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Independent object 3D motion estimation is a fundamental problem in 3D computer vision. Directly segmenting and estimating rigid object 3D motion from a consistent video frame is an ill-posed problem. We present a self-supervised framework for segmenting moving independent rigid objects and estimating their motion information including location, driving direction, and speed from a monocular video. Specifically, we first estimate depth, optical flow, and camera pose between a pair of video frames, and then synthesize a new 3D viewpoint from this pair. Subsequently, the Motion Recurrent All-Pairs Field Transforms (MRAFT) module is introduced to extract 3D scene flow and a motion area binary mask from a pair of images and depth. After that, a Rigid Object Motion Estimation Module (ROMEM) with a slot attention mechanism is proposed to extract rigid object motion masks from a multi-layer motion field, including optical flow, depth changes, refined scene flow, and motion masks. Finally, 2D images and 3D scene reconstruction errors are used to facilitate self-supervised training for rigid object motion. Experiments on the FlyingThings3D and KITTI datasets demonstrate that our method outperforms other advanced algorithms in estimating depth, optical flow, scene flow, and rigid moving object masks, demonstrating the benefits of our approach. • A self-supervised framework is proposed to extract rigid object motion from video. • Unify multi-modal within a framework to reconstruct dynamic three- dimensional scenes. • Design a MRAFT module to extract scene flow and potential motion binary mask. • The ROMEM module is proposed to extract motion from multi-modal inputs by slot attention mechanism. [ABSTRACT FROM AUTHOR]

• Clogging of microchannel was investigated with NaCl salting-out process. • The respective anti-clogging effect of ultrasound and segmented flow was compared. • A novel strategy utilizing ultrasound-driven slug dredge microchannel was proposed. • Three oscillating slug-induced dredging modes was proposed. • An efficient aspirin recrystallization process was realized. A novel anti-clogging strategy by combining ultrasound and segmented flow was proposed and successfully applied to continuous crystallization process. The individual anti-clogging effect of ultrasound and segmented flow was first investigated, finding that both strategies only slow down the fouling process, but not capable of breaking the clogged solid sediment. As for the combining strategy, segmented slug/bubble was driven to oscillate intensely with ultrasound and dredge the fouled microchannel through three different mechanisms. Not only the long-term operation of microreactor system was guaranteed, but also the necessary energy input was reduced by 1–2 orders of magnitude compared to individual ultrasound. Finally, the ultrasound-driven oscillating slug/bubble was utilized for recrystallization of aspirin. Under E v 0.54–2.60 J/mL, a product yield of 53 %-72 % (equilibrium yield 72 %) was obtained with aspirin average size in the range of 7.84–32.01 μm. The synergistic strategy can be well generalized to various crystallization process once properly designed. [ABSTRACT FROM AUTHOR]

To alleviate the environmental pressure caused by enteromorpha (EP) and improve the efficiency of inhibiting spontaneous combustion of coal, attapulgite (ATP) was combined with EP to prepare an enteromorpha-based composite inhibitor (EPH-ATP). The effect of adding different substances on the surface morphology of the synthesized inhibitor was investigated using scanning electron microscopy (SEM). The effects of three inhibitors (enteromorpha hydrogel (EPH), ATP, and EPH-ATP) were analyzed using thermal analysis kinetics and in situ fourier transform infrared spectroscopy (FTIR). The results showed that the addition of ATP had little effect on the apparent morphology and was uniformly distributed in EPH. At heating rates of 5.0, 10.0, 15.0, and 20.0 K/min, it was found that the degree of the completion of spontaneous combustion of coal was directly related to the heating rate, and coal was more likely to react at low heating rates. In addition, during the combustion and decomposition stage, the average activation energy of coal samples treated with EPH-ATP increased by 306%, which greatly improved the reaction difficulty of the spontaneous combustion of coal. According to the changes in the functional groups with temperature, the in situ infrared process was divided into three stages of slow reaction, violent reaction and stable reaction for the first time. Moreover, the mechanism of EPH-ATP reducing the intensity of reaction by scavenging free radicals was clarified. The results show that the enteromorpha-based composite inhibitor has a good inhibitory effect, realizes the sustainable use of EP, and provides a new scientific basis for the prevention and control of the spontaneous combustion of coal. • An EP-based antioxidant type compound inhibitor was prepared. • Resource utilization of EP was realized. • Thermodynamic characteristics of composite inhibitor were studied. • Reaction mechanism of compound inhibitor in scavenging free radicals was studied. [ABSTRACT FROM AUTHOR]

