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A recent study predicts that by 2025, up to 75 billion internet of things (IoT) devices will be connected to the internet, in which data sharing is increasingly needed by massive IoT applications as a major driver of the IoT market. However, how to meet the interests of all participants in complex multi-party interactive data sharing while providing secure data control and management is the main challenge in building an IoT data sharing ecosystem. In this article, the authors propose a blockchain-empowered data sharing architecture that supports secure data monitoring and manageability in complex multi-party interactions of IoT systems. First, to build trust among different data sharing parties, the authors apply blockchain technologies to IoT data sharing. In particular, on-chain/off-chain collaboration and sharding consensus process are used to improve the efficiency and scalability of the large-scale blockchain-empowered data sharing systems. In order to encourage IoT parties to actively participate in the construction of shared ecology, the authors use an iterative double auction mechanism in the proposed architecture to maximize the social welfare of all parties as a case-study. Finally, simulation results show that the proposed incentive algorithm can optimize data allocations for each party and maximize the social welfare while protecting the privacy of all parties.

In this paper, the design and operation of a novel coal-fired circulating fluidized bed (CFB) drum boiler that can generate superheated steam using saline water were introduced. The natural circulation water dynamics with a drum was adopted instead of the traditional once-through steam generator (OTSG) design, so that superheated steam can be generated for the better performance of the steam assisted gravity drainage (SAGD) technology in heavy oil recovery. The optimized staged evaporation method was proposed to further decrease the salinity of water in the clean water section of the boiler. The evaporating pipes of the salted water section were rearranged in the back pass of the boiler, where the heat load is low, to further improve the heat transfer safety. A CFB combustion technology was used for coal firing to achieve a uniform heat transfer condition with low heat flux. Pollutant control technologies were adopted to reduce pollutant emissions. Based on the field test, the recommended water standard for the coal-fired CFB drum boilers was determined. With the present technology, the treated recovery wastewater can be reused in steam-injection boilers to generate superheated steam. The engineering applications show that the boiler efficiency is higher than 90%, the blowdown rate is limited within 5.5%, and the superheat of steam can reach up to 30 K. Besides, the heavy oil recovery efficiency is significantly improved. Moreover, the pollutant emissions of SO2, NOx and dust are controlled within the ranges of 20–90 mg/(N·m3), 30–90 mg/(N·m3)and 2–10 mg/(N·m3) respectively.

The soot formation and distribution in coal jet flames were measured using Laser-Induced Incandescence (LII) technique over a wide range of coal mass concentration (Ccoal). Experiments were conduct...

The classification performance of model coal mill classifiers with different bottom incoming flow inlets was experimentally and numerically studied. The flow field adjacent to two neighboring impeller blades was measured using the particle image velocimetry technique. The results showed that the flow field adjacent to two neighboring blades with the swirling inlet was significantly different from that with the non-swirling inlet. With the swirling inlet, there was a vortex located between two neighboring blades, while with the non-swirling inlet, the vortex was attached to the blade tip. The vorticity of the vortex with the non-swirling inlet was much lower than that with the swirling inlet. The classifier with the non-swirling inlet demonstrated a larger cut size than that with the swirling inlet when the impeller was stationary (~ 0 r⋅min-1). As the impeller rotational speed increased, the cut size of the cases with non-swirling and swirling inlets both decreased, and the one with the non-swirling inlet decreased more dramatically. The values of the cut size of the two classifiers were close to each other at a high impeller rotational speed (≥ 120 r⋅min-1). The overall separation efficiency of the classifier with the non-swirling inlet was lower than that with the swirling inlet, and monotonically increased as the impeller rotational speed increased. With the swirling inlet, the overall separation efficiency first increased with the impeller rotational speed and then decreased when the rotational speed was above 120 r⋅min-1, and the variation trend of the separation efficiency was more moderate. As the initial particle concentration increased, the cut sizes of both swirling and non-swirling inlet cases decreased first and then barely changed. At a low initial particle concentration (

Large eddy simulation (LES) has become a promising tool for pulverized coal combustion with the development of computational fluid dynamics (CFD) technologies in recent years. LES can better capture the unsteady features and turbulent structures of coal jet flame than Reynolds averaged Navier Stokes (RANS). The coal-fired power plants in China are now required to be operated in a wide load range and quickly respond to the electric grid. The boiler performance of variable loads should be evaluated in terms of flow, heat transfer, and combustion processes. In this paper, LES was applied to simulate a 660 MW ultra-supercritical boiler under BMCR (boiler maximum continue rate), 75%THA-100, and 50%THA-100 conditions. The predicted gas velocities agree well with the thermal calculation and the temperature error is less than 130 K. The simulation results show that the operation load has significant effects on the boiler performance. It is also proved that LES can provide guidance for the design and operation of advanced coal-fired boilers.

