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• The impact of sanctions on local-level violence against civilians is analysed. • Local level data on cash crop productivity and violence by sanctioned, unsanctioned, and pre-sanctioned groups is utilized. • The argument stipulates that sanctions force targeted actors to switch to non-sanctioned cash crops and use violence to extort these goods from civilian producers. • Results suggest sanctions increase sanctioned group violence against civilians rates in cash crop producing locations following months of abundance. • A case study of violence by al-Shabaab before and after the imposition of 2012 charcoal ban is used to contextualize the result and validate the mechanisms. Since the 1990 s, the UN Security Council increased its use of targeted sanctions, yet we know very little about their unintended impact on civilian victimization, especially at the local level. This study argues that imposing sanctions on armed actors may compel them to seize non-sanctioned agricultural resources to replenish lost revenues and use violence to facilitate appropriation. A new dataset on sanctioned group violence in agricultural areas is developed by matching UN sanctions data with information on local attacks on civilians from the UCDP GED and combining these data with a new geographic dataset. Quantitative analyses establish that monthly changes in cash crop productivity affect political violence by sanctioned actors in Africa, while violence by unsanctioned and pre-sanctioned actors is unaffected. A short case study of Somalia validates the hypothesized mechanism by showing that al-Shabaab actively engaged in violence over such substitution dynamics. [ABSTRACT FROM AUTHOR]

[Display omitted] The mechanical properties of artificial spider silks are approaching a stage where commercial applications become realistic. However, the yields of recombinant silk proteins that can be used to produce fibers with good mechanical properties are typically very low and many purification and spinning protocols still require the use of urea, hexafluoroisopropanol, and/or methanol. Thus, improved production and spinning methods with a minimal environmental impact are needed. We have previously developed a miniature spider silk protein that is characterized by high solubility in aqueous buffers and spinnability in biomimetic set-ups. In this study, we developed a production protocol that resulted in an expression level of >20 g target protein per liter in an Escherichia coli fed-batch culture, and subsequent purification under native conditions yielded 14.5 g/l. This corresponds to a nearly six-fold increase in expression levels, and a 10-fold increase in yield after purification compared to reports for recombinant spider silk proteins. Biomimetic spinning using only aqueous buffers resulted in fibers with a toughness modulus of 74 MJ/m3, which is the highest reported for biomimetically as-spun artificial silk fibers. Thus, the process described herein represents a milestone for the economic production of biomimetic silk fibers for industrial applications. [ABSTRACT FROM AUTHOR]

The effects on human health and life have been catastrophic and its adverse economic effects have been profound, as many countries are engaged in lockdowns, social distancing, mobility, and other restrictions. These have caused unprecedented disruptions in production, distribution, consumption, supply chains, tourism, trade, investments, among others. This paper utilises a simple conceptual framework to anticipate the potential adverse impacts of the pandemic on the economy focussing specifically on output, employment, and prices. The anticipated potential outcomes on the above-mentioned global indicators are assessed utilising publicly available data and information. Both qualitative and quantitative information are utilised which are obtained from various primary and secondary sources. Consistent with the potential outcomes, the paper finds and reports severe adverse impact of the pandemic on global production, employment, and prices. Finally, the paper discusses policy responses to combat the crisis by governments and international organisations and discusses some business implications. [ABSTRACT FROM AUTHOR]

• Wage and productivity dynamics in Turkish manufacturing after the transition to democracy are analyzed. • The democratic transition provides conditions for a positive exogenous shock in real wages, followed by rapid productivity growth. • There is evidence of a bi-directional causality between wages and productivity, creating a virtuous cycle. • Large, high-wage, and capital-intensive firms raised productivity more after a wage shock through organizational and technological improvements. • Capital intensity, subcontracting, and labor shedding contribute to productivity growth after a wage shock but at a limited level. We analyze the behavior of plant-level real wages and productivity in Turkish manufacturing after the transition to democracy in 1987 and test for the direction of the causality between these two variables. The Turkish experience is almost an experimental case because successive governments after 1987 let real wages increase rapidly under the pressure of intensifying political competition. Real wages in state-owned enterprises increased by nearly 200% from 1988 to 1993, followed by a 130% increase in real wages in private manufacturing. Our analysis shows that labor and total factor productivity increased at an unprecedented rate during the same period in response to the exogenous wage hikes. Econometric estimates provide strong empirical evidence supporting the hypothesis that there is a bi-directional relationship between wages and productivity, and wage increases do not reduce surplus because the increase in productivity (value added per worker) compensates for increasing wages. [ABSTRACT FROM AUTHOR]

In what order should coauthors be listed on journal articles? The norm in the economics profession is to order them alphabetically. Our examination of 42 leading economics journals for the last 21 years finds that articles not following this norm are shorter (by 3.2 percent), published in less prestigious journals (by 5.0 percent), and receiving fewer citations (by 9.1 percent). This association survives various identification checks. Our findings shed light on how teamwork incentives interplay with social norms — in this case, a deviance from the alphabetic norm punishes alphabetically early members more than it rewards alphabetically late members. [ABSTRACT FROM AUTHOR]

Space manipulator is considered as one of the most promising technologies for future space activities owing to its important role in various on-orbit serving missions. In this paper, a novel adaptive fuzzy neural network (FNN) control scheme is proposed for the trajectory tracking control of an attitude-controlled free-flying space manipulator in the presence of output constraints and input nonlinearities. The parametric uncertainties and external disturbances are also taken into the consideration. First, a model-based controller is designed by using the barrier Lyapunov function (BLF) to prevent the position tracking errors from violating the predefined output constraints. Then, an adaptive FNN controller is designed by using two FNNs to compensate for the lumped uncertainties and input nonlinearities, respectively. Rigorous theoretical analysis for the semiglobal uniform ultimate boundedness of the whole closed-loop system is provided. The proposed adaptive FNN controller can guarantee the position and velocity tracking errors converge to the small neighborhoods about zero, while ensuring the position tracking errors within the output constraints even in the presence of input nonlinearities. To the best of the authors' knowledge, there are relatively few existing controllers can achieve such excellent control performance in the same conditions. Numerical simulations illustrate the effectiveness and superiority of the proposed control scheme. [ABSTRACT FROM AUTHOR]

