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The electric vehicles nowadays are managed by networked controllers. Because of the advantages of fast, reliable, simple wiring, and light weight, CAN bus has become one of the most widely used field buses in the world. Most of the networks were designed with little concern about security which has recently motivated researchers to demonstrate various kinds of attacks against the system. This paper proposes an optimization method for encrypting CAN Messages. In addition, a single frame CAN message can only transmit 64-bit valid data, it is often necessary to complete the communication task by sending a multi-frame message with the same ID. The AES algorithm has become the first choice for encrypting multi-frame CAN messages with its extremely high reliability and fast encryption and decryption speed. In this paper, a method of encrypting multi-frame CAN messages based on the AES algorithm is proposed, and on the basis of which a hash value is optimized to ensure the security of data transmitted on the CAN bus.

We study the private information retrieval (PIR) problem under arbitrary collusion pattern for replicated databases. We find its capacity, which is the same as the capacity of the original PIR problem with the number of databases $N$ replaced by a number $S^*$. The number $S^*$ is the optimal solution to a linear programming problem that is a function of the collusion pattern. Hence, the collusion pattern affects the capacity of the PIR problem only through the number $S^*$., This is a full version of the paper submitted to ISIT 2020

We report the detection of a Saturn-size exoplanet orbiting HD 332231 (TOI 1456) in light curves from the Transiting Exoplanet Survey Satellite (TESS). HD 332231, an F8 dwarf star with a V-band magnitude of 8.56, was observed by TESS in Sectors 14 and 15. We detect a single-transit event in the Sector 15 presearch data conditioning (PDC) light curve. We obtain spectroscopic follow-up observations of HD 332231 with the Automated Planet Finder, Keck I, and SONG telescopes. The orbital period we infer from the radial velocity (RV) observations leads to the discovery of another transit in Sector 14 that was masked by PDC due to scattered light contamination. A joint analysis of the transit and RV data confirms the planetary nature of HD 332231 b, a Saturn-size ($0.867^{+0.027}_{-0.025} \; R_{\rm J}$), sub-Saturn-mass ($0.244\pm0.021 \; M_{\rm J}$) exoplanet on a 18.71 day circular orbit. The low surface gravity of HD 332231 b and the relatively low stellar flux it receives make it a compelling target for transmission spectroscopy. Also, the stellar obliquity is likely measurable via the Rossiter-McLaughlin effect, an exciting prospect given the 0.14 au orbital separation of HD 332231 b. The spectroscopic observations do not provide substantial evidence for any additional planets in the HD 332231 system, but continued RV monitoring is needed to further characterize this system. We also predict that the frequency and duration of masked data in the PDC light curves for TESS Sectors 14-16 could hide transits of some exoplanets with orbital periods between 10.5 and 17.5 days., Comment: 17 pages, 9 figures, 4 tables. Published in the Astronomical Journal

The physical clogging of porous medium is a significant problem that impacts the performance of infiltration systems. Although the physical clogging has been extensively studied, the mesoscopic mechanism and clogging dynamic in the porous medium are still unclear. This paper focuses on the migration characteristic and physical clogging mechanism of suspended solid (SS) particles in gravel and zeolite columns. The results indicate that the permeability of the filter medium significantly decreases at the initial stage of SS infiltration and reduces to a steady value as the accumulated SS load increases. The permeability of the porous medium decreases as the particle size of the filter medium decreases, while lower particle sphericity and coarser particle texture also result in a reduction in the permeability of the porous medium. X-ray computed tomography was used to obtain images during the infiltration of the SS particles through the substrates. Due to the formation of a clogging layer, the intrusion of subsequent SS inflow can be prevented, leading to the formation of a blanket depositional layer. The ratio between the particle size of the filter medium and the SS particles controls the migration of the SS particles within the porous medium. Additionally, in this experimental study, the threshold is affected by the particle shape and texture of the filter medium. Considering the reduction in the permeability of porous medium by the clogging layer, a simple double-layered analytical model that considers SS accumulation was proposed to estimate the variation in the permeability, which agrees well with the experimental measurements.