Background Hirschsprung’s disease (HSCR) is an enteric nervous system birth defect partially caused by a genetic disorder. Single‐nucleotide polymorphisms (SNPs) of the cytochrome P450 family 2 subfamily B member 6 (CYP2B6) gene are reported to be associated with HSCR. Methods We evaluated the association of rs2054675, rs707265, and rs1042389 with HSCR susceptibility in southern Chinese children including 1470 HSCR patients and 1473 controls using the TaqMan SNP Genotyping Assay. Results rs2054675 C allele and the rs707265 G allele were risk SNPs for total colonic aganglionosis (OR = 1.82, 95% CI 1.29 ~ 2.55, P_adj < 0.001 and OR = 0.68, 95% CI 0.48 ~ 0.97, P_adj = 0.034). These results suggested that CYP2B6 rs2054675 and rs707265 polymorphisms were associated with increased susceptibility to the severe HSCR subtype in southern Chinese children. Conclusion We suggest that CYP2B6 rs2054675 and rs707265 polymorphisms are associated with increased susceptibility to the severe HSCR subtype in southern Chinese children., Hirschsprung's disease (HSCR) is an enteric nervous system birth defect partially caused by a genetic disorder. Single‐nucleotide polymorphisms (SNPs) of the cytochrome P450 family 2 subfamily B member 6 (CYP2B6) gene are reported to be associated with HSCR. We evaluated the association of rs2054675, rs707265 and rs1042389 with HSCR susceptibility in southern Chinese children including 1470 HSCR patients and 1473 controls. rs2054675 C allele and the rs707265 G allele were risk SNPs for total colonic aganglionosis (TCA) (OR = 1.82, 95% CI 1.29 ~ 2.55, P_adj

Hirschsprung disease (HSCR) is an infrequent congenital intestinal dysplasia. The known genetic variations are unable to fully explain the pathogenesis of HSCR. The α/β‐hydratase domain 1 (ABHD1) interferes with the proliferation and migration of intestinal stem cells. Docking protein 6 (DOK6) is involved in neurodevelopment through RET signalling pathway. We examined the association of ABHD1 and DOK6 genetic variants with HSCR using 1470 controls and 1473 HSCR patients from Southern Chinese children. The results clarified that DOK6 rs12968648 G allele significantly increased HSCR susceptibility, in the allelic model (p = 0.034; OR = 1.12, 95%CI = 1.01~1.24) and the dominant model (p = 0.038; OR = 1.12, 95%CI = 1.01~1.25). Clinical stratification analysis showed that rs12968648 G allele was associated with increased risk of short‐segment HSCR (S‐HSCR), in the allelic model (p = 0.028; OR = 1.14, 95%CI = 1.01~1.28) and the additive model (p = 0.030; OR = 1.14, 95%CI = 1.01~1.28). ABHD1 rs2304678 C allele had higher risk to develop total colonic aganglionosis (TCA) in the allelic model (p = 7.04E‐03; OR = 1.67, 95%CI = 1.15~2.43) and the dominant model (p = 4.12E‐03; OR = 1.93, 95%CI = 1.23~3.04). DOK6 rs12968648 and ABHD1 rs2304678 had significant intergenic synergistic effect according to logical regression (p = 0.0081; OR = 0.76, 95%CI = 0.63~0.93) and multifactor dimensionality reduction (MDR, p = 0.0045; OR = 1.25, 95%CI = 1.07~1.46). This study verified two susceptible variations of HSCR on ABHD1 and DOK6. Their roles in HSCR should be conducted in further studies.

Numerical simulation of pulverized coal combustion with the large eddy simulation (LES) method can provides important instructions on the design optimization of boilers. Because of its huge computational cost, a simple but reliable NOx prediction model is required in LES. Through the air-staged combustion experiments of six kinds of coals which conducted in an electric heated down-fired furnace (DFF), the relationship between NOx reduction and CO + H2 generation in the fuel-rich zone was identified. Based on this observation, a semi-empirical modeling strategy was proposed: instead of CHi which is difficult to calculate, the concentration of CO + H2 is used to quantify NO homogeneous reduction. An integrated NOx prediction model was proposed and implemented into LES simulation. The results proved the new model can accurately predict different NOx evolution characteristics under various conditions. Furthermore, the comparison indicated the LES method performs better on NOx prediction than the RANS method, especially in the area where the turbulent fluctuation is relatively stronger.

While the power plant units are the developing towards larger capacity, the relative shortage in thermal efficiency of the circulating fluidized bed (CFB) boiler unit, which has obtained significant development in recent years, is becoming more and more apparent. However, the thermal efficiency computational model applied for different CFB boiler units are not derived yet. Based on Generalized Energy Efficiency Distribution Matrix (GEEDM) model which is designed for normal pulverized coal boiler units, this paper innovatively built a computational model of cycle efficiency for CFB boiler units. Moreover, the mathematical influences of main local influencing factors like terminal difference, extraction steam pressure loss, heat loss, drained water cooling insufficient, steam desuperheater, shaft seal leakage of steam turbine and connection schemes of ash cooler to this model were further proposed to strengthen its industrial applications. In the meanwhile, the detailed thermodynamic analysis of a 660 MW ultra-supercritical unit in China was studied to provide some optimized design and operation suggestions. Particularly, for this unit, an optimized connection scheme of the ash cooler, a core component in the CFB boiler to reclaim physical heat in the bottom ash, was selected from 20 different connection schemes.

Soot plays an essential role in radiative heat transfer in pulverized coal boilers, but the controlling processes that cause different soot behaviors in O2/N2 and O2/CO2 atmospheres are not clear. ...