Abstract: We report the easy synthesis of porous graphene nanosheets (PGNs) using the etching of graphene sheets by MnO2. An electrode made from PGNs exhibits a specific capacitance of 154Fg−1 at 500mVs−1 in 6M KOH compared to a value of 67Fg−1 for graphene nanosheets, and a low capacitance loss of 12% after 5000cycles. Interestingly, PGN electrode material shows an excellent rate capability due to its open layered and mesopore structures that facilitate the efficient access of electrolytes to the electrode material and shorten the ion diffusion pathway through the porous sheets. This approach offers the potential for cost-effective, environmentally friendly and large-scale production of PGNs. [Copyright &y& Elsevier]

• The effects of both μ c and μ d on slug flow are investigated. • The slug flow occurrence is predicted based on composite dimensionless numbers. • For squeezing regime, the droplet scaling law is different from the classical theory. • The film thickness increased more rapidly with Ca D than in gas–liquid slug flow. • Correlations were proposed to reflect the effect of recirculations in both phases on the pressure drop. The hydrodynamics of liquid–liquid slug flow with various fluid systems were investigated, aiming at revealing the viscous effects of both phases. The operation range, droplet formation, film thickness and pressure drop of slug flow were studied and discussed. The results reveal the importance of inertia and viscous forces of both phases in the transition of flow patterns. Accordingly, a universal flow map based on composite terms of Ca c Re c 0.5 and Ca d Re d 0.5 was adopted, which worked well for a wide viscosity range. For droplet formation in the present system, both the squeezing and shearing regimes deviated from the classical ideal models. Under higher capillary number, the film was accumulated at the corners and lateral planes, leading to distinct droplet shapes from literature. For the two-phase pressure drop, new empirical correlations were proposed to describe the recirculation inside both the droplets and slugs. The findings can provide better guidance for optimized reactor design. [ABSTRACT FROM AUTHOR]

• The mass transfer was locally characterized using a colorimetric method. • The effect of fluid rheology on the mass transfer was highly related to the flow rate. • A mass transfer model has been built for the non-Newtonian fluids. • The contribution of the film in mass transfer was highlighted in non-Newtonian fluids. The paper presents a study on the mass transfer of Taylor bubbles flowing in non-Newtonian fluids (slug flow) using an oxygen-sensitive colorimetric method, for the bubble formation and flow stages. The effects of fluid rheology on the operation range, bubble length and bubble shape are first presented, showing that they can be well described by the effective viscosity. The concentration distribution and k L a are also altered by the fluid rheology. Such effect highly depends on the flow rates, leading to distinct phenomena under small and high flow rates. Nevertheless, for all the fluid systems the mass transfer can be described by three parts, the transfer through the caps, through the lateral film and the film-slug exchange. A mass transfer model is proposed accordingly, which shows a larger contribution of the film (20%-60%) in shear-thinning fluids than that in the Newtonian fluid (10%-25%). [ABSTRACT FROM AUTHOR]

The actual use of models and decision tools for real-world reservoir operations is limited due to the gap between the models/tools and the real-world practices, tedious amount of work in case-by-case model developments, and computational difficulty of running complex numerical models. This paper presents generic diagnostic reservoir operation tools (DROT). The tools are developed based on generic properties derived from analytical optimization studies and data mining procedures. Instead of establishing a numerical model, DROT users can apply particular properties and/or procedures to diagnose a specific reservoir operation problem by just providing required inputs. DROT is available online and also provides auxiliary tools such as a data retrieval tool and a data visualization tool. DROT provides an open software framework that can include additional generic tools of models, algorithms, and functions. DROT can be used by reservoir operators, researchers, and students to obtain diagnostic information for the operation of a reservoir. • Analytical studies on reservoir operation are implemented as generic online tools. • A data mining algorithm is realized for revealing real-world operations. • Auxiliary tools for data retrieval and data visualization are developed with DROT. • DROT provides diagnostic information for reservoir operations. • DROT presents a software framework to include additional generic tools. [ABSTRACT FROM AUTHOR]