Melanoma is a human skin malignant tumor with high invasion and poor prognosis. The limited understanding of genomic alterations in melanomas in China impedes the diagnosis and therapeutic strategy selection. We conducted comprehensive genomic profiling of melanomas from 39 primary and metastatic formalin-fixed paraffin-embedded (FFPE) samples from 27 patients in China based on an NGS panel of 223 genes. No significant difference in gene alterations was found between primary and metastasis melanomas. The status of germline mutation, CNV, and somatic mutation in our cohort was quite different from that reported in Western populations. We further delineated the mutation patterns of 4 molecular subgroups (BRAF, RAS, NF1, and Triple-WT) of melanoma in our cohort. BRAF mutations were more frequently identified in melanomas without chromic sun-induced damage (non-CSD), while RAS mutations were more likely observed in acral melanomas. NF1 and Triple-WT subgroups were unbiased between melanomas arising in non-CSD and acral skin. BRAF, RAS, and NF1 mutations were significantly associated with lymph node metastasis or presence of ulceration, implying that these cancer driver genes were independent prognostic factors. In summary, our results suggest that mutational profiles of malignant melanomas in China are significantly different from Western countries, and both gene mutation and amplification play an important role in the development and progression of melanomas.

We present the discoveries of KELT-25b (TIC 65412605, TOI-626.01) and KELT-26b (TIC 160708862, TOI-1337.01), two transiting companions orbiting relatively bright, early A-stars. The transit signals were initially detected by the KELT survey, and subsequently confirmed by \textit{TESS} photometry. KELT-25b is on a 4.40-day orbit around the V = 9.66 star CD-24 5016 ($T_{\rm eff} = 8280^{+440}_{-180}$ K, $M_{\star}$ = $2.18^{+0.12}_{-0.11}$ $M_{\odot}$), while KELT-26b is on a 3.34-day orbit around the V = 9.95 star HD 134004 ($T_{\rm eff}$ =$8640^{+500}_{-240}$ K, $M_{\star}$ = $1.93^{+0.14}_{-0.16}$ $M_{\odot}$), which is likely an Am star. We have confirmed the sub-stellar nature of both companions through detailed characterization of each system using ground-based and \textit{TESS} photometry, radial velocity measurements, Doppler Tomography, and high-resolution imaging. For KELT-25, we determine a companion radius of $R_{\rm P}$ = $1.64^{+0.039}_{-0.043}$ $R_{\rm J}$, and a 3-sigma upper limit on the companion's mass of $\sim64~M_{\rm J}$. For KELT-26b, we infer a planetary mass and radius of $M_{\rm P}$ = $1.41^{+0.43}_{-0.51}$ $M_{\rm J}$ and $R_{\rm P}$ = $1.940^{+0.060}_{-0.058}$ $R_{\rm J}$. From Doppler Tomographic observations, we find KELT-26b to reside in a highly misaligned orbit. This conclusion is weakly corroborated by a subtle asymmetry in the transit light curve from the \textit{TESS} data. KELT-25b appears to be in a well-aligned, prograde orbit, and the system is likely a member of a cluster or moving group., 24 pages, 18 figures, 8 tables