BACKGROUND: Vascular geometry may play an important role in the development of atherosclerosis. This study aimed to investigate the relationships between the geometrical characteristics of basilar artery (BA) and the presence, burden, and distribution of BA plaques using magnetic resonance vessel wall imaging. METHODS: Patients with cerebrovascular symptoms in the posterior circulation were recruited and underwent magnetic resonance imaging. The BA’s geometrical characteristics, including actual length, straightened length, tortuosity, lateral basilar artery-vertebral artery (VA) angle, lateral mid-BA angle, and BA convexity, were measured. The presence of plaques, stenosis, and plaque burden, including mean and maximal wall thickness, were evaluated. The BA’s cross-sectional vessel wall was divided into 4 quadrants: dorsal, ventral, right, and left quadrant. The distribution of BA plaques was analyzed. RESULTS: Of 344 recruited patients (mean age: 68.1±11.1 years; 200 males), 100 (29.1%) had BA plaques. Patients with BA plaques had higher tortuosity of the BA (13.6±9.0 vs. 9.7±7.7, P

Purpose: To compare diagnostic accuracy of cTTE, cTCD and TEE in patients undergoing patent foramen ovale closure (PFO) so as to provide evidence for clinical decision-making.Methods: The clinical data of 140 patients with cerebral infarction or migraine who successfully underwent PFO closure or whose right cardiac catheterization results showed no PFO in our hospital were analyzed retrospectively, including clinical baseline, data of cTTE, cTCD and TEE.Results: Patients who successfully underwent PFO closure or whose right cardiac catheterization results showed no PFO were divided into group A and group B, respectively. The differences of the shunt in cTTE and cTCD, the diameter of PFO in TEE and the appearance of bubbles in cTTE were compared. The results showed that the proportion of medium-large shunt in group A was significantly higher than group B in resting cTCD, post-Valsalva cTCD and total cTCD respectively (67.35% VS 42.86%，P=0.004；100% VS 71.42%，P=0.0003；81.63% VS 51.43%，P=0.002). The proportion of medium-large shunt in group A was higher than group B in cTCD (75.90% VS 19.35%，P＜0.001). The diameters of PFO of group A were larger than group B in TEE (2.18±0.78 VS 1.19±0.78，P＜0.001). Take the successful PFO closure as the state variable. The ROC curves of cTTE, cTCD and TEE were made, and the results showed that cTCD and TEE had better sensitivity and specificity. The proportion of appearance of bubbles within 5 cardiac cycles in cTTE in group A was significantly higher than group B (73.47% VS 42.86%，P=0.005).Conclusions: For the patients with PFO to be occluded, the success rate of operation could be improved by selecting patients with larger shunt, larger diameter of foramen ovale and shorter interval in the appearance of bubbles. Otherwise, there was perhaps no PFO. cTCD and TEE had better diagnostic value for PFO closure than that of cTTE.

With the in-depth development of China's education reform, the combination of educational public opinion and emotion analysis is conducive to the discovery of the evolution law of public sentiment and related factors, and provides ideas for the guidance of public opinion of relevant government departments. This paper proposes an analysis model of public opinion on the education policy network based on text mining, obtains network comment contents through Octopus crawler, preprocesses the data, and introduces the calculation formula of emotion heat, on which the evolution process of public opinion is divided into incubation period, outbreak period, spreading period and decline period. Combined with visualization and emotional heat maps of provinces and ages are constructed, so as to grasp the spatial-temporal evolution law of educational public opinions. Taking the postponement of the college entrance examination in 2020 as an example, the empirical analysis proves that the online public opinion analysis model of education policy can reflect the evolution law.

Electrical impedance spectroscopy has long been considered a promising technique for noninvasive, in‐situ root investigation because of its sensitivity to anatomy and physiology. However, the complexity of the root system and its coupling with stem and soil have hindered the signal interpretation and methodological upscaling to field applications. This study addresses these key issues by introducing three‐channel acquisitions and their interpretation through Cole–Cole fitting. This solution could successfully decouple the impedance response of stem, roots, and soil, as well as provide convenient parametrization and comparison of their impedance signals. The methodological solution was tested on 80 wheat (Triticum aestivum L.) and 10 pecan [Carya illinoensis (Wangenh.) K. Koch] plants, the first extensive and field investigation. The investigation provided evidence of (a) proximal current leakage in herbaceous root systems, extending recent laboratory results and previous indirect field studies. (b) Major role of the plant stem, which has been a substantial concern raised in numerous studies. (c) Minor contribution from the soil, addressing the doubts on the comparability of results obtained in different soil conditions. All together, these evidences lead to indirect correlations between impedance signals and root traits. The explored solution is expected to support the adoption of the impedance spectroscopy, in line with the diffusion of multichannel impedance meters and growing interest in root physiology and phenotyping.

Patients with pneumonia-type lung cancer (PTLC) do not exhibit specific clinical features, which makes imaging diagnosis difficult. Therefore, the aetiology of the pathological changes occurring during PTLC remains unclear. The current study aimed to explore the possible mechanism of PTLC formation by CT scans and pathological analysis of the lungs. A retrospective analysis was conducted on the CT and pathological data of 17 cases of PTLC. The diagnosis of lung cancer was confirmed by pathology. The CT scans of nine patients indicated diffuse distribution of lesions in the lungs, whereas those of three patients indicated single-lung multi-leaf distribution, and those of the remaining five patients included single-leaf distribution. All patients demonstrated increased plaque or patchy density in the majority of the lesions located near the heart. The pathological types of the identified tumours were mucinous adenocarcinoma with adherent growth as the main sub-type. A large number of mucus lakes were observed, containing floating tumour cells, as determined by optical microscopy. In addition, a number of tumour cells were located in the residual alveolar wall of the observed mucus lakes. The results of the present study suggested that the mucinous adenocarcinoma tumour cells produced substantial quantities of mucus, and that the cells were scattered and planted along with the mucus through the airway, which led to possible development of pneumonia-type mucinous adenocarcinoma.