This paper challenges the mainstream view of potential output and enquires into the supposed effects of Great Recession on potential growth. We identify in the demand-led growth perspective a more promising theoretical framework both to define the notion of potential output and to gauge the long-term effects of a demand slow down. In view of the poor reliability of standard estimates of potential output, we also propose an alternative calculation. This is based on an update of Arthur M. Okun's original method for potential output estimation, which, differently from the estimation methods currently in use, does not rely on the notion of NAIRU, thus being immune to its theoretical and empirical shortcomings. Our calculation, based on a re-estimation of Okun's Law on US quarterly data, shows both how far an economy generally operates from its production possibilities, and how much potential growth is affected by the actual growth of demand over time. These wide margins for expansion of actual and potential output growth imply that a determined policy of demand expansion would create, given time, the very capacity that justifies it. [ABSTRACT FROM AUTHOR]

We consider the effect of emission charges on market structure, output, and emissions in Cournot competition. Assuming myopic decision making and a partial adjustment process, we analyze the impact of emission charges on the stability of duopoly/monopoly and on the level of emissions. We show that where marginal emission charges are increasing in the level of emissions, duopoly is stable. However, where marginal emission charges are decreasing in emissions, duopoly is unstable, and the system converges on monopoly. Equilibrium output and emissions are also shown to be higher under cost structures favoring monopoly than under cost structures favoring duopoly. [ABSTRACT FROM AUTHOR]

This paper investigates the persistent impact of financial crises on economic growth in different regimes of globalization. Relying on a nonlinear dynamic panel representation, this paper explains why the effects of globalization on growth weave into a tale of two opposite narratives. On average, a country experiences higher growth, the more open and integrated it is into the world. However, countries can also experience persistently lower medium-term output growth after a financial crisis, once globalization reaches a certain threshold. The benefits, as well as vulnerabilities, accrue earlier in the globalization process for low-income countries. [ABSTRACT FROM AUTHOR]

• Tested hypotheses for stopped rhamnolipid production in extended stationary phase. • Cause was long N-starvation, not metabolites/oil inhibition or other exhaustion. • Production fully reactivated consistently by replacement with N-containing media. Rhamnolipids are commonly produced using N-limited Pseudomonas aeruginosa fermentations, with active production in the stationary phase. The production, however, stops after certain period. This causes lower productivity and yield because of downtime between batches and the substrate consumed for cell growth. This discontinued production is the significant problem addressed in this study. Rhamnolipid synthesis involves complex regulatory mechanisms, including quorum-sensing systems and alternative sigma factors. Current knowledge on these mechanisms, however, cannot adequately explain the discontinued rhamnolipid production at extended stationary phase. Four hypotheses to causes of this discontinued production were examined here with carefully planned fermentation designs using different initial N-source concentrations and different ways of adding oil and nutrients. Results rejected three of the hypothetical causes: accumulation of rhamnolipids or other inhibitory metabolites, presence of high amounts of oil phase, and exhaustion of non-N nutrients, and supported the hypothesis that the stopped production was caused solely by the extended N-starvation experienced by the cells. The discontinued production was found to be fully reactivated by partial broth replacements with fresh media containing N-source. The finding is important to production economics and promotes new designs to maximize rhamnolipid productivity and yield using extended stationary-phase production instead of short repeated batches. [ABSTRACT FROM AUTHOR]

• Structural contributes to the decline of the wage share. • Two-sector Kaleckian growth model with two consumption and one investment goods. • A rise in the service sector share of output raises the aggregate profit share. This paper looks at structural change as one additional source of decline in the wage share. First, we provide a decomposition of changes in aggregate wage shares into changes due to variations in output composition and in sectoral wage shares for nine OECD countries between 1977 and 2010. We show that the rise in the service sector is a relevant factor in explaining the fall of the wage share, at least for some countries. Next, we develop a two-sector Kaleckian growth model consisting of the service and manufacturing sectors. We assume that structural change is exogenous as it arises from a shift in consumers' preferences or in the saving rate. When mark-ups are relatively higher in the service sector, we show that: i) a shift in the sectoral composition of demand in favor of the service sector good generates a rise in the profit share; ii) a preferences' shock in favor of the service sector raises growth if the price of the service good is sufficiently high. [ABSTRACT FROM AUTHOR]

Multivariable systems are broadly found in industrial processes with nonlinearities, uncertainties, and both input and state couplings. The basic idea to deal with such problems is to remove the input couplings, then estimating all other issues in an online manner followed be a rejection process. This challenge is presented in this research paper, where a decoupling control scheme is proposed based on the decoupler matrix and the Improved Active Disturbance Rejection Control (IADRC) paradigm. A theoretical analysis based on Hurwitz criterion followed by numerical simulations on a general industrial nonlinear, uncertain and highly coupled Multi-input Multi-Output (MIMO) system proved the validity of the proposed scheme in controlling such kinds of systems. Performance comparisons with the Conventional ADRC (CADRC) based decoupling control scheme are also included. [ABSTRACT FROM AUTHOR]

• We provide new empirical evidence on the way in which the import of inputs impacts on firm-level productivity. • We find a positive association between imports into a sector and firm productivity and a productivity premium for firms using imported inputs. • There are also productivity gains downstream for firms using domestically-produced inputs from more import-intensive sectors. • We find suggestive evidence that import competition leads to product differentiation and better quality domestically-produced inputs. • Ignoring gains from trade through the supply chain may underestimate the impact of trade on the productivity of domestic firms. This paper explores how competition-induced productivity gains from imports in intermediate producing sectors transmit through the supply chain. Based on firm-level panel data from Vietnam, we show that in addition to the productivity premium associated with importing intermediate inputs, firms that use domestically-produced inputs from more import-intensive sectors also have higher productivity. We find evidence that import competition leads to product differentiation, in particular higher quality output in sectors where there is greater scope for quality variation, leading to better quality domestically-produced inputs. We also find evidence that non-importing firms that experience productivity gains due to greater import intensity in upstream sectors change their input mix and become more capital intensive. We conclude that ignoring the gains from trade through this mechanism may significantly underestimate the impact of trade on productivity. [ABSTRACT FROM AUTHOR]