Understanding the governing processes of CO2 huff-n-puff in shales is essential for enhancing shale gas recovery and CO2 sequestration. However, existing studies have not fully accounted for the chemical composition and geometry of kerogen nanopores and the reality that natural gas is a multi-component mixture. We used grand canonical Monte Carlo (GCMC) simulations to study the competitive adsorption between CO2 and typical hydrocarbon components (CH4, C2H6, and C3H8). We further studied the recovery mechanisms of CO2 huff-n-puff within kerogenic circular nanopores at reservoir conditions. We probed the effects of pressure, pore geometry, and size on gas recovery and CO2 sequestration efficiency. Although pressure drop readily exploits CH4 in the adsorption layer, the recovery due to CO2 injection primarily occurs within the kerogen matrix for pure CH4. Injecting CO2 facilitates the recovery of heavier hydrocarbons, whereas pressure drawdown exhibits better performance for lighter components. CO2 huff-n-puff may serve as a promising method for gas exploitation in circular pores, whereas pressure drop favors the production in kerogen slit. The tremendously different gas adsorption and recovery behavior in distinct pore geometries and compositions necessitate the study using realistic shale kerogen models. Moreover, enlarging the pore size improves the recovery of each component during pressure drawdown but restrains the performance of CO2 injection; meanwhile, the total gas recovery and CO2 sequestration efficiency increase. This study provides a more in-depth understanding of multi-component gas recovery mechanisms within realistic shale kerogen nanopores and sheds light on the CO2 sequestration in shale reservoirs.

In order to control the tower deviation in the cable hoisting process of long-span concrete-filled steel tubular arch bridge during construction monitoring, a practical method of tower deviation correction was studied and established. In the paper, based on the studies about the deviation error formation mechanism of tower in the process of cable lifting, the relevant formulas of the arch rib elevation changes caused by the change of tower state were deduced. The traditional control methods including increase of tower stiffness and strength of the anchor cable, are not effective, costly, and require a longer construction period. To overcome these defects, in virtue of the Beidou GNSS measurement system and hydraulic jack active control system, the active control technology of the CFST (Concrete Filled Steel Tube) arch bridge tower deviation was thoroughly studied. Besides, a perfect active control theory was established. Finally, the author puts forward the idea of reverse pulling tower deviation. The field measurement and comparative study show that after the optimization of this method, the tower deviation is within 2 cm, and the error meets the specification requirements. The proposed method can accurately control the tower deviation in the process of arch bridge cable hoisting, and establish a set of perfect active control related systems and theories, which is especially suitable for the construction monitoring and adjustment in the construction stage of arch bridge, and can provide reference for the construction control of tower deviation of the same type of bridge.

The pyrolysis characteristics of tetrazolo[1,5-a]pyridine were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The apparent activation energy (Eα) was estimated with DSC and various kinetic analysis methods, and it was determined that the decomposition of tetrazolo[1,5-a]pyridine follows the Avarami-Erofeve (A2) reaction pattern. The thermal safety and thermodynamic parameters were calculated. In addition, the thermal runaway behavior and kinetic parameters under adiabatic conditions were studied by employing an adiabatic accelerating calorimeter (ARC). Thermogravimetric-photoionization mass spectrometry (TG-MS) was used to identify the vapor phase products of the pyrolysis process. The different decomposition pathways were analyzed by density functional theory (DFT). The main decomposition products were N2, C2H2 and HCN according to TG-MS experiments and theoretical calculations. The most likely proposed decomposition mechanism proceeded through the opening of the tetrazole ring to dissociate N2 and the rupturing of the pyridine ring to release C2H2 and HCN. The findings of these experiments and theoretical calculations can contribute to the determination of safety precautions for possible heat hazard accidents during the handling, transportation, use and storage of tetrazolo[1,5-a]pyridine.