We present a new method for efficient high-quality image segmentation of objects and scenes. By analogizing classical computer graphics methods for efficient rendering with over- and undersampling challenges faced in pixel labeling tasks, we develop a unique perspective of image segmentation as a rendering problem. From this vantage, we present the PointRend (Point-based Rendering) neural network module: a module that performs point-based segmentation predictions at adaptively selected locations based on an iterative subdivision algorithm. PointRend can be flexibly applied to both instance and semantic segmentation tasks by building on top of existing state-of-the-art models. While many concrete implementations of the general idea are possible, we show that a simple design already achieves excellent results. Qualitatively, PointRend outputs crisp object boundaries in regions that are over-smoothed by previous methods. Quantitatively, PointRend yields significant gains on COCO and Cityscapes, for both instance and semantic segmentation. PointRend's efficiency enables output resolutions that are otherwise impractical in terms of memory or computation compared to existing approaches. Code has been made available at https://github.com/facebookresearch/detectron2/tree/master/projects/PointRend., Comment: Technical Report

We present Momentum Contrast (MoCo) for unsupervised visual representation learning. From a perspective on contrastive learning as dictionary look-up, we build a dynamic dictionary with a queue and a moving-averaged encoder. This enables building a large and consistent dictionary on-the-fly that facilitates contrastive unsupervised learning. MoCo provides competitive results under the common linear protocol on ImageNet classification. More importantly, the representations learned by MoCo transfer well to downstream tasks. MoCo can outperform its supervised pre-training counterpart in 7 detection/segmentation tasks on PASCAL VOC, COCO, and other datasets, sometimes surpassing it by large margins. This suggests that the gap between unsupervised and supervised representation learning has been largely closed in many vision tasks., Comment: CVPR 2020 camera-ready. Code: https://github.com/facebookresearch/moco

Large eddy simulation (LES) is becoming a promising tool for the design and retrofit of utility boilers. It explicitly calculates the large-scale eddies which play an important role in the particle behavior inside the boilers. An ultra-supercritical tangentially fired boiler was simulated under the boiler maximum continuous rate (BMCR) condition by LES. The particle phase was tracked by the simplified direct quadrature method of moments in the Eulerian framework. Five particle sizes were adopted to represent the wide particle size distribution. The predicted gas velocities were in good agreement with the thermal calculation. The LES results showed that the particles were more likely to be concentrated in the main burner zone while quickly dispersed in the over fire air (OFA) zone. A theoretical analysis found that the particle Stokes number based on the sub-grid scale was much smaller than one. The particles would behave as tracers for the eddies resolved by LES. However, some differences between the small and large particles were observed in the particle number density distributed along the vertical and horizontal directions. It meant that the inertial effects on the particle motion cannot be neglected.

Zhundong (ZD) coalfield has a large number of coal reserves. However, the severe fouling and slagging problems that occurred in ZD coal-fired utility boilers have seriously hindered the large-scale utilization of ZD coal. Deep understanding of the mineral transformation of ZD coal during combustion and its impact on fouling and slagging can provide technical support for fouling and slagging prevention in utility boilers. In this paper, a novel temperature and atmosphere controlling method was proposed to study ash deposition. Wucaiwan (WCW) coal ash samples in different atmospheres and temperatures were collected efficiently by the established single thermocouple high-temperature online microscope observation test rig. The influence of rapid heating and cooling on the mineral transformation of WCW coal ash samples was systematically investigated using XRD and SEM-EDS, respectively. The effects of SO2 in the flue gas on the mineral transformation and the sulphates generation of the coal ash were analysed by comparing the experimental results in oxidizing atmosphere and simulated flue gas atmosphere. The experimental results showed that the microscopic morphology, mineral and element conversion of coal ash samples during heating and cooling were quite different. Compared with oxidizing atmosphere, SO2 in the flue gas significantly increase the S content of ash at 600 °C−1200 °C and the amount of molten minerals on the quenched ash sample surface during cooling. These results indicate that SO2 can promote the sulfation reactions of alkali/alkaline earth metal (AAEM) on the quenched ash sample surface and restrain the decomposition of S-containing minerals in ash cooling. The investigation also reveals that the molten AAEM sulphate on the ash surface is mainly generated at 800 °C−900 °C. The present study not only provides the fundamental understandings of mineral transformation but also guides industrial applications to reduce the risk of ash deposition.

Hydrogen-enriched natural gas is a promising low-carbon fuel in combustion devices. To better assess its feasibility from the extinction prevention point of view, the extinction of near-limit premixed hydrogen-methane/air flames over a wide range of equivalence ratios was measured using the single-flame counterflow configuration. Results showed that the hydrogen addition resulted in a greater extinction stretch rate. Further analysis demonstrated that the extinction stretch rate of premixed hydrogen-methane/air flames linearly correlated with the corresponding reference flame speed. Thereby a combustion regime map diagram, separating the burning and extinction, was sketched. In addition, critical extinction Damkӧhlor number of premixed hydrogen-methane/air flames was investigated and it was found to be insensitive to the hydrogen addition and equivalence ratio. Finally, the hydrogen addition effect and the corresponding extinction response were assessed for two scenarios, 1) constant thermal load (gas turbine, gas-fired boilers, etc.), and 2) constant fuel injection pressure (gas stove, oven, etc.). The results indicated that H2 addition promoted the combustion safety by increasing the extinction stretch rates, but an allowable H2 variation window existed when considering the unexpected high-temperature damage of the burners. The allowable H2 variation window of Scenario 1 was found much broader than that of Scenario 2.

Microbial sulfate reduction occurs ubiquitously in natural environments. In oil and gas reservoirs, the generation of sulfide (also known as souring) can result in the corrosion of steel infrastructure and downgrading of oil quality, among other environmental and health-related concerns. The complex interplay between hydrological, geochemical, and biological processes during souring is poorly understood, preventing effective treatment and mitigation especially in naturally heterogeneous subsurfaces. In this work, three-dimensional flow tank experiments are utilized as a mesoscale experiment that links well-constrained batch and column experiments to field measurements. The mesoscale tank experiment investigating perchlorate treatment of souring is coupled with reactive transport modeling to understand the effects of heterogeneity on souring and effectiveness of perchlorate treatment. Tracer experiments were conducted at the start and end of the experiment to constrain flow pathways and heterogeneities. Is...