• This study investigates how ASM and LSM affect local conflict in Eastern DRC. • We exploit variation in conflict, mineral prices and LSM across space and time. • Rising mineral prices increase conflict around ASM, but not around LSM. • The expansion of LSM production activities decreases battles but increases riots. • When LSM production expands in ASM areas, violence against civilians rises. Existing research suggests a strong link between mining and local conflict but makes no distinction between artisanal and industrial mining. We exploit variation in mineral prices and the granting of industrial mining concessions to investigate how the mode of extraction affects conflict in Eastern Congo. Rising mineral prices increase battles over artisanal mines, indicating competition between armed groups. This effect is much less pronounced for industrial mining. Moreover, the expansion of industrial mining decreases battles, suggesting that companies can secure their concessions. Such expansion does, however, trigger riots, and, when it crowds out artisanal mining, also increases violence against civilians and looting. In line with case-study evidence, these negative effects only materialize when industrial mining companies expand their activities from the research to the production phase. [ABSTRACT FROM AUTHOR]

• For most scenarios, densifying biomass does not improve the economics. • Densification is economically advantageous when there is a high feedstock competition. • The plant size of a densification facility has a minimal impact on the overall economics. Biomass such as switchgrass can be converted to renewable gasoline and diesel (RGD) fuels via integrated fast pyrolysis and hydrodeoxygenation. However, the low bulk density of biomass feedstocks produces relatively high transportation costs, driven by the large volumes needed to supply biorefineries. Densification can reduce transportation volumes, and therefore transportation costs for bioenergy production. However, the additional costs of biomass densification, along with decreases in overall mass and energy yields, influence the overall economic performance of RGD production. This study investigated the techno-economic impacts of pelletizing, torrefying, or pyrolyzing the biomass at distributed facilities prior to upgrading the intermediates to RGD at a centralized facility. Eight scenarios were considered. When there is no feedstock competition, biomass densification at the distributed facility was shown to reduce the transportation cost by 20%–50%. However, the capital and operating costs required for densifying biomass increased the total cost of RGD production by 3%–35% compared to RGD made from non-densified biomass. The cost of making RGD from densified biomass was only reduced below the cost of making RGD from non-densified biomass for the case when the fraction of land surrounding the biorefinery facility allocated to the biomass cultivation is less than 0.25. This finding is attributed to the high cost of transporting non-densified biomass from a larger procurement radius. Sensitivity analysis indicated that RGD fuel yield, densification costs, project investment, and the rate of return all have significant impacts on the overall economics of RGD production. [ABSTRACT FROM AUTHOR]

• We developed a comprehensive and spatially disaggregated typology to identify and locate major food security bottlenecks. • The typology is conceptually sound, operationally flexible, and less data intensive. • Intervention types and levels of production, access, and utilization efficiency were identified for rural areas in the DRC. • The efficiency profile of nine high-priority territories was discussed in more detail using secondary data. • The proposed approach can be adjusted to fit the conditions of most developing countries. In this paper we develop a typology to help design and improve spatial targeting of food and nutrition security (FNS) interventions. Using a comprehensive framework, the proposed approach allows for the broad identification and location of major food security bottlenecks. The resulting typology is based on an amendable demarcation of areas in a four-indicator diagram representing the four core dimensions of FNS. The proposed typology is applied to the rural territories of the Democratic Republic of the Congo (DRC). Despite a continuum of heterogenous development challenges across the country, the typology helps identify clusters of territories that suffer from production, access, and utilization constraints. For the nine territories (out of 145) with the highest child stunting levels, we identify four broad intervention zones and analyze their efficiency profile in more detail. Despite its reductionist nature, our typology is conceptually sound, operationally flexible, and less data intensive, important features to promote evidence-based policymaking in contexts characterized by imperfect and scarce data. [ABSTRACT FROM AUTHOR]

• Empirical and theoretical contribution to debates on the relationships between neoliberalism, fisheries management, and the institutionalization of the commons. • Uses the analytic framework of governmentality to identify important shifts within fisheries management, as demonstrated through the institutional approach to the commons. • Demonstrates how efforts to implement community-based management in the Irish lobster fisheries represents continuity and discontinuity with the long tradition of liberal thought and biopolitical "improvement". • Develops the concept of "improvement" for analyzing dynamic process of neoliberal fisheries management (and environmental governance more broadly). • Argues for greater criticality when it comes to affirming the benefits of the commons as an alternative to dominant forms of economic production and decision-making. This paper contributes theoretically and empirically to debates on the relationship between neoliberalism and the institutionalization of the commons through an analysis of recent efforts to implement community-managed lobster fisheries in Ireland. This initiative has been influenced by international examples of co-management systems in small-scale, inshore fisheries, and is presented as a "third way" for resource management, moving beyond the limited management choice of privatization or centralized state control. The paper is based on interviews and fieldwork with the fisheries managers, scientists, and inshore fishermen involved in the development of the co-management plan. In the paper, I use the analytic framework of governmentality to examine how these efforts to institutionalize the fisheries commons represent both continuity and discontinuity with the long tradition of liberal thought and biopolitical "improvement". I argue that the continuity stems from the initial formulation of the problem of overfishing as one of unregulated exploitation of a resource; the novelty lies in the critique of existing institutional models, namely privatization and state regulation, that fail to adequately reflect and enable the capacities of local communities to self-manage the resources they exploit. Understanding neoliberal governmentality in terms of "improvement" helps us to understand and take more seriously the rationale behind efforts to devise better institutional responses to the problem of overfishing. The concept of "improvement" helps to broaden the analysis of neoliberalism beyond an often narrowly defined focus on market mechanisms and profit incentives; it shifts the focus of analysis away from the regulatory moments of "enclosure" to the ongoing, often frustrated efforts to align fishers' economic interests with the "long-term" common good. The article argues for a more ambivalent reading of the commons that places greater focus on how localized, collective action can be valued and incorporated within evolving governmental and economic arrangements. [ABSTRACT FROM AUTHOR]

