Search

Understanding the spatial distribution of schistosome infection is critical for tailoring preventive measures to control and eliminate schistosomiasis. This study used spatial analysis to determine risk factors that may impact Schistosoma japonicum infection and predict risk in Hunan and Jiangxi Provinces in the People's Republic of China. The study employed survey data collected in Hunan and Jiangxi in 2016. Independent variable data were obtained from publicly available sources. Bayesian-based geostatistics was used to build models with covariate fixed effects and spatial random effects to identify factors associated with the spatial distribution of infection. Prevalence of schistosomiasis was higher in Hunan (12.8%) than Jiangxi (2.6%). Spatial distribution of schistosomiasis varied at pixel level (0.1 × 0.1 km), and was significantly associated with distance to nearest waterbody (km, β = −1.158; 95% credible interval [CrI]: −2.104, −0.116) in Hunan and temperature (°C, β = −4.359; 95% CrI: −9.641, −0.055) in Jiangxi. The spatial distribution of schistosomiasis in Hunan and Jiangxi varied substantially and was significantly associated with distance to nearest waterbody. Prevalence of schistosomiasis decreased with increasing distance to nearest waterbody in Hunan, indicating that schistosomiasis control should target individuals in close proximity to open water sources as they are at highest risk of infection. [ABSTRACT FROM AUTHOR]

This paper proposes fault tolerant operation strategies for three-level neutral point clamped pulsewidth modulation inverters in high power, safety-critical applications. Likely faults are identified and fault tolerant schemes based on the inherent redundancy of voltage vectors are presented. Simulation verification is performed to show fault handling capabilities. Prototyping and principle investigation are performed on a 150-KW inverter and testing results are presented. Index Terms--Fault tolerant, neutral-point-clamped (NPC) inverter, pulsewidth modulation (PWM), three-level inverter.

A large quantity of Steel Balls Automatic precise Counting device is introduced in this paper. Inductance sensors are used for ball detection and STC15F2K60S2 microprocessor is used to do the signal processing. When steel balls are sent to the PVC pipe at the same time, some balls will connect together because of the collision. The sensor will send a connected signal instead of multiple signals if it meets the connected balls. This could cause counting mistake of the device. A correction method is used to solve this problem. The device setup angle could be gotten by using dual sensors to get the average moving speed of the steel balls according to the fixed relations between the setup angle and the speed, which is not affected by whether the steel balls overlap or not because it used two voltage Jump edge to judge the start and end moment of timer. After that, the device setup angle is used to get the standard moving time to single sensor according to the known function relationship. The counting numbers are corrected by using the standard duration to compare with each recording low voltage duration passing single sensor. This method solves the counting mistake problem when a lot of steel balls are pushed into the PVC pipe together. The device improves the efficiency and accuracy of the ball counting. [ABSTRACT FROM AUTHOR]

This paper investigates the control problem for a quadrotor with a cable-suspended payload (QCSP). A new adaptive control strategy is designed to control the velocity of a volumetric payload with unknown mass in the presence of rotor downwash. The asymptotic stability of the resulting closed-loop system is analysed via the Lyapunov method. Furthermore, a novel structure is designed to suspend the payload on the quadrotor by a cable, and a gyroscope is installed on this structure to measure the payload's swing angle. The designed controller's performance is demonstrated by simulations implemented in a Simulink/SimMechanics environment. The effectiveness of the proposed control scheme is validated in real experiments. [ABSTRACT FROM AUTHOR]

Rational and purposeful designs of amorphous materials with desirable structures are difficult to implement due to the complex and unordered nature of such materials. In this work, a modelling algorithm was proposed for amorphous covalent triazine-based polymers to construct atomistic representative models that can reproduce the experimentally measured properties of experimental samples. The constructed models were examined through comparisons of simulated and experimental properties, such as surface area, pore volume, and structure factor, and further validated by the good consistency observed among these properties. To assess the predictive capability of the modelling algorithm, we used a new covalent triazine-based polymer and predicted its porosity by constructing a simulated model. The predicted results on the surface area and pore volume of the simulated model were quantitatively consistent with the experimental data derived from the experimentally synthesized sample. This consistency reveals the predictive capacity of the proposed modelling algorithm. The algorithm could be a promising approach to predict and develop advanced covalent triazine-based polymers for multiple applications. [ABSTRACT FROM AUTHOR]

