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Atmospheric polycyclic aromatic hydrocarbons (PAHs) are in high levels in developing countries like India. However, limited measurements are inadequate for better understanding of their ambient levels and health effects. This study predicted PAHs concentrations in atmosphere and estimated their sources and health risks in India in four representative months of winter, pre-monsoon, monsoon and post-monsoon in 2015 using an updated version of the Community Multiscale Air Quality model (CMAQ). Predicted PAHs were in agreement with observations from literature. Surface 16-PAHs were highest in winter, with a peak value of 2.5 μg/m

A method preserving cyber-physical systems to operate safely in a joint physical space is presented. It comprises the model-based development of the control software and simulators for the continuous physical environment as well as proving the models for spatial and real-time properties. The corresponding toolchain is based on the model-based engineering tool Reactive Blocks and the spatial model checker BeSpaceD. The real-time constraints to be kept by the controller are proven using the model checker UPPAAL.

Uncertainty analysis is performed to qualify the uncertainty of the infinite multiplication factor (kinf) and nuclide number density induced by cross sections, fission yields and decay half-life in ENDF/B-VIII.0. The SUNDEW code, initially developed for burnup sensitivity and uncertainty analysis with respect to cross sections based on the generalized perturbation theory, is extended to consider fission yields and decay half-life. The Bayesian/general least-squares method is adopted to generate the covariance matrix of fission yields. TMI-1 PWR pin cell given in the UAM project is calculated by SUNDEW. In addition to kinf, the uncertainty of the number densities of various nuclides important for different aspects are calculated and analyzed, including nuclides involved in burnup credit, nuclides used for burnup measurement, and 135Xe. Main conclusions are that the cross section covariances in ENDF/B-VIII.0 can induce larger uncertainty to kinf than ENDF/B-VII.1; the fission yields and decay half-life have obvious contributions for the uncertainty of nuclide number density in some cases.

Dry and wet deposition of sulfur and nitrogen contained air pollutants lead to increase of sulfur and nitrogen to the surface, causing acidification of surface water bodies and subsequent damage to aquatic and terrestrial ecosystems. Louisiana has abundant water resources and it is important to protect water resources from excessive atmospheric deposition of sulfur and nitrogen. However, the information for understanding sulfur and nitrogen deposition and adverse effects in Louisiana is limited. In this study, a source-oriented version of the Community Multi-scale Air Quality (CMAQ) model was used to simulate emission, formation, transport, and deposition of sulfur and nitrogen species in Louisiana in August 2011 to understand the forms and quantities of sulfur and nitrogen deposition due to wet and dry processes in Louisiana, to show the spatial and temporal variations of deposition fluxes, and to quantify the contributions of different sources to sulfur and nitrogen deposition. Aerosol phase sulfate (AeroSO4) has the highest monthly total flux of 6 kg S/ha in wet deposition of sulfur. Major forms of sulfur dry depositions are AeroSO4 (~1 kg S/ha) and SO2 (~3 kg S/ha). Nitrogen deposition is mainly in forms of NO2, HNO3, NH3, and aerosol phase nitrate (AeroNO3). Electric generating utilities (EGU) are the largest contributor to sulfur depositions with monthly total flux of 1.6 kg S/ha, followed by industry (1 kg S/ha) and upwind sources. On-road vehicles and industry are important to nitrogen (except ammonia) depositions with maximum contributions of 0.6 kg N/ha and 0.8 kg N/ha, respectively. The dominate source of ammonia is “Other” implicit sector including agricultural activities.

In wire electrical discharge machining (WEDM), the phenomena of wire electrode going back and hysteresis will appear when servo feed speed does not match the achievable material removal rate, and it is injurious to machining efficiency and accuracy in practical machining process. This study presents a thermal model for predicting the optimal servo feed speed during multi-pulse discharge process. Firstly, the effects of servo feed speed on the practical cutting speed and discharge state are analyzed to define the optimal servo feed speed. Additionally, based on previous thermal model and considering the latent heat of evaporation, a modified thermal model is established to obtain discharge crater size in single pulse discharge process, and this modified model is proved to be with higher precision than other thermal models in previous researches. Then, on the basis of single pulse discharge thermal model, a thermal model is developed to acquire achievable material removal rate in multi-pulse discharge process, and verified experiment data shows that the predicted achievable material removal rate agrees well with the optimal servo feed speed. Eventually, according to the results of cutting experiment under different servo feed speeds, it can be found that the optimal servo feed speed can simultaneously obtain the faster practical cutting speed and the narrower kerf width than those under the other servo feed speeds.