Background: The aim of this study was to evaluate the influence of patient body mass index (BMI) and estimated creatinine clearance (CrCl) on serum vancomycin concentrations in order to define a possible optimal dosage regimen in overweight patients from data obtained during therapeutic drug monitoring.Methods: This retrospective study used data collected from January 2017 to January 2019. Adult patients (n=204) receiving vancomycin treatment at a dose of 1000 mg in every 12 h and undergoing serum monitoring. Data collected included patient gender, age, height and weight, vancomycin regimens and concentrations, and serum creatinine. In this study, statistical comparisons were made on the results from patients according to serum vancomycin concentration.Results: Serum vancomycin concentration was significantly related to BMI (P < 0.001) and CrCl (P < 0.05) in adult patients. Further, the trough serum vancomycin concentration showed a logarithmic correlation with BMI (R = -0.5108, 95 % CI: -0.6082 to -0.3982, P < 0.001) and CrCl (R = -0.5739, 95 % CI: -0.6616 to -0.4707, P < 0.001). In addition, the CrCl was significantly related to BMI (P < 0.01). Besides, some of the patients with higher BMI (≥ 24 kg/m2) met the goal trough concentration after an adjustment from 1000 mg every 12 h to 1000 mg every 8 h.Conclusions: Serum vancomycin concentration decreases progressively with increasing BMI due to the augment in CrCl in adult patients. Therefore, dose adjustment should be based on BMI and CrCl for safe and effective use of vancomycin in adult patients (BMI ≥ 24 kg/m2).

Background The aim of this study was to evaluate the influence of patient body mass index (BMI) and estimated creatinine clearance (CrCl) on serum vancomycin concentrations to define a possible optimal dosage regimen in overweight patients based on data obtained during therapeutic drug monitoring. Methods This retrospective study used data collected from January 2017 to January 2019. Adult patients (n = 204) received vancomycin treatment at a dose of 1000 mg every 12 h and underwent serum monitoring. Data collected included patient disease category, sex, age, height, weight, vancomycin concentrations, and serum creatinine. The CrCl values were estimated using the Cockcroft-Gault formula. In this study, statistical comparisons were performed on the results of patients according to serum vancomycin concentration. Results Serum vancomycin concentration was significantly related to BMI (P P R = − 0.5108, 95% CI: − 0.6082 to − 0.3982, P R = − 0.5739, 95% CI: − 0.6616 to − 0.4707, P 2) met the goal trough concentration after an adjustment from 1000 mg every 12 h to 1000 mg every 8 h. Conclusions Serum vancomycin concentration decreases progressively with increasing BMI and the augmentation in CrCl in adult patients. The trough concentration of vancomycin should be continuously monitored for patients with a BMI ≥ 24 kg/m2, and the dosage regimen should be adjusted to reach the target trough concentration in these patients to reduce the impact of BMI.

Droplet generation involving high inertial gas flow in a T-junction microchannel was experimentally and numerically studied in this work. The effect of high inertial flow on the water droplet generation was investigated based on the obtained results. At various gas Reynold (Re) numbers and liquid Capillary (Ca) numbers, the unique flow regime mapping including squeezing, dripping and jetting was observed. It was found that stable aqueous droplets are generated in the squeezing and dripping flow regimes. Visualization experiment shows that the morphology of droplets generated in the water-gas system is different from that in the traditional water-oil system. As the Re number increases or the Ca number decreases, the droplet length decreases. Increasing both Re number and Ca number can increase the detachment frequency. Based on the 3D VOF simulations, the droplet attachment to one of the channel wall during the pinch-off period and the rebound of liquid phase after droplet detachment was observed. Droplet size, detachment time and droplet generation frequency were then analyzed for the droplet generation. The dominant detachment mechanism during the whole droplet generation process was also discussed in this work.

According to the current main application mode of remote sensing satellites, users obtain the original image data, carries on the complex data processing, and get the required substantive content by filtering results after processing. The poor data timeliness, the large amount of data transmitted from satellite to ground, and the heavy workload of the ground processing system are main drawbacks of such modes. This article presents an intelligent onboard processing and multichannel transmission concept for infrared remote sensing satellites to solve above problems. Through applying cloud detection, fire spot detection, water pollution detection and other algorithms, infrared remote sensing data of the satellite payload is processed onboard, so that typical user-focused events with exact location information are discovered. The event information can be broadcast to the ground immediately through the short message channel of Chinese Beidou Navigation System, which is a real-time data transmission channel, so application users can quickly respond. In addition, there is a mid-speed data transmission channel for slicing images of areas of interest (AOI), as well as a high-speed data transmission channel for complete image data, to meet the needs of different users. In general, this article provides an overview of onboard information extraction and multichannel distribution for infrared remote sensing satellites, which can be used as a reference for satellite applications and engineering development.