Based on core data, microphotographs, well-logging and test analysis, etc., combined with regional geological data, the characteristics of mixed rocks in oil group I of the upper third member of the Paleogone Shahejie Formation in the Dawangzhuang area, Raoyang Sag, Bohai Bay Basin, were studied. The sedimentary environment was analyzed, and the sedimentary model was explored. The study shows that the mixed rocks may be divided into two categories: siliciclastic carbonate rocks and carbonate siliciclastic rocks. Mainly sandy dolomite and calcareous sandstone occur in the Dawangzhuang area, with mainly siliciclastic carbonate rocks in the central and northern areas, and carbonate siliciclastic rocks in the west and south. The genetic types of mixed sedimentation are dominated by facies mixing in the early and middle stage of oil group I of the upper third member of the Paleogone Shahejie Formation oil group, and by in situ mixing in the early stage of oil group I of the upper third member of the Paleogone Shahejie Formation oil group. A few cases of source mixing were found in the late stage of oil group I of the upper third member of the Paleogone Shahejie Formation oil group in the study area. The sedimentary environment of the mixed sedimentation of carbonates is mainly shore-shallow lake in the Dawangzhuang area, classified into three kinds of mixed deposits: sandstone bar microfacies, carbonate bar microfacies, and muddy shore-shallow lake microfacies. A comprehensive analysis of the effect of lake level variation on mixed deposition, together with tectonic evolution and paleogeo-morphology, revealed a sedimentary model of mixed rocks during steadily rising, then falling, lake levels. When the lake level was slowly rising, the mixed deposits characterized by both facies mixing and in situ mixing gradually increased. When the lake level was suitable, the content of pure carbonate rocks increased and facies mixing decreased. Later, when the lake level was falling, source mixing was evident. [ABSTRACT FROM AUTHOR]

Impurity is an important factor that can affect significantly turbulent transport in tokamaks. In order to study the impurity physics, we implement a new impurity module in the gyrokinetic particle simulation code GTC (Gyrokinetic Toroidal Code). With an improved numerical scheme, we expand the validity of gyrokinetic Poisson equation in the GTC to the short wavelength region, for both non-zonal and zonal parts of the perturbed Poisson equation. Verifications of this new scheme are carried out on the linear instability and zonal flow response. The linear simulation of the ion temperature gradient (ITG) instability including the impurity ions shows that the new Poisson solver can obtain the correct linear growth rate and frequency at the thermal ion gyro-radius scale. The residual zonal flow with impurities obtained via the new zonal flow solver is consistent with the numerical and analytical predictions in the large aspect-ratio limit. The nonlinear simulation of the ITG turbulence shows that the turbulent transport is significantly reduced by the impurity ions through decreasing the linear growth rate of the instability. [ABSTRACT FROM AUTHOR]

Wearable electronics have attracted a wide range of attention with various functions due to the development of semiconductor industry and information technology. This work focuses on a triboelectric nanogenerator-based self-charging power system as a continuous energy source for wearable electronics. The triboelectric nanogenerator has a multilayer elastomeric structure with closely stacked arches as basic functional units. Owing to material and structural innovations, this triboelectric nanogenerator performs outstanding electric output with the maximum volume charge density ≈0.055 C m−3 and practical properties for energy harvesting from body motions. Utilizing the triboelectric nanogenerator as outsole to harvest energy from walking or jogging, a pair of shoes is fabricated with the maximum equivalent charge current of each shoe being around 16.2 µA and specific fitness functions realized on each shoe separately without complex connections. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) has been considered to be a more effective technology to harvest various types of mechanic vibration energies such as wind energy, water energy in the blue energy, and so on. Considering the vast energy from the blue oceans, harvesting of the water energy has attracted huge attention. There are two major types of 'mechanical' water energy, water wave energy in random direction and water flow kinetic energy. However, although the most reported TENG can be used to efficiently harvest one type of water energy, to simultaneously collect two or more types of such energy still remains challenging. In this work, two different freestanding, multifunctional TENGs are successfully developed that can be used to harvest three types of energies including water waves, air flowing, and water flowing. These two new TENGs designed in accordance with the same freestanding model yield the output voltages of 490 and ≈100 V with short circuit currents of 24 and 2.7 µA, respectively, when operated at a rotation frequency of 200 rpm and the movement frequency of 3 Hz. Moreover, the developed multifunctional TENG can also be explored as a self-powered speed sensor of wind by correlating the short-circuit current with the wind speed. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have been invented as a new technology for harvesting mechanical energy, with enormous advantages. One of the major themes in their development is the improvement of the power output, which is fundamentally determined by the triboelectric charge density. Besides the demonstrated physical surface engineering methods to enhance this density, chemical surface functionalization to modify the surface potential could be a more effective and direct approach. In this paper, we introduced the method of using self-assembled monolayers (SAMs) to functionalize surfaces for the enhancement of TENGs' output. By using thiol molecules with different head groups to functionalize Au surfaces, the influence of head groups on both the surface potential and the triboelectric charge density was systematically studied, which reveals their direct correlation. With amine as the head group, the TENG's output power is enhanced by ∼4 times. By using silane-SAMs with an amine head group to modify the silica surface, this approach is also demonstrated for insulating triboelectric layers in TENGs. This research provides an important route for the future research on improving TENGs' output through materials optimization. [ABSTRACT FROM AUTHOR]