Fiberglass-doped polypropylene (PP) and fiberglass-doped acrylonitrile butadiene styrene (ABS) are more difficult to be laser transmission welded than other pure plastic because of its low laser transmittance, and this paper aims to quantificationally investigate the relationships of welding parameters, molten pool area and shear strength in welding fiberglass-doped PP and fiberglass-doped ABS by simulation and experiment method. Firstly, comparing with previous researches, several technique difficulties in this welding experiment are pointed out. Secondly, a new hybrid heat source model is proposed to build three-dimensional finite element model for predicting temperature distribution and molten pool geometrical size by coupling Rotary-Gauss body heat source and Gauss plane heat source. Then, a group of taguchi experiment is completed to obtain the characteristics of welded joint, and to evaluate the precision of hybrid heat source model under various welding parameters. Furthermore, the mathematic relationships between molten pool area, laser energy per unit of area and shear strength are fitted out to search optimal welding parameter. Eventually, microstructure observation and fracture appearance analysis experiments are implemented to reveal the root cause of above relationships. This proposed hybrid heat source model and mathematical relationships exhibit commendable value for guiding practical production of laser transmission welding.

The regional-to-synoptic-scale steering atmospheric circulation is important for advecting energy, mass, and momentum across space, with the near-surface wind being the local manifestation of this circulation. The local winds can affect phenomena of economic, ecological, and/or aesthetic values, such as bird migrations and prescribed burns to restore bird habitats. The purpose of this research is to classify the days from 1979 to 2018 based on circulation patterns near the surface (i.e., 1000-hPa) and at the highest level of airflow affecting bird migration (i.e., 700-hPa), across the Gulf Coast region of the United States. The resulting patterns, derived from Ward's clustering method on rotated principal component scores, are used as input in a fire management plan to restore niches for bird species such as black and yellow rails and mottled ducks. Results suggest that for the (near-surface) 1000-hPa level, a classification system consisting of eight circulation types maximizes the between-group variability while minimizing the within-group variability, with a total of 95.8 percent of the dataset variance explained, and reasonable correspondence with existing manual, subjective and semi-automated techniques. At the 700-hPa level, a system of eight circulation types was derived, explaining 95.05 percent of the dataset variance. In general, the western U.S. Gulf of Mexico arc is more likely than the eastern to respond to synoptic control in the form of weather types, while the eastern region may have more influence from local-to-meso-scale land and sea breezes. These results will assist in optimizing the success of controlled burn conditions while enhancing efforts to minimize advection to populated areas.

The latest CENDL and ENDF/B evaluated nuclear data libraries was released in 2020 and 2018, respectively. To apply CENDL-3.2 and ENDF/B-VIII.0 in the reactor physic simulations of pressurized water reactor (PWR), the CNP-1000 PWR, which is an improved GEN-II PWR and operated in Fuqing Nuclear Power Plant in China, is simulated using these two libraries. The key parameters during the startup physics tests and power operation in the first three fuel cycles of the CNP-1000 reactor have been simulated and compared with corresponding measurement values. The numerical results show that ENDF/B-VIII.0 performs better in several parameters of the startup physics tests than ENDF/B-VII.0; the cross-section data in CENDL-3.2 is competent in the engineering application of PWR.