• HM-DT is proposed to derive a limited number of representative operation modules. • Dynamic operation patterns are identified under changing operation conditions. • Seasonality and non-stationarity of reservoir operation patterns are observed. • Operation behaviors in response to floods and droughts are identified. • Derived reservoir operation modules can be built into hydrological models. Reservoirs have been widely used to regulate streamflow to meet both human and natural water requirements. This study applies a hidden Markov-decision tree (HM-DT) model to derive representative reservoir operation modules under various operation conditions (i.e., inflow, storage, as well as unknown factors) and their transitions (the dynamic change of operation rules) that reflect the impacts of seasonality, long-term non-stationarity, and extreme events on reservoir operation. The representative operation modules can be applied to reservoirs in the same region that are not observed; the capability for simulating dynamic operation behaviors improves the predictive accuracy as compared to regular decision trees. Using a number of reservoirs located in the same region for training, the HM-DT model can derive a limited number of representative operation modules in the form of decision trees (DT), and the transitions between different operation schemes in response to changing operation conditions. The application of the HM-DT model is demonstrated through a case study of the Upper Colorado River basin, where eight representative operation modules are determined for 50 reservoirs located in the region, and the modules are validated with 11 reservoirs in the same region. The eight operation modules are classified into three types (i.e. nearly constant release, release as a piece-wise function of inflow, and release almost identical to inflow). The identified operation modules and the transition patterns between operation modules can be used to better understand real-world operation behaviors, improve future operations, and build realistic reservoir operation components in basin-scale hydrological models. [ABSTRACT FROM AUTHOR]

Understanding how public and research view biofuel development, especially the unsynchronized views, can explain the gaps between the actual biofuel production and consumption and the government mandates in the US. Applying a comparative text mining technique, these views are explored using 9924 news articles and 57,849 research abstracts. It is found both the public and research communities respond actively to major policy and incentive programs and market conditions and the public has been closely following important research advances. However, research and practice should be coordinated to achieve economies of scale for regular and alternative biofuels. Priority is particularly needed for policy research to support legislation and enforcement and remove technical barriers to commercialization; meanwhile, greater attention is needed to prompt the commercialization of mature technologies. In addition, sentiment analysis shows positive public perceptions in general and negative perceptions primarily stemming from fraud in biofuel tax-credit programs with minor concerns on unintended negative impacts of biofuel development and policy implementation issues. This study contributes to methodology by using cutting-edge text-mining techniques to the largest and most up-to-date datasets of public news articles and research publication abstracts so as to compare public and academic views on biofuel development. This study also contributes to knowledge discovery by providing new perspectives on biofuel development, which will support policy design and identify future research directions. Image 1 • Public and academia views on biofuel development are identified and compared. • Both communities respond actively to major policy programs and market conditions. • High public interests exist with innovations in feedstocks and genetic engineering. • Policy research is needed to support legislation and enforcement. • Negative perceptions primarily stem from fraud in biofuel tax-credit programs. [ABSTRACT FROM AUTHOR]

• GDROM is formed with a small set of modules and their application conditions. • GDROM has a consistent and transparent structure simulating daily operation dynamics. • GDROM is tested with 467 reservoirs with various operation purposes in CONUS. • GDROM outperforms a tradition decision tree model in daily storage simulation. This study presents a generic data-driven reservoir operation model (GDROM). The hidden Markov-decision tree (HM-DT) is applied to deriving representative operation modules for a reservoir; a classification and regression tree (CART) algorithm is used to identify the application and transition conditions for the operation modules. These two procedures result in the GDROM that is featured by 1) using a few input variables (inflow, storage, DOY, and PDSI); 2) inheriting merits of decision trees but dramatically reducing model complexity; 3) adopting a consistent and transparent structure (i.e., better interpretability than other machine learning models); and 4) showing a better performance than traditional decision tree models, especially in storage simulation. GDROM is developed for 467 reservoirs with diverse operation purposes in different regions of the Contiguous United States (CONUS), and the testing procedure shows comparable accuracy in release simulation to other ML models; among these reservoirs, 15 are selected for detailed analysis with diverse operational purposes and regulation capacities, from different USGS Water Regions. GDROM presents a ready-to-use reservoir operation model that can be incorporated into a watershed hydrological simulation model. [ABSTRACT FROM AUTHOR]