ABSTRACT Blends of polycarbonate (PC) and acrylonitrile -ethylene-propylene-diene-styrene (AES) were reactive compatibilized by styrene-maleic anhydride copolymers (SMA). The changes in phase morphology and interfacial characteristics of the blends as a function of maleic anhydride content of SMA and the concentration of compatibilizer have been systematic studied. The occurrence of reaction between the terminal hydroxyl groups of PC and the maleic anhydride (MA) of compatibilizer was confirmed by fourier transform infrared (FTIR) spectroscopy. A glass transition temperature ( Tg) with an intermediate value between Tg(AES) and Tg(PC) was found on differential scanning calorimeter (DSC) curves of PC/AES blends compatibilized with SMA contains high levels of MA. Furthermore, at lower compatibilizer content, increase of the compatibilizer level in blends result in decreasing gap between two Tgs corresponding to the constituent polymers. Small angle X-ray scattering (SAXS) test results indicated that compatibilizer concentration for the minimum of blend interface layer's thickness was exactly the same as it was when compatibilized PC/AES blend exhibited optimal compatibility in DSC test. The observed morphological changes were consistent well with the DSC and SAXS test results. A new mechanism of interfacial structural development was proposed to explain unusual phenomena of SMA compatibilized PC/AES blends. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42103. [ABSTRACT FROM AUTHOR]

Panum's limiting case generally refers to the phenomenon that two features presented to one eye and a single feature presented to the other are combined and then perceived as two features at different depths. It is still not clear why experimental results derived from the Panum-type configuration (all lines parallel) support a double fusion viewpoint, but they do not for the Wheatstone-type configuration (one line not parallel to the others). Some experimental results support the double fusion theory, while others do not, even under a small disparity. Here we report that, under a small disparity, when the vertical gradients of the horizontal disparity of dichoptic feature pairs in previous Wheatstone-type configurations were increased or decreased, the evidence which was considered to be very convincing in previous studies, either supporting or against the double fusion viewpoint, was challenged, and even turned to support the opposite view. Moreover, it was discovered that changes in the way features were arranged altered the results. Together, these results indicate that double fusion is the common basis for all kinds of Panum-type configurations. But for the Wheatstone-type configurations double fusion is also constrained by the vertical gradient of disparity of the configurations in addition to disparity and influenced by the degree of similarity/conflict between binocular cues and monocular cues resulting from different arrangements of features. [ABSTRACT FROM AUTHOR]

The electronic nose is the olfactory organ of the robot, which is composed of a large number of sensors to perceive the smell of objects through free diffusion. Traditionally, it is difficult to realize the active perception function, and it is difficult to meet the requirements of small size, low cost, and quick response that robots require. In order to address these issues, a novel electronic nose with active perception was designed and an ensemble learning method was proposed to distinguish the smell of different objects. An array of three MQ303 semiconductor gas sensors and an electrochemical sensor DART-2-Fe5 were used to construct the novel electronic nose, and the proposed ensemble learning method with four algorithms realized the active odor perception function. The experiment results verified that the accuracy of the active odor perception can reach more than 90%, even though it used 30% training data. The novel electronic nose with active perception based on the ensemble learning method can improve the efficiency and accuracy of odor data collection and olfactory perception. [ABSTRACT FROM AUTHOR]

The exponential increase in the number of genomes deposited in public databases can help us gain a more holistic understanding of the phylogeny and epidemiology of Klebsiella pneumoniae. However, inferring the evolutionary relationships of K. pneumoniae based on big genomic data is challenging for existing methods. In this study, core genes of K. pneumoniae were determined and analysed in terms of differences in GC content, mutation rate, size, and potential functions. We then developed a stable genes-based method for big data analysis and compared it with existing methods. Our new method achieved a higher resolution phylogenetic analysis of K. pneumoniae. Using this genes-based method, we explored global phylogenetic relationships based on a public database of nearly 953 genomes. The results provide useful information to facilitate the phylogenetic and epidemiological analysis of K. pneumoniae , and the findings are relevant for security applications. • The core genome of Klebsiella pneumoniae comprises 3018 genes. • A genes-based method was developed for phylogenetic analysis of big data sets. • Surveillance of CG258 and hyper-virulent lineages facilitated. • The findings are relevant for security applications of K. pneumoniae. [ABSTRACT FROM AUTHOR]