Particulate matter with aerodynamic diameter < 2.5 μm (PM2.5) chemical composition data from the Speciation Trends Network (STN) site located in Baton Rouge, Louisiana were analyzed using the receptor Positive Matrix Factorization (PMF) model version 5.0. The PM2.5 samples were collected every third day from January 2009 to December 2014. Seven sources were identified, including secondary sulfate, secondary nitrate, industrial emissions, traffic, crustal dust, road dust and sea salt. The contributions of these seven sources to PM2.5 total mass were 38.4%, 17.6%, 18.7%, 11.5%, 6.1%, 4.2% and 3.6%, respectively. Secondary sulfate, industrial emissions and secondary nitrate were the top three sources. The contributions of industrial emissions and crustal dust have been rising in recent years while that of traffic and sea salt were decreasing. Secondary sources were higher than primary sources during the winter. The crustal and road dust were dominant during the summer, while traffic was more significant during the fall compared to other seasons. During summer, traffic emission and crustal dust were driven by northeast-north winds, traffic is also driven by northeast-north winds in winter, while industry emissions and sea salt were driven by prevailing west and northwest winds during other seasons. PM mass clearly showed the synergetic effects of local sources and distance sources. Thus, measurements and strategies should focus on not only local sources, but also regional transport. Attention should also be paid to industrial and traffic sources since they also account for secondary sources in addition to the primary contributions.

Polycyclic aromatic hydrocarbons (PAHs) in the environment are of significant concerns due to their high toxicity to human health. PAHs measurements at limited air quality monitoring stations alone are insufficient to gain a complete understanding of ambient levels and public exposure of PAHs in China. This study simulated the concentrations of PAHs in China, identified the source contributions, and estimated the health risks. Anthropogenic emissions of 16 priority PAHs directly associated with health risks were generated from the global high-resolution PKU-FUEL-2007 inventory. Open biomass burning emissions were generated from the Fire Inventory from NCAR (FINN). PAHs concentrations in January, April, July, and October 2013 were simulated using the Community Multiscale Air Quality (CMAQ) model after incorporation of chemistry, partitioning, and deposition of PAHs. Predicted PAHs were in good agreement with seasonal and annual averaged observations from previous studies. The surface concentrations of 16-PAHs were higher in winter, with population weight average of 0.8 μg/m3 and peak value of 2.0 μg/m3 in urban areas in the North China Plain (NCP) and the Yangtze River Delta (YRD). Summer and spring exhibited lower concentrations of approximately 0.2 μg/m3 in most areas. The most important sources to PAHs were biomass burning and coal combustion in winter and industrial processes and oil and gas activities in summer. The cancer risk due to inhalation exposure of naphthalene (NAPH) and seven carcinogenic PAHs was significant, with the incremental lifetime cancer risk (ILCR) of >5 × 10−4 in many urban and industrial areas. Exposure to PAHs was estimated to result in 15,198 excess lifetime cancer cases in China. Oil and gas burning associated with transport, residential and commercial activities were major contributors to ILCR in China. Coal combustion was predominant in Shanxi but less important in other regions.

Many cyber-physical systems operate together with others and with humans in a joint physical space. Because of their operation in proximity to humans, they have to operate according to very high safety standards. This chapter presents a method for developing the control software of cyber-physical systems. The method is model-based and assists engineers with spatial and real-time property verification. In particular, the authors describe a toolchain consisting of the model-based development toolset Reactive Blocks, the spatial analyzer BeSpaceD in conjunction with the real-time model checkers UPPAAL and PRISM. The combination of these tools makes it possible to create models of the control software and, if necessary, simulators for the actual system behavior with Reactive Blocks. These models can then be checked for various correctness properties using the analysis tools. If all properties are fulfilled, Reactive Blocks transforms the models automatically into executable code.

A method preserving cyber-physical systems to operate safely in a joint physical space is presented. It comprises the model-based development of the control software and simulators for the continuous physical environment as well as proving the models for spatial and real-time properties. The corresponding toolchain is based on the model-based engineering tool Reactive Blocks and the spatial model checker BeSpaceD. The real-time constraints to be kept by the controller are proven using the model checker UPPAAL.