Meningioma is one of the most common intracranial tumors. It has the features of benign and slow growing. We focused on the meningioma in the elderly, retrospectively analyzed 528 valid meningioma patients, including 115 (21.8%) patients older than 65 years old. The elderly patients were shown to have significantly larger tumor diameter (mean [±SD] 43.4 ± 18.0 mm) comparing with the young group (mean [±SD] 37.6 ± 16.5 mm, p 0.01). Post-operative KPS was significantly lower in the elderly group (mean [±SD] 79.64 ± 26.37) than the young group (mean [±SD] 88.81 ± 17.36, p 0.01). Multivariate regression of post-operative KPS scales at discharge and 6 months follow-up showed operative complications, pre-operative comorbidities, tumor diameter, and challenging location had a significant impact on the outcome. However, tumor blood supply, Simpson grades, pathology, and pre-operative symptoms were shown to have less impact on the post-operative KPS scale. The outcome for meningioma in elderly patients was affected by factors related more to the safety of the operation than characteristics of the tumor. Therefore, rather than achieving total resection, conservative and safety preferential treatment strategies should be regarded as a higher priority for better quality of life.

Although clothing is a critical factor in assessing human thermal comfort, gender differences exist in thermal responses. This paper presents research on gender differences in adult physiological and psychological responses to the thermal environment, using 12 different clothing ensembles. The experiment was conducted at four air temperatures: 10, 16, 22, and 28 °C, with three different series of clothing ensembles in each air temperature. The main conclusions are as follows: women are more sensitive to a colder thermal environment. Their measured overall skin temperatures were lower than those of their male counterparts and the predicted values for cold environments. This was particularly true in the case of hands, feet, and lower body parts, resulting in women feeling colder than men in the same cold environment. However, there were no significant differences in thermal sensations between the genders when their measured skin temperatures were the same. Different body parts showed different levels of thermal adaption to cold environments: the head, hands, and lower body had lower neutral skin temperatures in cold environments than those recorded in a previous study of a neutral environment, especially in the case of women. Due to these physiological and psychological differences of local body, more men than women preferred to add warmer or additional pants in cold environments. This article provides information to help researchers and designers take gender differences into consideration when designing indoor thermal environments, helping to improve both thermal comfort and system efficiency.

The flame propagation of nanoaluminum cloud in different atmospheres such as CO2, air, and O2 was experimentally studied in a transparent quartz tube. Measurements of the flame length, height, propagation velocity, and temperature indicate that these parameters undergo regular changes in different atmospheres. The maximum measured temperature in CO2 was lower than that in air. On the basis of these results, the flame propagation mechanism of a nanoaluminum cloud is discussed. Scanning electron microscopy revealed that the combustion products consist of uniform spherical particles. On the other hand, the X-ray diffraction analysis indicated the presence of Al, γ-Al2O3, θ-Al2O3, and α-Al2O3 in the combustion products of nanoaluminum cloud in air and the existence of Al, θ-Al2O3, α-Al2O3, and Al2OC when the cloud burns in CO2.

Personal air supply systems (PASSs) have shown great potential in buildings, but to date, the usefulness of PASSs in aircraft cabins in winter has not been examined. In this study, 40 subjects participated in experiments in a model aircraft cabin constructed at Chongqing University. The subjects were exposed to air from a personal air supply at flow rates of 0, 0.5, 1.0, and 1.5 L/s under eight different conditions: 28, 26, 24, and 22 °C while wearing winter clothing (≈1.23 clo); 24, 22, and 20 °C while wearing winter clothing with a jacket (≈1.55 clo); and 26 °C while wearing summer clothing (≈0.65 clo). The results indicate that the subjects were more thermally sensitive to the environment in the aircraft cabin than that in buildings. Because a higher draft rate (DR) at the face occurred under some conditions, a new DR model based on convective heat transfer at the face was constructed. The perceived air quality (PAQ) had a strong relationship with the airflow rate of the air supply and the standard effective temperature, implying that the PAQ is affected by the heat balance of the body. Thus, recommended adjusted thermal environment criteria for a personal air supply while wearing winter clothing that account for the thermal sensation, drafts, and PAQ are presented.

Personal air supply is important for both thermal comfort and air quality for individuals. However, no appropriate airflow rate for a nozzle in aircraft cabins is included in the existing standards. To study the effect of the nozzle air supply on thermal comfort and optimize the airflow rate for a nozzle, both measurements of the air flow field and a human thermal comfort survey were carried out in an experimental three-row aircraft cabin. The experiments used four airflow rates (0 L/s, 0.67 L/s, 0.96 L/s and 1.45 L/s) for a nozzle and three different cabin temperatures (24 °C, 26 °C, 28 °C). The air velocity distribution was obtained to calculate the air velocity for the nozzle jets at any point. This study provides an understanding of the effect of the nozzle air supply on passengers' thermal comfort and the optimal designs for a nozzle air supply system. The nozzle airflow rate for thermal comfort was calculated for a personal air supply at different cabin temperatures. The thermal comfort map for a nozzle can be referenced for the design of a personal air supply system in aircraft cabins.