Groundwater is the major source of water for Tamarix chinensis growth in the Yellow River Delta (YRD) region, and the groundwater depth (GWD) dramatically influences the physiological activities of T. chinensis. The quantitative response of the photosynthetic physiological process of T. chinensis to the GWD in freshwater habitats remains unclear. In this study, the response characteristics of gas exchange parameters in the leaves of three-year-old T. chinensis seedlings were measured and analyzed at a graded series of seven GWDs (0 m, 0.3 m, 0.6 m, 0.9 m, 1.2 m, 1.5 m and 1.8 m). The GWD thresholds corresponding to drastic changes in the photosynthetic efficiency and the GWDs of several levels of photosynthetic productivity and efficiency were also determined. In the freshwater habitats of the YRD, variations in GWD significantly altered the relative soil water content (RSWC) and thus influenced the photosynthetic efficiency of T. chinensis. RSWC at 0 ≤ GWD ≤ 0.9 m and GWD at 1.2 m ≤ GWD ≤ 1.8 m directly influenced the photosynthetic physiology of T. chinensis. When the GWD was 1.2 m, net photosynthetic rate (P n), apparent quantum efficiency and water use efficiency (WUE) values all peaked. Thus, T. chinensis exhibited a high light and water use efficiency, wide ecological amplitude in terms of light, and high photosynthetic capacity. The optimum GWD for photosynthetic carbon assimilation and WUE in T. chinensis was determined to be 1.2 m. At a deep (≥1.64 m) or shallow (≤0.53 m) GWD, both P n and WUE in T. chinensis clearly decreased below the corresponding mean values. The main causes for the reduction in P n in these two GWD ranges (≤0.53 m, ≥1.64 m) were stomatal and nonstomatal limitations, respectively. Additionally, a moderate GWD of 1.09–1.25 m corresponded to the "high-productivity and high-efficiency GWD" range , in which T. chinensis displayed a high photosynthetic yield and WUE. Overall, the photosynthetic capacity of T. chinensis shows characteristics of high tolerance to moderate GWDs from 1.09 m to 1.25 m but intolerance at both shallow (≤0.53 m) and deep (≥1.64 m) GWDs in freshwater habitats. Unlabelled Image • Photosynthetic efficiency of T. chinensis showed obvious threshold response to groundwater depths; • Stomatal limitation at 0≤GWD≤1.5 m and non-stomatal limitation at 1.5 m≤GWD≤1.8 m were the main restriction mechanism of P n. • RSWC at 0≤GWD≤0.9 m and GWD at 1.2 m≤GWD≤1.8 m were the direct factor influencing photosynthetic physiological process of T. chinensis. • 1.2 m was the optimum groundwater depth for photosynthesis of T. chinensis. • Photosynthetic capacity of T. chinensis was high tolerant to medium GWD from 1.09 m to 1.25 m but intolerant to both low GWD (≤0.53 m) and high GWD (≥1.64 m). [ABSTRACT FROM AUTHOR]

While understanding individual stakeholders' perspectives on the adoption and conversion to a biofuel-based landscape has been a subject of many previous studies on biofuels, there has been relatively little attention given to understanding how the interaction between multiple stakeholders involved in biofuel development could influence the widespread adoption of biofuel production. This paper analyzes the key stakeholder interactions utilizing various data sources including survey results, social media posts, and empirical and theoretical analyses. An intensive review is conducted for a number of surveys and research papers on different aspects of biofuel development such as land use choices, biorefinery and transportation, infrastructure development, consumer priorities, environmental impacts, etc. Following that, a stakeholder synergy approach is applied to synthesizing typical responses of stakeholders, such as producers, consumers, biorefineries, rural communities, and the government, and discussing how their responses influence each other's decisions and the overall system performance. Based on the findings of inadequate stakeholder synergy, it is recommended that new surveys and further research should be conducted to understand why synergy between stakeholders in biofuel development is absent. Additionally, this paper provides research perspectives, including (1) applying cutting-edge text-mining techniques to conduct sentiment analysis, and research and public attention analysis; (2) using an agent-based model to simulate stakeholder interactions and understand the factors that influence stakeholder synergy and the emergence of a bioeconomy. • A stakeholder synergy approach to analyzing cellulosic biofuel development in the United States. • Identified preferences, barriers, and opportunities of multiple stakeholders involved in biofuel production and consumption. • Suggested research efforts to explore and quantify stakeholder synergy for the bioeconomy. [ABSTRACT FROM AUTHOR]