Highlights • A new theoretical model of a dual-wavelength laser with reabsorption effect is presented. • The no gain competition dual-wavelength lasers are presented for the first time. • The total output power was higher than 3.6 W, the conversion efficiency was >17%. • The fluctuations in the output powers of two wavelength lasers were 1.62 and 2.18%. • The measured M2 values for 912 nm and 1064 nm lasers were 1.35 and 1.28. Abstract In this study, based on the intra-cavity pumped dual-wavelength theoretical model, a reabsorption effect is introduced into a quasi-three-level laser, and a new theoretical model of a dual-wavelength laser with reabsorption effect is presented. Through experiments, the output characteristics of no gain competition 912 nm and 1064 nm dual-wavelength lasers with Nd:GdVO 4 and Nd:YVO 4 are presented for the first time. Results showed that at an incident pumping power of 38.9 W, the total output power was generally higher than at 3.6 W (1.4 and 2.2 W at 912 nm and 1064 nm, respectively) and the overall optical-to-optical efficiency was > 17%. The fluctuations in the output powers of the 912 nm and 1064 nm lasers were 1.62 and 2.18%, respectively. However, the fluctuation in the total output power was only 0.28% at a pumping power of 27.7 W. The laser mode was TEM 00 , and the measured M2 values for 912 nm and 1064 nm lasers were 1.35 and 1.28, respectively, under a pumping power of 30 W. [ABSTRACT FROM AUTHOR]

The problem of output regulation for general multivariable linear systems has been solved in the 70s, in the seminal works of Francis, Wonham and Davison, under the assumption that the reference signals and the disturbances acting on the system are generated by a known exogenous linear system (the exosystem). The regulator is designed to embed an internal model of the exosystem, which ensures that asymptotic regulation is maintained under arbitrary plant perturbations that do not destroy linearity and closed-loop stability. This robustness property, however, is inexorably lost whenever the internal model does not match exactly the exosystem. In this paper we endow the linear regulator with a discrete-time adaptive unit that adapts the regulator's internal model on the basis of the closed-loop evolution. Compared to existing approaches, adaptation here is cast as an identification problem, and the corresponding optimal predictor is designed independently from the underlying control system. This permits to separate stabilization and adaptation, thus naturally handling general non-square multivariable non minimum-phase plants. Closed-loop stability is guaranteed and, if the dimension of the internal model is large enough and a persistency of excitation condition is fulfilled, asymptotic regulation is achieved for references and disturbances generated by an unknown exosystem. Robustness to parametric uncertainties is inherited by the linear regulator and robustness to additional unmodeled disturbances is proved to hold. [ABSTRACT FROM AUTHOR]

In this paper, an adaptive output feedback control via command filtered backstepping is proposed for a class of uncertain nonlinear systems with full-state constraints. Firstly, the "explosion of complexity" problem inherent in all the existing results of backstepping-based full-state constraints area is solved by the proposed control. Secondly, a state observer is designed to estimate the immeasurable states and the command filtered technology is utilized to cope with the problem in the present backstepping-based results of constrained nonlinear systems. Thirdly, the barrier Lyapunov functions are constructed to ensure the constraints are not transgressed. Then, an error compensating mechanism is developed to cope with filtering errors and only one adaptive law is needed for the full-state constrained nonlinear systems. An example is given to illustrate the validity and potential of the new design scheme. [ABSTRACT FROM AUTHOR]

We propose a new algorithm for controlling the transient behavior of the tracking error for nonlinear systems with arbitrary relative degree. In tracking problems, the transient behavior of the error is more important than the behavior of its derivatives. We introduce a concept of virtual output, which converts an arbitrary relative degree system into a relative degree one system. The virtual output is chosen in such a way that the difference between the virtual output and the tracking error can be made arbitrarily small all the time. Assuming that the state derivatives are not available for feedback we use a high-gain observer to estimate the derivatives and construct the virtual output. [ABSTRACT FROM AUTHOR]

This work studies mean-square stabilizability via output feedback for a networked linear time invariant (LTI) feedback system with a non-minimum phase plant. In the feedback system, the control signals are transmitted to the plant over a set of parallel communication channels with possible packet dropout. Our goal is to analytically describe intrinsic constraints among channel packet dropout probabilities and the plant's characteristics in the mean-square stabilizability of the system. It turns out that this is a very hard problem. Here, we focus on the case in which the plant has relative degree one and each non-minimum zero of the plant is only associated with one of control input channels. Then, the admissible region of packet dropout probabilities in the mean-square stabilizability of the system is obtained. Moreover, a set of hyper-rectangles in this region is presented in terms of the plant's non-minimum phase zeros, unstable poles and Wonham decomposition forms which is related to the structure of controllable subspace of the plant. A numerical example is presented to illustrate the fundamental constraints in the mean-square stabilizability of the networked system. [ABSTRACT FROM AUTHOR]

• The uncertainty analysis comprises multiple hydrological variables. • Some of these variables represent catchment response at interior catchment locations. • Flexible and reliable uncertainty prediction despite various different error structures. • Appealing for operational hydrology as the method is simple, fast and robust. Regardless of the complexity of the hydrological model employed, uncertainty assessment (UA) is predominantly performed for the aggregated catchment response discharge. For coupled integrated models that simulate various hydrological states and fluxes on a grid cell basis, this represents a severe shortcoming. We test a simple data-driven technique (k-NN resampling) to evaluate its ability to provide reliable residual uncertainty estimates for the multi-variable (discharge, hydraulic head, soil moisture and actual evapotranspiration), deterministic output of two coupled groundwater-surface water models with different complexities. Being a nonparametric method, no explicit prior assumptions about the error distribution of different hydrological variables are required. When conditioning the algorithm, we propose to limit the number of error lags to be included based on inspection of the partial autocorrelation function (PACF). Our results confirm previous findings regarding reliability and robustness of the k-NN technique for discharge simulations and conclude that k-NN resampling also provides reliable and robust results for other variables like hydraulic head, soil moisture and actual evapotranspiration, even for underlying hydrological models with varying levels of performance. The 90% prediction intervals (PI) capture the observations in the testing period satisfactorily for all hydrological variables (92.6–97.3%), while Alpha indices (0.84–0.95) indicate very reliable PIs for all error quantiles. Differences in error structure between hydrological variables are successfully inferred from historical data and reflected in the results. We conclude that k-NN resampling represents a potent, cost-efficient UA technique for applications in operational hydrology, facilitating a near-simultaneous, easy uncertainty assessment for various outputs of computationally heavy hydrological models. [ABSTRACT FROM AUTHOR]