An experimental research was conducted to study passengers’ responses to the thermal environment when boarded aircraft cabins. The results show that passengers adapted to the thermal environment by behavioral and psychological paths. Before entering into the cabin, the Sick symptom, thermal sensation and thermal discomfort was obviously higher at walking state than waiting state. Subjects’ thermal comfort were achieved by using personal air outlet (PAO) and adjusting clothes. And after enter the aircraft 10 min -15 min, the difference of subjective responses between different pre-states became small, because of actively adaption.

Elderly demand for indoor thermal comfort and energy conservation is increasing in an aging society. To reveal the thermal responses of the elderly in a warm summer environment, a field study involving experimental measurements was conducted in Chongqing, China. The study included 333 subjects in 17 residential buildings and 119 subjects in 6 elderly nursing homes; it showed that elderly persons as passive users of air conditioners preferred cooling by natural ventilation. The mean thermal sensation vote was insensitive and lower than estimates obtained from the PMV model in warm environments. The physiological responses of eight elderly subjects (65 ± 3) were measured in a climate chamber at 18 °C and 34 °C and compared with those from eight college students (22 ± 1) and eight middle-aged subjects (50 ± 5). In this chamber, oral temperature, blood pressure, and heart rate of elderly and middle-aged persons were determined to be almost constant as the air temperature was changed to a hot/cold environment for 30 min, a different result from that of the young subjects. However, the skin temperatures for all age groups showed dependency with air temperature conditions, suggesting skin temperature as an optimal monitoring parameter for the entire population.

As a severe lethal cancer, hepatocellular carcinoma (HCC) usually originates from chronic liver injury and inflammation, in which the discovery of key genes is important for HCC prevention. Here, we analyzed the time serial (from 0 week to 30 weeks) transcriptome data of liver injury samples in diethylnitrosamine (DEN)-induced HCC mouse model. Through expression and function analyses, we identified that Cyp2c29 was a key gene continuously downregulated during liver injury. Overexpression of Cyp2c29 suppressed the NF-κB activation, proinflammatory cytokine production and hepatocyte proliferation by increasing its production 14,15-epoxyeicosatrienoic acid (14,15-EET). Furthermore, in vivo Cyp2c29 protected against liver inflammation in liver injury mice models by reversing the expression on functions of cell proliferation, metabolism and inflammation including suppressing NF-κB pathway and compensatory proliferation. CYP2C8 and CYP2C9, two human homologs of mouse Cyp2c29, were decreased in human HCC progression and positively correlated with HCC patient survival. Therefore, through systematical analysis and verification, we identified that Cyp2c29 is a novel gene in liver injury and inflammation, which may be a potential biomarker for HCC prevention and prognosis.

This paper examines and reports on two new methods, i.e., the Stockwell transform based (ST) method and self-healing cross-correlation (SC) method, in determining the S-wave arrival time fo...

MILD coal combustion is one of promising technologies for clean coal utilization due to uniform heat flux and low NOx emission, while the effect of turbulent mixing on single coal particle combustion under high temperature and low oxygen concentration remains to be studied for micron level particles. In this paper, a 1-D transient coal combustion model was applied to describe mass and heat transfer around a single particle, and the effect of forced convection was modeled to represent turbulent mixing according to similarity analysis. Based on that, effect of particle Reynolds number (Rep) on single coal particle combustion was investigated at various temperature (Ta), oxygen concentration (xO2) and particle diameter (d0). As Rep increases, ignition time (ti) decreases quickly at first and then decreases slowly. ti of larger particle is more sensitive to Rep. As Rep increases, flame temperature (Tf) for 40 μm coal particle decreases, while Tf for 80 μm coal particle barely changes, and that for 160 μm coal particle increases a little. The recommended d0 for MILD coal combustion is smaller than 80 μm. As xO2 decreases from 21% to 5%, ti apparently increases and Tf decreases. ti at lower Ta is more sensitive to Rep. Tf decreases with increasing Rep when Ta < 1200 K. But it appears the opposite trend at Ta = 1600 K. The recommended Ta for MILD coal combustion is lower than 1400 K, while it cannot be too low considering the burnout of char particle.

Non-intrusive load monitoring (NILM) is a core technology for demand response (DR) and energy conservation services. Traditional NILM methods are rarely combined with practical applications, and most studies aim to decompose the whole loads in a household, which leads to low identification accuracy. In this paper, an NILM approach based on multi-feature integrated classification (MFIC) is explored, which combines some non-electrical features such as ON/OFF duration, usage frequency of appliances, and usage period to improve load differentiability. The implementation of MFIC algorithm is consistent with traditional event-based method. The uniqueness of our algorithm is that it designs an event detector based on steady-state segmentation and a linear discriminant classifier group based on multi-feature global similarity. Simulation results using an open-access dataset demonstrate the effectiveness and high accuracy of MFIC algorithm, with the state-of-the-art NILM methods as benchmarks.

For social networks, the interactions among agents and the relative self-confidence of each agent compared with the effects of its neighbors generally change over time. This requires using time-varying signed digraphs to describe the opinion forming processes of agents, where the positive and negative edges can represent cooperations and antagonisms, respectively. In this paper, an improved opinion dynamics model instead of the conventional Laplacian-type model is exploited with allowance of the potential variation of relative self-confidence of each agent, which can be reflected by the diagonal dominance degree. It is shown that both the structural characteristics of social networks and the diagonal dominance degrees determine the opinion forming performances, and some sufficient conditions related to these two factors are proposed to establish the bipartite consensus and stability results of agents. Two simulation examples are provided to illustrate the obtained opinion forming behaviors.