A method for measuring the channel size of microfluidic chip by using optical coherence tomography (OCT) is investigated. Based on spectral-domain OCT imaging and image processing, an OCT system for measurement of the microfluidic channel size is developed, which is suitable for planar two-dimensional measurement. The cross-sectional images of the micro-channel of a microfluidic chip are obtained by using OCT continuous B-scan technology. With image processing for the acquired image in noise elimination and dispersion compensation, the size of the micro-channels in depth is achieved. Comparing with the single-scan OCT imaging mode, back-passing multiple-scans mode has the capability of high image quality to achieve high measurement precision of micro-channel size.

In this paper, the method of recognition and superposition of sub-pixel shifting in digital holograms is investigated. A group of non-scanning holograms is recognized and superposed by using sub-pixel shifting algorithm. Further, spatio-temporal scanning holograms with sub-pixel displacement are recognized and superposed to further improve imaging resolution by combining spatio-temporal scanning digital holography with sub-pixel shifting algorithm. The experimental results verify the feasibility of improving resolution with sub-pixel displacement.

Recovery of biomass and biodiversity of forest understory vegetation after fire disturbance has been widely studied; however, how this relationship changes and what are the determinants at different post-fire stages in larch boreal forests are still unclear. We investigated a chronosequence of 81 understory plots in larch boreal forests that were disturbed by fires in 1987 (S5), 1992 (S4), 1996 (S3), 2002 (S2), or 2007 (S1). Analysis of variance was conducted to test the differences of biodiversity and biomass among various post-fire stages. Different regression models were used to fit the relationship between biomass and biodiversity, while factors influencing this relationship were identified by boosted regression tree analysis. Results showed that total understory biomass increased from 2.51 t ha−1 in S1 to 8.47 t ha−1 in S3 and declined to 5 t ha−1 in S5. Similar dynamics were also found between species richness and species diversity. Positive linear correlations linked biomass and biodiversit...

SUMMARYBased on product of exponentials (POE) formula, three explicit error models are given in this paper for kinematic calibration of serial robot through measuring its end-effector positions. To obtain these error models, the tool frame should be chosen as reference frame at first, and then each position–error-related segment in the error models using pose measurement should be selected. And during kinematic parameter identification, all the errors in joint twists are identifiable, and the initial transformation errors and the joint zero-position errors can be identified conditionally. Namely, the initial transformation errors are identifiable if they do not contain orientation errors. And the joint zero-position errors are identifiable when a robot only consists of prismatic joints and the coordinates of its joint twists are linearly independent.The effectiveness of this calibration method has been validated by simulations and experiments. The results show that: (1) the identification algorithms are robust and practical. (2) The method of position measurement is superior to that of pose measurement.

Using probabilities in the formal-methods-based development of safety-critical software has quickened interests in academia and industry. We address this area by our model-driven engineering method for reactive systems SPACE and its tool-set Reactive Blocks that provide an extension to support the modeling and verification of real-time behaviors. The approach facilitates the composition of system models from reusable building blocks as well as the verification of functional and real-time properties and the automatic generation of Java code. In this paper, we describe the extension of the tool-set to enable the modeling and verification of probabilistic real-time system behavior with the focus on spatial properties that ensure system safety. In particular, we incorporate descriptions of probabilistic behavior into our Reactive Blocks models and integrate the model checker PRISM which allows to verify that a real-time system satisfies certain safety properties with a given probability. Moreover, we consider the spatial implication of probabilistic system specifications by integrating the spatial verification tool BeSpaceD and give an automatic approach to translate system specifications to the input languages of PRISM and BeSpaceD. The approach is highlighted by an example., In Proceedings FESCA 2014, arXiv:1404.0436

Particulate matter with aerodynamic diameter2.5μm (PM

During the manufacturing of pharmaceutical compounds, solvent mixtures are commonly used, where the addition of a cosolvent allows for the tuning of the intermolecular interactions present in the system. Here we demonstrate how a similar effect can be accomplished using a room temperature ionic liquid. The pharmaceutical compound acetaminophen is studied in 21 common ionic liquids composed of a 1-n-alkyl-3-methylimidazolium cation with 1 of 7 anions. Using the acetate anion, we predict a large enhancement in solubility of acetaminophen relative to water. We show how this is caused by a synergistic effect of favorable interactions between the ionic liquid and the phenyl, hydroxyl and amide groups of acetaminophen, demonstrating how the ionic liquid cation and anion may be chosen to preferentially solvate different functional groups of complex pharmaceutical compounds. Additionally, while the use of charge scaling in ionic liquid force fields has previously been found to have a minute effect on ionic liquid structural properties, we find it appreciably affects the computed solvation free energy of acetaminophen, which in turn affects the predicted solubility.