In this paper we present an effective algorithm for creating minimal-size sorting networks. Our approach is based on incrementally constructing sets of sorting networks, starting from a specified prefix and adding gradually new comparators. At each step, in order to limit the size of these sets, only the most promising candidates are considered. We introduce a novel rule for implementing the selection of candidates, based on analyzing the structure of a network's output, instead of simply considering its size. For 16 wires, the running time necessary to determine a sorting network was reduced up to 90 times, compared to state-of-the-art results [21]. [ABSTRACT FROM AUTHOR]

Abstract This paper is concerned with the fault detection (FD) filter design problem for the discrete-time nonlinear systems with past output measurements and sensor saturation. The considered discrete-time nonlinear systems are described by T–S fuzzy models. A decomposition method is used to deal with the characteristics of sensor saturation. A new FD filter with past output measurements is firstly proposed by using the Lyapunov functional method. Subsequently, the design conditions are given in terms of convex problems constrained by linear matrix inequalities (LMI). Moreover, it is shown that the FD filter with past output measurements can achieve better FD performances than the existing ones with current output measurements. Finally, some simulation results are given to illustrate the advantages of the proposed design method. [ABSTRACT FROM AUTHOR]

Abstract This paper is concerned with the finite-time static output feedback H ∞ controller design problem for a type of nonlinear continuous-time descriptor semi-Markov jump systems (S-MJSs) via Takagi–Sugeno (T–S) fuzzy model, where the transition rates are time-varying and dependent on sojourn time. Firstly, based on the stochastic Lyapunov functional, sufficient conditions on singular stochastic H ∞ finite-time boundedness (SS H ∞ FTB) for continuous-time T–S fuzzy descriptor S-MJSs are given. Then, in order to design the static output feedback controller easily, the closed-loop system is represented in an augmented form. Furthermore, based on the lower and upper bounds of the time-varying transition rates, and by using the matrix inequality decoupling technique, a novel linear matrix inequality (LMI) condition on SS H ∞ FTB of closed-loop system is presented. Meanwhile, the static output feedback controller is developed in terms of LMIs. The proposed design method doesn't impose any constraints on system matrices or slack variables, which shows less conservative results. Lastly, numerical examples are given to demonstrate the effectiveness of the obtained methods. [ABSTRACT FROM AUTHOR]

Abstract This paper is concerned with the study of strictly negative imaginary (SNI) systems and the problem of synthesizing a controller rendering a linear fractional system SNI. First, a set of necessary and sufficient conditions are developed for an SNI lemma without imposing minimality assumptions. The proposed lemma supports both the analysis and synthesis of SNI systems. Then, a set of sufficient conditions, based on the solution of algebraic Riccati equations, is provided for the solution of the SNI synthesis problem. Finally, an illustrative example demonstrates the usefulness of the results given herein. [ABSTRACT FROM AUTHOR]

Abstract Output synchronization of nonlinear heterogeneous networked systems has been well investigated within a two-step framework. A reference model is designed for each agent and they achieve consensus through a proper collaborative control strategy. Then, a local regulation controller is constructed to drive each agent's output to the desired trajectory generated by its reference model. The local regulation controller was studied mainly based on the internal model principle. As the two steps occur concurrently, a small gain condition must be satisfied between them when the setting is on output communication that allows only agent outputs to be transmitted over network. In this paper, we consider a novel feedforward design that does not rely on internal model but a reference model of a sufficiently high relative degree. With such a design, local regulation can be separately achieved and hence the small gain condition is no longer required, which much simplifies the design when agent dynamics do not contain uncertainties. [ABSTRACT FROM AUTHOR]

Abstract This paper addresses the problem of global adaptive stabilization by output-feedback for a class of uncertain nonlinear systems with unknown growth rate and unknown output function. By constructing a suitable Lyapunov function, a new systematic design scheme is proposed to derive an adaptive output-feedback controller with appropriate design parameters based on a dynamic high-gain, under which the system states can be globally regulated to zero. Because the proposed method uses the adaptive technique rather than the time-varying one, it does not require a priori known information about either the growth rate or the upper and lower bounds of the derivative of the unknown output function. This makes the investigated system substantially different from the existing results and also highlights the main contributions of the paper. A practical example is presented to show the validity of the theoretical results. [ABSTRACT FROM AUTHOR]

Highlights • The concept of inertia in physics is introduced into MSSs reliability analysis. • A critical threshold is set for each deteriorating output performance. • Both constant and random thresholds are considered. • Analytical deductions are presented to compare the availability variations. Abstract For the repairable multi-state component (MSC), we introduce a continuous-time Markov process to analyze the availability of the element in this paper. When output performance of the MSC is lower than demand but higher than zero, the component will not fail to work immediately under some circumstances. Based on the concept of inertia in physics, the inertial effect of deteriorating output performances is considered. The influence of inertial effect makes the component operate longer than ever before, resulting in failure delay. To measure the probability influence of inertial effect on availability quantitatively, a critical threshold is set for each deteriorating output state. Both non-negative constants and random variables of the critical thresholds are modeled respectively. Comparing with the original system described with a Markov process, the new situation with inertial effect is recorded as the new system and described with a generic stochastic process. Availability variations of the original system and the new system show the influence of inertial effect on the reliability. A numerical example of a power supply system, which is a typical multi-state system (MSS), is presented to illustrate the results obtained. Relevant studies may be extended in many fields such as queuing theory and quality management. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

The treatment of undesirable outputs in Data Envelopment Analysis (DEA) has received great research attention recently. As such and as are presented in this work, there are four possible options to deal with those: 1. ignoring them from the production function, 2. treating them as regular inputs, 3. treating them as normal outputs and 4. performing necessary transformations to take them into account. Also new model propositions for their treatment are being presented. Each method brings with it, benefits and drawbacks which each researcher should take into account at every stage of their research and assesses which method is more appropriate to be used. [ABSTRACT FROM AUTHOR]