In this work, we investigate the capacity of private information retrieval (PIR) from $N$ replicated databases, where a subset of the databases are untrustworthy (byzantine) in their answers to the query of the user. We allow for multi-round queries and demonstrate that the identities of the byzantine databases can be determined with a small additional download cost. As a result, the capacity of the multi-round PIR with byzantine databases (BPIR) reaches that of the robust PIR problem when the number of byzantine databases is less than the number of trustworthy databases., 8 pages, 2 figures

Background. Abnormal apoptosis of keratinocytes is one of the pathological changes of psoriasis. Caspases (CASPs) are the central engines of apoptosis. Studies to date have shown that some SNPs alter the expression of related genes and lead to changes in disease risk. However, no studies have investigated the associations between gene polymorphisms and the risk of psoriasis in Han population in northeast China. Therefore, we conducted a case-control study to explore this question in Han population of northeastern China. Methods. 540 patients with PsV and 612 healthy age- and sex-matched controls were enrolled in this study. We determined the genotypes of 17 single nucleotide polymorphisms (SNPs) from 11 genes of caspase family by the improved multiplex ligation detection reaction (iMLDR) method. A model-based single SNP frequentist test and haplotype association studies were performed to evaluate the association between SNPs and PsV. Results. In the single SNP tests, rs6704688 in CASP8 was significantly associated with psoriasis vulgaris (PsV) in Han population of northeastern China (P = 0.0169, P’ = 0.0179 under the additive model; P = 0.0126, P’ = 0.0149 under the heterozygous model). In haplotype analyses, the CASP7 haplotype GC was found to be associated with PsV risk (case group versus control group, 47.2% versus 54.4%, respectively, p = 0.0149). Conclusions. Our study presented that the gene polymorphisms of CASP7 and CASP8 were significantly associated with PsV in Han population of northeastern China, which implied the functional relationship between PsV and caspase genes. CASP8 and CASP7 SNPs could be new potential biomarkers for risk stratification and prevention of PsV.

We present the discovery of KELT-22Ab, a hot Jupiter from the KELT-South survey. KELT-22Ab transits the moderately bright (V∼11.1) Sun-like G2V star TYC 7518-468-1. The planet has an orbital period of P = 1.3866529±0.0000027 days, a radius of R_P = 1.285^(+0.12)_(−0.071) R_J, and a relatively large mass of M_P = 3.47^(+0.15)_(−0.14) M_J. The star has R⋆ = 1.099^(+0.079)_(−0.046) R⊙, M⋆ = 1.092^(+0.045)_(−0.041) M⊙, T_(eff) = 5767^(+50)_(−49) K, log g⋆ = 4.393^(+0.039)_(−0.060) (cgs), and [m/H] = +0.259^(+0.085)_(−0.083), and thus, other than its slightly super-solar metallicity, appears to be a near solar twin. Surprisingly, KELT-22A exhibits kinematics and a Galactic orbit that are somewhat atypical for thin disk stars. Nevertheless, the star is rotating quite rapidly for its estimated age, shows evidence of chromospheric activity, and is somewhat metal rich. Imaging reveals a slightly fainter companion to KELT-22A that is likely bound, with a projected separation of 6” (∼1400 AU). In addition to the orbital motion caused by the transiting planet, we detect a possible linear trend in the radial velocity of KELT-22A suggesting the presence of another relatively nearby body that is perhaps non-stellar. KELT-22Ab is highly irradiated (as a consequence of the small semi-major axis of a/R⋆ = 4.97), and is mildly inflated. At such small separations, tidal forces become significant. The configuration of this system is optimal for measuring the rate of tidal dissipation within the host star. Our models predict that, due to tidal forces, the semi-major axis of KELT-22Ab is decreasing rapidly, and is thus predicted to spiral into the star within the next Gyr.