To study the impact of air conditioners (AC) on occupants’ behaviours and comfort, two comparison surveys were conducted during hot summer weather before and after air conditioners were installed in student dormitories at Chongqing University in 2008 and 2016, respectively. The results showed that after the ACs were installed, occupants’ environmental satisfaction vote was notably higher irrespective of whether the equipment was used. The proportion of ACs used (PAU) in 2016 and the proportion of fans used (PFU) in 2008 were logistically fit with the outside temperatures, and these data displayed very similar trends. However, less variety in adaptive behaviours was evident after the ACs were installed. When ACs were used, lower proportions of windows were opened (13%) and higher proportions of occupants felt stuffy (54%), experienced draughts (38%), and reported sick building syndrome (SBS). This study provides scientific insight into the advances and problems caused by the popularization of ACs.

We introduce a new memory architecture, Bayesian Relational Memory (BRM), to improve the generalization ability for semantic visual navigation agents in unseen environments, where an agent is given a semantic target to navigate towards. BRM takes the form of a probabilistic relation graph over semantic entities (e.g., room types), which allows (1) capturing the layout prior from training environments, i.e., prior knowledge, (2) estimating posterior layout at test time, i.e., memory update, and (3) efficient planning for navigation, altogether. We develop a BRM agent consisting of a BRM module for producing sub-goals and a goal-conditioned locomotion module for control. When testing in unseen environments, the BRM agent outperforms baselines that do not explicitly utilize the probabilistic relational memory structure, Comment: Accepted at ICCV 2019

The U.S. Department of Energy's Watershed Function Scientific Focus Area (SFA), centered in the East River, Colorado, generates diverse datasets including hydrological, geological, geochemical, geophysical, ecological, microbiological and remote sensing data. The project has deployed extensive field infrastructure involving hundreds of sensors that measure highly diverse phenomena (e.g. stream and groundwater hydrology, water quality, soil moisture, weather) across the watershed. Data from the sensor network are telemetered and automatically ingested into a queryable database. The data are subsequently quality checked, integrated with the United States Geological Survey's stream monitoring network using a custom data integration broker, and published to a portal with interactive visualizations. The resulting data products are used in a variety of scientific modeling and analytical efforts. This paper describes the SFA's end-to-end infrastructure and services that support the generation of integrated datasets from a watershed sensor network. The development and maintenance of this infrastructure, presents a suite of challenges from practical field logistics to complex data processing, which are addressed through various solutions. In particular, the SFA adopts a holistic view for data collection, assessment and integration, which dramatically improves the products generated, and enables a co-design approach wherein data collection is informed by model results and vice-versa.

At present, my country’s agricultural product logistics is still in its infancy, the agricultural product circulation system is still relatively backward, the agricultural product circulation links are too many, the logistics technology level is low, the logistics cost is high, and the agricultural product circulation information is not smooth. In the context of low-carbon economy, in order to promote the integration of resources in the agricultural product supply chain system, optimize the operation between organizations and make it similar to the internal operation of the organization, and realize the rationalization and maximization of overall benefits, supply chain integration should be used Thought, carry out integrated management of agricultural product logistics, build a supply chain integrated agricultural product logistics model, and promote the integration of agricultural product production links, the integration of circulation links, and the integration of the supply chain of production and circulation links.

A ventilation nozzle’s airflow characteristics could have an influence on a passenger’s thermal comfort and dispersion of pollutants in an aircraft cabin, but there is little published research in this area. In this article, the temperature and air velocity from a nozzle jet were measured in a simulated three-row aircraft cabin at more than 220 points for both isothermal and non-isothermal jets. The non-isothermal jets were tested for air supply temperature differences of ± 5 and 10℃, and the isothermal jets for volume flowrates of 1.86 × 10−7, 2.67 × 10−7, and 4.03 × 10−7 m3/h. The results show that both the nozzle jet’s temperature and air velocity distributions are axially symmetrical and that the decay of the jet is rapid. The equation for the air velocity distribution was used to calculate the air velocity at any point in the main jet region for different volume flowrates. The temperature difference was shown to have little effect on the air velocity distribution for the main region of a nozzle jet, whereas the air flowrate was shown to significantly affect the air velocity distribution. This suggests that the effect of nozzle jet on passenger’s thermal comfort is mostly due to its air velocity distribution rather than temperature distribution.

Oxygen-enriched circulating fluidized bed (CFB) technology is considered as one of the low carbon emission power generation technologies. By recycling the flue gas into the furnace, the CO2 concentration in the exhaust gas can reach over 90%. The coal ignition temperature and ignition characteristics are important factors for boiler design and for choosing the feeding temperature during the transition from air-firing to oxy-firing. The ignition and combustion processes of five types of coal under four different atmospheres (air, O2 27%, O2 40%, O2 53%) were measured in a laboratory scale fluidized bed reactor (FBR) with an under-bed preheat system. Using thermocouples and a gas analyzer, the changes in bed temperature and the concentrations of different components, such as O2, CO2 and CO, in flue gas were directly measured to determine the coal ignition temperature, TiF. It was found that TiF decreases with increasing O2 concentration. At lower bed temperatures, two-stage ignition processes were observed in certain ranges of initial bed temperature and oxygen concentration. The influence of initial bed temperature on volatile release and the SO2 emission in the ignition processes were also discussed.