Abstract Intense white-light color emission of lanthanide-doped core-shell structured particles at microscale level was presented under 980 nm excitation. The prepared NaYF 4 :Yb/Er@ NaYF 4 :Yb/Tm microcrystals not only can effectively prevent the deleterious cross-relaxation that occurs between the Er3+ and Tm3+ due to the location of the activator ions within different layers, but also possess a high luminescence efficiency due to dimensions of the micro-scale structure. The core-shell structured microcrystals presented satisfactory capacity for color control in the white region. The results show great potential in attaining white light-emitting diodes within the field emission display on specific device applications. Furthermore, the core-shell microcrystals emit white-light that presents obvious and distinct lifetimes of green, red, and blue emissions, which could achieve multicolor emissions by setting a suitable delay time. This feature demonstrates that the core-shell structured microrods offer practical use as security ink to prevent forgery, such as in identifying currency. Highlights • Intense white-light color emission of core-shell microrods was presented. • Crosstalk between activators in core and shell layer is prevented even without filter layer. • White-light with high luminescence efficiency and good white color stability. • The luminescent lifetime of blue, green, and red emissions differs a lot in samples. • Multicolor emission was achieved by setting a suitable delay time. [ABSTRACT FROM AUTHOR]

Abstract This paper aims at addressing the adaptive neural control problem for switched nonlinear systems with output hysteresis and unmodeled dynamics. The switching law in this study is arbitrary. In our model, the unmodeled dynamics are assumed to be of input-to-state practical stability (ISpS). With the help of this assumption, a dynamic normalizing signal is constructed to dominate the unmodeled dynamics. And then, a direct adaptive neural state-feedback control scheme is developed with the help of approximation-based backstepping. The stability analysis shows that the system output is convergent to an adjustable small region of zero asymptotically, and furthermore, all the closed-loop signals are bounded. Finally, we further present two simulation examples to verify the effectiveness of our control scheme. [ABSTRACT FROM AUTHOR]

This paper presents a switched-capacitor (SC) bandgap reference (BGR) with second-order curvature compensation for ultra-low power systems. The gate-source voltage of a sub-threshold MOSFET is proposed to implement the second-order curvature compensation voltage in this work. And then, a SC network is used, not only to add the second-order voltage and the first-order one together, but also to fulfill the summing weight effectively and precisely. In this way, the silicon area and power consumption can be reduced simultaneously. Furthermore, the design methodology of summing weight is investigated, and thus the temperature coefficient (TC) can be significantly reduced. The proposed SC-BGR was implemented and simulated in a CMOS 0.18 μm process, the average output voltage is 426.1 mV, achieving a TC of 17.6 ppm/°C from −20 to 100 °C under a 0.5 V minimum supply voltage. With the help of the SC architecture, a small chip area of 0.0975 mm2 is achieved with only 37.8-nW power consumption. [ABSTRACT FROM AUTHOR]

This paper proposes a single-inductor dual-output (SIDO) DC-DC boost converter with Near-threshold Start-up voltage which adopts ordered-power-distributive-control (OPDC) method. A load-dependent feedback loop control is proposed to effectively suppress cross-regulation between the outputs, which is simple and flexible. Meanwhile, a two-step start-up scheme which makes the start-up circuit simpler has been put forward. It makes sure that the SIDO converter can adjust and complete near-threshold start-up depending on different load currents. This SIDO DC-DC converter has been fabricated in 0.18 μm CMOS process. The minimum starting voltage is 0.5 V, and the simulation results show that the cross-regulation suppression circuit successfully reduce the voltage cross-regulation ratios VCR1 and VCR2 to 0.2 mV/mA and 0.11 mV/mA, respectively. In normal operation, both of the output voltages and its corresponding maximum output currents are 1.2 V/40 mA and 1.8 V/40 mA. A maximum conversion efficiency of 91% can be achieved. [ABSTRACT FROM AUTHOR]

• A study about the appearance of hand-placed dots in traditional stippling. • A discussion of stipple dot reproduction on typical output devices. • A discussion the effects of dot attributes on the perception of digital stippling. We contribute an in-depth analysis of the characteristics of traditional stippling and relate these to common practices in non-photorealistic stippling as well as to the abilities and limitations of existing printing and display technologies. Based on the properties of traditional stipple dots which depend on the used pens and paper types, we focus on a perceptual study of digital stippling that further informs our discussion and work toward an understanding of the requirements for the reproduction of hand-made stippling. To allow artists and illustrators to replicate the stippling process faithfully in the digital domain, we thus extract guidelines from the study results such as that the characteristics of real dots must be reproduced because they are perceived and that the results must be adjusted to the different properties of output devices. [ABSTRACT FROM AUTHOR]

Highlights • A build-up structure with pendulums fixed on a balanced platen was introduced. • The side force and additional moment had influences on the build-up system output. • Smaller side force and additional moment were generated in the build-up structure. • A 60 MN build-up system of the special structure was measured and verified. Abstract As the primary force standard in the super large force range, force transducer build-up system played an important role to calibrate the build-up force standard with a capacity over 20 MN. To enhance the accuracy of the build-up system, the influence of build-up structure on the output of the build-up system was investigated. The parasitic components, including the side force and the additional moment, in three different build-up structures were analysed, and compared by the finite element simulation. The experiments of three 300 kN build-up systems of the three structures and a 60 MN build-up system were carried out. The experiment showed that the side force and the additional moment applied to the transducer had significant influences on the output of the transducer. The larger side force and additional moment, the larger the position error and the indication error of the BUS were. The side force and the additional moment should be minimized during the build-up structure design. The pendulum used in the build-up system could significantly reduce the additional moment generating on the transducer, especially after the pendulums were fixed on the balanced platen. The special build-up structure with the pendulum fixed on a balanced platen was verified as a proper build-up structure. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a backstepping solution of the periodic output regulation problem for general linear heterodirectional hyperbolic systems. By utilizing a time-varying signal model, regulators are determined for a general class of periodic reference inputs and disturbances. A systematic design procedure is developed for the state feedback regulator by solving the periodic regulator equations. In order to obtain an output feedback regulator, a time-varying finite-dimensional reference observer and a time-varying infinite-dimensional disturbance observer are determined. For this, a systematic backstepping approach is provided. The results of the paper are illustrated for a 4 × 4 hyperbolic system with periodic triangle reference inputs and sinusoidal disturbances subject to time-varying frequencies. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we present an output feedback based design of event-triggered sliding mode control for delta operator systems. For discrete-time systems, multi-rate output sampling based state estimation technique is very useful if the output information is available. But at high sampling rates, the discrete-time representation of the system using shift operator becomes numerically ill-conditioned and as a result, the observability matrix becomes singular as the sampling period tends to zero. Here, a new formulation of multi-rate state estimation (MRSE) for a small sampling period is presented. We first propose a new observability matrix and then discuss its relationship with the observability matrix defined in the conventional sense. For the delta operator system with matched uncertainty, we have presented the design of MRSE based sliding mode control (SMC). Additionally, to make the control efficient in terms of resource utilization, MRSE based event-triggered SMC is proposed. The absence of Zeno phenomenon is guaranteed as the control input is inherently discrete in nature. Finally, the effectiveness of the proposed method is illustrated through numerical simulations, considering a ball and beam system and a general linear system as a numerical example. [ABSTRACT FROM AUTHOR]