The future of exoplanet science is bright, as TESS once again demonstrates with the discovery of its longest-period confirmed planet to date. We hereby present HD 21749b (TOI 186.01), a sub-Neptune in a 36-day orbit around a bright (V = 8.1) nearby (16 pc) K4.5 dwarf. TESS measures HD21749b to be 2.61$^{+0.17}_{-0.16}$ $R_{\oplus}$, and combined archival and follow-up precision radial velocity data put the mass of the planet at $22.7^{+2.2}_{-1.9}$ $M_{\oplus}$. HD 21749b contributes to the TESS Level 1 Science Requirement of providing 50 transiting planets smaller than 4 $R_{\oplus}$ with measured masses. Furthermore, we report the discovery of HD 21749c (TOI 186.02), the first Earth-sized ($R_p = 0.892^{+0.064}_{-0.058} R_{\oplus}$) planet from TESS. The HD21749 system is a prime target for comparative studies of planetary composition and architecture in multi-planet systems., Comment: Published in ApJ Letters; 5 figures, 1 table

NASA's Transiting Exoplanet Survey Satellite (TESS) mission is expected to discover hundreds of planets via single transits first identified in their light curves. Determining the orbital period of these single transit candidates typically requires a significant amount of follow-up work to observe a second transit or measure a radial velocity orbit. In Yao et al. (2019), we developed simulations that demonstrated the ability to use archival photometric data in combination with TESS to "precover" the orbital period for these candidates with a precision of several minutes, assuming circular orbits. In this work, we incorporate updated models for TESS single transits, allowing for eccentric orbits, along with an updated methodology to improve the reliability of the results. Additionally, we explore how radial velocity (RV) observations can be used to follow up single transit events, using strategies distinct from those employed when the orbital period is known. We find that the use of an estimated period based on a circular orbit to schedule reconnaissance RV observations can efficiently distinguish eclipsing binaries from planets. For candidates that pass reconnaissance RV observations, we simulate RV monitoring campaigns that enable one to obtain an approximate orbital solution. We find this method can regularly determine the orbital periods for planets more massive than 0.5 M_J with orbital periods as long as 100 days., 28 pages, 11 figures, accepted for publication in the Astronomical Journal

Gas storage in shale primarily includes three forms: free gas in the fractures or macropores, adsorbed gas upon the kerogen surface, and absorbed gas in the kerogen matrix. However, current techniques cannot distinguish the adsorbed and absorbed gas, which restrict the understanding of gas storage and transport mechanisms through shale kerogen. On the basis of the grand canonical Monte Carlo (GCMC) simulations, we propose a technique to determine the independent adsorption and absorption isotherms of methane within slit-shaped shale kerogen under supercritical conditions. We observe that if the pore pressure is higher than ~3.5 MPa, the absorption amount is much smaller than that of adsorbed gas; however, at lower pressures, the absorption capacity is superior to that of the adsorption. Meanwhile, the ratio between adsorption and absorption quantities continuously increases with pressure. We probe the underlying mechanisms and study the effect of slit aperture, temperature, as well as moisture on gas adsorption and absorption capacity. Enlarging the slit aperture increases the adsorbed gas contents but shows only a negligible effect on the absorption capacity. Heating facilitates the escapement of gas molecules, thus leading to the inhibition of both adsorption and absorption capacities. Water molecules occupying the adsorption site on the slit surface impedes methane adsorption, but the absorption capacity within the kerogen matrix remains unchanged. This work elucidates the gas adsorption and absorption behavior in shale kerogen and sheds light on the storage and transport of hydrocarbons in nanoporous materials.