Zhundong coal is one of the most important coals in China due to its huge reserve, but it causes severe fouling and slagging problems when it is burnt in boilers for its high AAEMs (alkali and alkaline earth metal species) contents. Accurately determination of the occurrence modes and contents of AAEMs in Zhundong coals is a necessary step to overcome the ash-related problems. Nowadays, different researchers used different methods or procedures to determine AAEMs in Zhundong coals, and the data were scattering. Based on a series of experiments on the effects of extraction conditions, an improved extraction method with clearly defined conditions for each extraction step was proposed. 0.1 mol/L NH 4 Cl (pH = 8.5) instead of 1 mol/L NH 4 OAc (pH = 7) was used to extract the exchangeable AAEMs in Zhundong coals to avoid the high solubility of carbonates in the extraction solution. The improved method was more accurate and took much less time than the conventional one. With the proposed extraction method, the occurrence modes and contents of AAEMs in three Zhundong coals were measured. The results revealed that Na is mainly water soluble (Na w /Na total = 50–85%) which is halite or in the form of surface bound Na + , while Ca and Mg are mainly acid soluble (Ca ac /Ca total = 60–90%, Mg ac /Mg total = 45–90%) which are carbonates together with a little amount of sulfates. Exchangeable AAEMs organically bonded to the coal matrix are not the main occurrence mode of AAEMs. Acid insoluble Ca-species could be rankinite. The amounts of AAEMs in the same occurrence mode could be remarkably different among coals from different Zhundong district. The improved sequential extraction method can be extended to determine AAEMs in high carbonate-containing coals.

The TiO 2 @PANI nanobelts were successfully prepared via an in-situ chemical oxidative polymerization method. The structure characterization clearly indicated that PANI could be well wedged with TiO 2 nanobelts. Furthermore, compared with P25, TiO 2 nanobelts and PANI, the photocatalysis of TiO 2 @PANI nanobelts were dramatically improved. And recycling experiments confirmed that the TiO 2 @PANI photocatalysts had excellent stability and cycle performance. In addition, by careful investigation of influence factors, a possible mechanism was proposed.

Moderate or intense low oxygen dilution (MILD) combustion is a promising technology for coal utilization due to the uniform heat flux and low NOx emission. In such coal cloud combustion, it is essential to investigate the effect of surrounding particles on the single coal combustion behaviors. In this work, the effect of particle distance on ignition, volatile flame, soot volume fraction and combustion modes are studied through a 1-D model with Neumann boundary condition. For pulverized coal combustion, heterogeneous ignition is dominating rather than homogeneous ignition. When particle number density is small, the ignition time of coal jet is dominated by that of large particles; while when particle number density is large, the ignition time of coal jet is dominated by that of small particles. According to the transient oxygen distribution at different particle distances, when the particle distance is large, the combustion is diffusion controlled; while when the particle distance is small, the combustion is kinetics controlled. At low oxygen mole fraction, soot emission increases with increasing particle distance because the yields-promoting effect dominates. At high oxygen mole fraction, the consumption-strengthening effect competes with the yields-promoting effect, thus the soot emission increases first and then decreases as particle distance increases. The numerical method in this work is able to predict the combustion modes at different particle number density. At least 90 times of the particle diameter is required for the size of the calculating domain when the Dirichlet boundary condition is used for the modeling of a single coal particle combustion.

To mitigate adverse effects of climate change on agricultural productivity, it is essential to obtain a better understanding of how plant traits influence crop yields and profits. To explore such interactions, we used a coupled ecohydrological and biogeochemical model, ecosys, and applied it to an agricultural farm cultivating wheat in Ardmore, Oklahoma, USA. Our results show that positive impacts of elevated CO2 on winter wheat cannot offset negative influences of warming that shortens grain filling periods and thereby grain content. We found that CO2 fertilization effects were weaker than expected without additional fertilizer addition. To identify conditions that simultaneously optimize wheat yields and profits, we performed model optimization analyses by varying root radius, nutrient transfer conductance, and fertilizer application rates. Optimum conditions were found for root radius in the range 0.1–0.25 mm and nutrient transfer conductance in the range 0.004–0.008 h−1. However, under climate change, an additional 5.6 gN m−2 of fertilizer was required to maximize net profits compared to present-day climate conditions. These optimum conditions led to yield improvements of 38%, 23%, 20%, and 17% under RCP2.6, 4.5, 6.0, and 8.5, respectively, which in turn improved net profits by 98%, 90%, 76%, and 31% compared to baseline, respectively. That is, crop breeding alone may not be sufficient to meet growing food demands without additional N fertilizer applications. However, these higher fertilization application rates lead to increased nitrogen losses as leachate and N2O, motivating analyses on the net radiative balance of these systems and their sensitivity to future climate.

The huge reserve of Zhundong (ZD) coal makes it important for energy utilization of China. However, big concerns on fouling and slagging in pulverized coal-firing boilers were risen due to its high alkali content. It’s important to investigate deposition in different heating surfaces of a boiler burning ZD coal. In this paper, XRF, XRD, ICP-OES were conducted to analyze the properties of ash deposits collected from different heating surfaces in a 350 MW boiler burning 30% Wudong (WD) and 70% Wucaiwan (WCW) coals. Thermodynamics calculations were applied to study the mineral composition of coal ash in the range of 200–1600 °C under different coal co-firing ratio. The analytical results of the ash deposits showed that in medium-temperature (800–1100 °C) flue gas zone (FR and FS), ash deposits have higher sulfate content. While in high temperature flue gas zone (WW and PS), ash deposits have higher Si/Al content and lower S content. The Na/S contents in FR (~1000 °C) are much higher than in other deposits. The thermal equilibrium calculation results showed that a large amount of liquid Na2SO4 and CaSO4 will be generated when burning WCW coal. Co-firing WD and WCW coals can reduce the amount of sulfate (l/slag) formation and the co-firing ratio greatly influence the elimination effect. It can be speculated that not all the sulfates in the ash deposits are formed in flue gas. The sulfation of the Na-containing minerals condensed on the heating surfaces will promote the ash deposition.