent generation in MoS2 transistors locally. We claim that the photodoping fills the electronic states in MoS2 conduction band, preventing the photon-absorption and the photocurrent generation by the MoS2 sheet. Moreover, by comparing the persistent photocurrent (PPC) generation of MoS2 on top of different substrates, we elucidate that the interface between the material used for the gate and the insulator (gate-insulator interface) is essential for the photodoping generation. Our work gives a step forward to the understanding of the photodoping effect in MoS2 transistors and the implementation of such an effect in integrated devices
Microstructural simulation and measurement of elastic modulus evolution of hydrating cement pastes
No full textPredicting the evolution of stiffness in cement paste requires linking morphological properties of the microstructure to the evolution of mechanical properties. Measures are typically difficult to obtain with sufficient time resolution to capture the transitions as the morphology evolves. In this work, we show the combined result 1H NMR and EMM-ARM, a real-time measure of the modulus, with hydration and finite element modelling. Together, these reveal the different mechanisms through which the cementitious matrix gains stiffness, and further hints at links to the morphology of hydrates. A quantitative measure of the roles of percolation, hydrate growth, and space filling is thus provided. A practical outcome of this research is an empirical law linking the stiffness of C-S-H foam to its porosity from the start of the hydration
Primary functional brain connections associated with melancholic major depressive disorder and modulation by antidepressants
No full textThe limited efficacy of available antidepressant therapies may be due to how they affect the underlying brain network. The purpose of this study was to develop a melancholic MDD biomarker to identify critically important functional connections (FCs), and explore their association to treatments. Resting state fMRI data of 130 individuals (65 melancholic major depressive disorder (MDD) patients, 65 healthy controls) were included to build a melancholic MDD classifier, and 10 FCs were selected by our sparse machine learning algorithm. This biomarker generalized to a drug-free independent cohort of melancholic MDD, and did not generalize to other MDD subtypes or other psychiatric disorders. Moreover, we found that antidepressants had a heterogeneous effect on the identified FCs of 25 melancholic MDDs. In particular, it did impact the FC between left dorsolateral prefrontal cortex (DLPFC)/inferior frontal gyrus (IFG) and posterior cingulate cortex (PCC)/precuneus, ranked as the second ‘most important’ FC based on the biomarker weights, whilst other eight FCs were normalized. Given that left DLPFC has been proposed as an explicit target of depression treatments, this suggest that the limited efficacy of antidepressants might be compensated by combining therapies with targeted treatment as an optimized approach in the future