• The effect of fluid viscosity on liquid-liquid mass transfer was studied. • Several local transfer patterns were observed at both straight channels and bends. • Ka and K can increase with the increase in μ C at large flow rates. • Three mass transfer regimes were identified and correlated to local transfer patterns. Mass transfer characteristics of liquid-liquid Taylor flow with various fluid pairs are investigated, in order to reveal the viscous effects of the fluids. The concentration pattern in continuous slugs, mass transfer time and mass transfer coefficient are discussed and analyzed. Several different concentration patterns originated from recirculation are observed at both straight channels and curved bends, respectively. It is shown that the mass transfer coefficient (Ka and K) can increase with the increase in the viscosity of the continuous phase at large flow rates, which is explained by the increased contribution of the film at the lateral droplet side and its exchange with the bulk slug. Based on the dominance of different parts (i.e. , film, cap), three mass transfer regimes are distinguished. Correlations for each regime, which covers a wide range of fluid viscosity of 0.89–45.6 mPa·s, are developed to predict the mass transfer coefficient. [ABSTRACT FROM AUTHOR]

The emergence of the cellulosic bioeconomy requires not only adequate technological, economic, and policy advances, but also effective communication and coordination among the multiple stakeholders in the bioeconomy community. Aiming to facilitate stakeholder communication and collaboration for cellulosic bioeconomy growth, an agent-based model is developed as a community communication tool in this study. The tool simulates the behaviors and interactions of key stakeholders, as well as the responses and interactions between the stakeholders and biophysical, socioeconomic, and environmental conditions. The agent behavior rules are developed and validated based on behavior and economic theories and information attained from a stakeholder focus group study and a land use survey. A pilot study in a Central Illinois watershed shows stakeholder synergies, i.e., positive feedback loops across multiple stakeholders. The modeling tool's role in facilitating community communication is demonstrated via the focus group study. A comparison of policy scenarios suggests that the cellulosic bioeconomy development is fastest under a portfolio of policies combining the views of the multiple stakeholders. Critically, subsidy for small-scale bio-facilities is essential as it rapidly initializes an early market for cellulosic feedstocks and the adoption of Miscanthus. The communication tool is applied to bringing stakeholders and researchers together to develop shared visions, assess barriers, and explore solution portfolios to initialize and speed up the regional cellulosic bioeconomy. • Agent-based model presents a communication tool for cellulosic bioeconomy community. • The model is validated with mixed theoretical knowledge and survey data. • Stakeholder synergies enabling cellulosic bioeconomy emergence are identified. • A shared vision among stakeholders is illustrated via the communication tool. • Subsidies for small-scale bio-facilities effectively promote cellulosic bioeconomy. [ABSTRACT FROM AUTHOR]

Abstract: Graphene nanosheet (GNS)/Co3O4 composite has been rapidly synthesized by microwave-assisted method. Field emission scanning electron microscopy and transmission electron microscopy observation reveals the homogeneous distribution of Co3O4 nanoparticles (3–5nm in size) on graphene sheets. Electrochemical properties are characterized by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. A maximum specific capacitance of 243.2Fg−1 has been obtained at a scan rate of 10mVs−1 in 6M KOH aqueous solution for GNS/Co3O4 composite. Furthermore, the composite exhibits excellent long cycle life along with ∼95.6% specific capacitance retained after 2000 cycle tests. [ABSTRACT FROM AUTHOR]

• The hydrodynamics, mixing and mass transfer of two-phase processes are reviewed. • Bubble/droplet formation mechanism and scaling models are summarized. • The dynamic behavior during formation stage is highlighted. • The circulation topology and mixing inside both droplets and slugs are discussed. • The interfacial mass transfer regimes and simulative models are presented. Microreaction technology is preferential in process intensification and chemical synthesis, especially in multiphase applications. A thorough understanding of the hydrodynamics and mass transfer is the pre-requisite for implementing such applications. This review discusses the recent progress on the flow and mass transfer of two-phase systems in microchannels, in a multi-scale view from local mechanism to global behavior. The flow patterns, the formation of bubbles/droplets, and the manipulation of bubbles/droplets are presented and discussed in detail. The mass transfer aspects include the velocity profile and mixing inside droplets/slugs, as well as the interfacial mass transfer mechanism and simulative models. The aim of the review is to show directly the physical ingredients which determine the transport phenomena, help explain the observed behavior, and guide reactor design. To simplify the physical ingredients, the attention is focused on straight channels while phenomena in other channels (e.g. , meandering channel) are neglected. [ABSTRACT FROM AUTHOR]