Abstract The problem of sampled-data observer design is addressed for a class of state- and parameter-affine nonlinear systems. The main novelty in this class lies in the fact that the unknown parameters enter the output equation and the associated regressor is nonlinear in the output. Wiener systems belong to this class. The difficulty with this class of systems comes from the fact that output measurements are only available at sampling times causing the loss of the parameter-affine nature of the model (except at the sampling instants). This makes existing adaptive observers inapplicable to this class of systems. In this paper, a new sampled-data adaptive observer is designed for these systems and shown to be exponentially convergent under specific persistent excitation conditions that ensure system observability and identifiability. The new observer involves an inter-sample output predictor that is different from those in existing observers and features continuous trajectories of the state and parameter estimates. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the cooperative output regulation problem for linear multi-agent systems with actuator faults is considered. It is assumed that the actuator faults are outage faults and loss-of-effectiveness faults. First, a distributed finite-time observer is designed to estimate the state of the exosystem. Based on the state of the finite-time observer, a distributed adaptive fault-tolerant controller is designed. Then, it is shown that the cooperative output regulation problem can be solved with the proposed fault-tolerant controller. Compared with the existing cooperative output regulation results, a novel lemma is introduced to guarantee the solvability of the regulator equations under actuator faults, and the developed controller is effective to compensate the actuator faults. Finally, a simulation example is presented to show the validity of the proposed method. [ABSTRACT FROM AUTHOR]

Highlights • Recent studies have shown that targeting an undervalued real exchange rate stimulates economic growth by expanding tradable sector output. • We examine whether such growth reduces gender gaps in labor force participation by improving labor market opportunities for women. • We find that currency undervaluation improves female labor force participation and reduces gender gaps in labor force participation. • This finding is stronger for developing countries and is robust to various specification checks and estimation techniques. • Findings suggest that the operative channel is an expansion of female employment in manufacturing and industrial sectors. Abstract While a large literature examines the role of fiscal policy in reducing gender gaps in labor market outcomes, scant evidence exists for the role of monetary and exchange rate policies in doing so. Recent studies have shown that targeting an undervalued real exchange rate stimulates economic growth by expanding tradable sector output. We examine whether such growth reduces gender gaps in labor force participation by improving labor market opportunities for women. Using a comprehensive cross-country dataset from 1960 to 2015 for a maximum of 103 countries, we test whether there is a robust relationship between currency undervaluation and female labor force participation. We find that countries that maintain an undervalued real exchange rate realize an increase in female labor force participation, and a corresponding decline in the difference between male and female labor force participation rates. This finding is particularly pertinent for developing countries and is robust to various specification checks as well as different estimation techniques. We also provide suggestive evidence that the operative channel is an expansion of female employment in manufacturing and industrial sectors. Our findings have important policy implications, particularly for countries in earlier stages of their development. Our results indicate that the positive effect of undervaluation on female labor force participation is stronger in developing countries, implying that there may be opportunities for interventions to target a more undervalued real exchange rate in these countries. Hence, competitive exchange rate policies matter not only for raising long-term growth potential, but also for reducing longstanding gender disparities in labor force participation. [ABSTRACT FROM AUTHOR]

Abstract Reworking defective items any in multi-stage production systems have become a common issue for production industries. Due to random defective rate of production, it may contain several imperfect items as wastes. The reduction of those wastes through reworking in each stage of a cycle or at the end of stage of a cycle by an identifying opportunity design technique. A design is developed for making such type multi-stage production system. For this, imperfect products may be reworked within each cycle while avoiding any shortages or reworked after end cycle with shortages in each cycle. The aim of the model is to diminish wastes by reworking strategy for minimizing the total cost. For this purpose, the proposed study develops a multi-stage production model for an optimum production batch policy with random production of imperfect products. Two-stage inspection is considered for detecting those faulty products and ensuring that there are no faulty items anymore. As it is a long-run production system, setup cost plays an important role, an attempt at setup cost reduction has been made to reduce it by a discrete investment for each stage along with a budget constraint. The Lagrangian method is employed to solve the model and the global minimum cost for optimal decision variables is obtained. Ten lemmas are established to obtain the global optimum solution. The model shows that a large investment to reduce the setup cost is better than a constant setup cost. It is found that the imperfect items should be reworked after the end cycle. There are eight numerical examples, eight special cases, a sensitivity analysis of the key parameters, and sixteen graphical representations to demonstrate the proposed model. [ABSTRACT FROM AUTHOR]

This paper investigates the design problem of output feedback control to a type of quasi-linear high-order systems containing time-variant coefficient matrices which include time-variant parameters and system variables. Based on the solution to a class of high-order generalized Sylvester matrix equation, we can design the left and right closed-loop eigenvectors and obtain two groups of arbitrary parameters, further establish a general complete parametrized expression for a quasi-linear high-order output feedback controller. By the presented parametric approach, the closed-loop system can be transformed into a linear time-invariant one with the desired eigenstructure. Finally, a nonlinear feedback synchronization problem of Genesio-Tesi and Coullet chaotic systems is presented to prove the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Robust output feedback model predictive control (MPC) of linear time-varying (LTV) systems subject to bounded state and output disturbances is considered in this paper. The output feedback controller is designed in such a way that the observer is time-varying so the unknown state and the observer state are bounded by the tubes whose center is the state of the nominal LTV system that is steered to the origin. The on-line computational complexity is similar to that required for nominal MPC for LTV systems. Robust stability is ensured by using the notion of Lyapunov functions. The controller design is illustrated via two examples in chemical processes. The results show that the proposed output feedback controller can guarantee robust stability and constraint satisfaction of the LTV systems in the presence of bounded state and output disturbances. [ABSTRACT FROM AUTHOR]