We propose a model-driven development approach for autonomous control systems with emphasis on the physical space and the communication via wireless connections. In particular, we combine model-based engineering with simulation and emulation techniques for mobile communication. The design and implementation is done using our Reactive Blocks Framework. For the mobile communication we use the popular IEEE 802.11 WLAN protocol which is simulated using software tools in order to get estimations of connection delays. The spatial constraints are verified with our Be Spaced tool. As an example, we present the design and verification of autonomous robots performing services in a large factory hall and coordinating by means of wireless communication which is based on several access points.

The development and analysis of embedded real-time system is complex due to its platform and application dependencies. To tackle this complexity, we amended the model-based engineering method SPACE to enable also the modeling, simulation and verification of real-time properties of reactive systems. In this paper, we present a further extension making performance estimations and schedulability analysis of reactive real-time building blocks possible. First, a performance profile for evaluating real-time tasks of a building block is outlined. Second, we present the schedulability analysis of a high level real-time system which is carried out by transforming real-time interface descriptions to timed automata that are composed with automata simulating hardware and scheduling policies.

SPACE is a model-driven engineering technique for reactive distributed systems. It enables to develop system models from reusable building blocks, formal analysis by model checking as well as automated transformation to executable code. In this paper, we describe an extension of the SPACE formalism which allows to model and verify also real-time behavior. In particular, one specifies real-time constraints in the interface descriptions of the building blocks, so-called Real-Time External State-Machines (RTESMs). The RTESMs are translated to guards, clocks and invariants of Timed Automata which can be analyzed by means of the model checker UPPAAL. The approach is explained by a component protecting an electrical motor controller system against overspeed. In particular, we prove that by keeping certain maximum response times, this system guarantees that the speed of the motor stays within certain limits.

We present a Model-Driven method to develop collaborative systems. In our method, we use UML collaborations to capture the requirements and architecture of such a system. The system behavior is specified by two choreography models: an abstract flow-global and a more detailed flow-localized choreography. These choreography models are both described by UML activity diagrams. A graph-based transformation approach carrying out the transformation from the flow-global to the flow-local choreography is the core contribution of this paper. Our approach is illustrated using a case study of the European Rail Traffic Management System (ERTMS).

Flat belt widely used in many industrial applications suffers from axial motion when the centrelines of the rollers are not perfectly parallel. To reveal the relation between the belt axial motion and the angular misalignment of rollers, an analytic model for researching the belt axial motion in a 2-rollers flat belt system was first proposed, considered the internal mechanical feedback in endless belt. The belt axial motion was described by using a set of delay differential equations. The responses of the belt under varied angular misalignments of two rollers were solved by using fourth-order Runge-Kutta method. The results showed that when the angular misalignment of rollers was suddenly changed, the belt might exhibit a steady motion after an evanescent transitional state stage. Further, the close-form axial velocity of the belt in the steady state stage was deduced. In the steady state stage, the belt could move to the side in which the center distance of two rollers was smaller. The magnitude of the belt axial velocity was approximately in direct proportion to the absolute value of angular misalignment of rollers. It seemed that the direction of the driving roller rotation did not affect the direction of the belt axial motion.

Organisational interoperability requires a matching of goals and provided and required services between interacting organizations. It is being shown that the recent OMG standards BMM and SoaML can be used by business people to reach this agreement, as well as serve as a foundation for describing the realization of interoperability through cross organisational business processes and further realization of IT support with semantic and technical service interoperability. We illustrate the approach with an example of service identification from the Norwegian national Health ICT architecture.