Abstract Enhancing the robustness of output feedback control has always been an important issue in hydraulic servo systems. In this paper, an output feedback model predictive controller (MPC) with the integration of an extended state observer (ESO) is proposed for hydraulic systems. The ESO was designed to estimate not only the unmeasured system states but also the disturbances, which will be synthesized into the design of the output prediction equation. Based on the mechanism of receding horizon and repeating optimization of MPC, the output prediction equation will be updated in real time and the future behavior of the system will be accurately predicted since the disturbances are compensated effectively. Hence, the ability of the traditional MPC to suppress disturbances will be improved evidently. The experiment results show that the proposed controller has high-performance nature and strong robustness against various model uncertainties, which verifies the effectiveness of the proposed control strategy. Highlights • An output feedback model predictive controller is proposed for hydraulic actuators with active disturbance compensation. • Extended state observer and model predictive control are effectively integrated, for uncertain nonlinear hydraulic system model. • Theoretical analysis is given of the closed loop system. • Experimental verification is given for a hydraulic servo system. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the relative position tracking and attitude synchronization problem of a chaser spacecraft rendezvous and docking with an uncontrolled tumbling target in the presence of external disturbances and actuator saturation. By combining the extended state observer technique with backstepping control methodology, a robust output-feedback control strategy with no precise motion information of the tumbling target is proposed. Moreover, a particular Nussbaum-type function is introduced to compensate for the nonlinear terms arising for actuator saturation. Within the Lyapunov framework, it is then shown that the proposed control strategy can guarantee the relative position and attitude errors converge into small regions containing the origin. Finally, numerical simulations are carried out to verify the effectiveness of the designed control strategy. Highlights • An ESO-based output control strategy is investigated to study the control problem of spacecraft proximity operations. • The proposed control strategy removes the need for full-state measurements, and compensate for the actuator saturation. • The presented controllers can guarantee the ultimate boundedness of the closed-loop system via Lyapunov theory. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we present a hybrid architecture for developing a system combination model that works in three layers to achieve better translated outputs. In the first layer, we have various machine translation models (i.e. Neural Machine Translation (NMT), Statistical Machine Translation (SMT), etc.). In the second layer, the outputs of these models are combined to leverage the advantages of both the systems (i.e SMT and NMT systems) by using the statistical approach and neural-based approach. But each approach has some advantages and limitations. So, instead of selecting an individual combined system's output as the final one, we apply these outputs in the final layer to produce the target output by assigning appropriate preferences to SMT based and neural-based combinations. Though there are some techniques for system combination but no such approach exists which uses preferences from various system combination models (statistical and neural) for the purpose of better assembling. Empirical results show improved performance in the terms of translation accuracy. Our experiments on two benchmark datasets of English–Hindi and Hindi–English pairs show that the proposed model performs significantly better than the participating models. Apparently, the efficacy of proposed model is significantly better than the state-of-the art machine translation combination systems (6.10 and 4.69 BLEU points for English-to-Hindi, and Hindi-to-English, respectively). Graphical abstract Highlights • A hybrid architecture is proposed to assemble different system combination models. • The architecture is influenced by both statistical and neural network based system combination techniques. • The training datasets are prepared by using different types of MT systems. [ABSTRACT FROM AUTHOR]

A Geographical Indication (GI) is expected to facilitate agri-environmental management in agricultural landscapes. Currently, local products from small-scale farms and national branded products with a relatively large scale of production are being registered using GI schemes. Considering the relationships among GI products, their agricultural landscapes, and traditional ecological knowledge (TEK), as a GI case study, we examined small GI farms in Odate City, Akita Prefecture, Japan, which produce edible plants called Tonburi. This research explored the complex cause-effect relationship between TEK and landscapes and found that the TEK of Tonburi production influenced biological diversity and vice versa. The TEK and skills of small farmers were confined to the family members of each farmer and were not shared at the community level until GI registration. However, the farmers shared their TEK of sustainable agricultural landscape management through the process of GI registration. Through negotiation between local agricultural cooperatives and farmers, TEK was provided as a form of cultural capital and shared with new producers after GI registration. We concluded that enclosed TEK negatively affects production maintenance and landscape management in the long term. However, the GI registration process contributes to the sharing of TEK as a form of cultural capital among Tonburi farmers. • GI registration contributes to sharing of traditional knowledge as a form of cultural capital among Tonburi farmers. • Cultural capital and natural capital are intertwined in a cause-effect relationship, with the GI scheme as a catalyst. • Region-specific variations in cause-effect relationships are related to biophysical conditions and agricultural management. [ABSTRACT FROM AUTHOR]

Based on semi-structured interviews with 54 distinct actors in the UK and Canada, we identify a range of internal psychological orientations that are common (albeit to varying degrees) in both case study regions that, when taken together, provide a lens through which on-farm decisions relating to pro-environmental behaviours are internally analysed and subsequently operationalised. We label these orientations as Production, Business, Environmental, Lifestyle , and Farm Health. Through these orientations, we find farmers are often becoming 'accidental environmentalists' by undertaking many pro-environmental activities for non-environmental reasons. Prominent examples include adopting environmentally beneficial on-farm decisions to support field sports (i.e. shooting), pursuing production improvements with environmental spin-offs (e.g. cover crops, beneficial pollinators), or seeking improvements to personal or family health and well-being (e.g. reduced use of chemicals). This analysis therefore highlights the importance of not oversimplifying farmer motivations along a dualistic profit-seeking v stewardship divide when it comes to understanding environmental behaviour. • We explore farmers' pro-environmental decision-making in England and Ontario, Canada. • We identify a range of internal orientations that are common in both case study regions. • These orientations are Production, Business, Environmental, Lifestyle, and Farm Health. • These interests form a frame through which options are internally analysed and decisions derived. • Farmers are undertaking many pro-environmental activities for non-environmental reasons. [ABSTRACT FROM AUTHOR]