5-(4-Pyridyl)tetrazolate-methylene tetrazole (H4-PTZ-methylene tetrazole) was prepared. Thermokinetic characteristics of H4-PTZ-methylene tetrazole were described through differential scanning calorimetry (DSC). Ozawa method, Kissinger method, and isoconversional approach were used to calculate the kinetic parameters. Thermal safety parameters, such as self-accelerated decomposition temperature (SADT) and thermal ignition temperature (TTIT), were evaluated from experimental results. The initial decomposition process was investigated using experimental and theoretical calculations. Geometric optimisation, Mulliken charges, electrostatic potentials, and decomposition pathways were explored using Gaussian 16. The simultaneous dissociation of C7–N8 and N9–N10 bonds (DM1) and of C13–N17 and N15–N16 bonds (DM2) had lower energy barriers. The theoretical apparent activation energy was higher than the experimental one. As a novel finding, the exothermic process observed through DSC was primarily because of the reaction that opened the tetrazole ring, which released nitrogen.

Daily electricity consumption in summer is affected by numerous meteorological factors. In order to improve the accuracy of daily electricity consumption forecasting, a summer daily electricity consumption combination forecasting model based on daily characteristic meteorological factors is proposed in this paper. Firstly, the relationship between various meteorological indexes and daily electricity consumption is analysed considering the coupling effect and accumulative effect of meteorological factors on daily electricity consumption, and a single forecast model of daily electricity consumption is established. Then the meteorological mapping function is designed to evaluate the impact of each meteorological index on daily electricity consumption, and the weight of each single forecasting model is calculated. Finally, a combination forecasting model of daily electricity consumption in summer is established. The parameters of meteorological mapping function are optimized by adaptive training and virtual forecasting, and solved by genetic algorithm. Taking the daily electricity consumption in Chongqing in the summer of 2018 as an example, the results have shown that the proposed combination forecasting model can effectively improve the accuracy of daily electricity consumption forecasting.

Recently, more and more researchers have devoted their efforts to developing flexible electrochemical energy storage devices to meet the development of portable and wearable electronics. Among them, supercapacitors (SCs) have been widely studied due to their high specific capacitance and power density. However, most flexible SCs often use traditional carbon materials and transition metal oxides as electrode materials. In this paper, we used an easy and low-cost way to fabricate a flexible supercapacitor based on a new type of two-dimensional material, transition metal carbides, nitrides, or carbonitrides (MXenes). By taking full advantage of the hydrophilicity and metal conductivity of MXene nanosheets, an extremely simple “dipping and drying” method was used to achieve conductive textile electrodes with a specific capacitance of 182.70 F g−1, which is higher than reported for carbon nanotubes (CNTs) and active carbon. To further improve the capacitive performance of the MXene-based electrode and avoid the poor oxygen oxidation of MXene, polypyrrole (PPy) was electrochemically deposited on the surface of MXene textiles, thus producing a PPy–MXene coated textile electrode with a specific capacitance of 343.20 F g−1. In addition, a symmetrical solid-state supercapacitor based on MXene–PPy textiles was assembled, which achieved an energy density of 1.30 mW h g−1 (power density = 41.1 mW g−1). This work introduces a new type of MXene-based textile SC, which provides a promising candidate for flexible and wearable energy storage devices.

In 2015, K2 observations of the bright (V = 8.9, K = 7.7) star HIP 41378 revealed a rich system of at least five transiting exoplanets, ranging in size from super-Earths to gas giants. The 2015 K2 observations only spanned 74.8 days, and the outer three long-period planets in the system were only detected with a single transit, so their orbital periods and transit ephemerides could not be determined at that time. Here, we report on 50.8 days of new K2 observations of HIP 41378 from summer 2018. These data reveal additional transits of the long-period planets HIP 41378 d and HIP 41378 f, yielding a set of discrete possible orbital periods for these two planets. We identify the most probable orbital periods for these two planets using our knowledge of the planets' transit durations, the host star's properties, the system's dynamics, and data from the ground-based HATNet, KELT, and WASP transit surveys. Targeted photometric follow-up during the most probable future transit times will be able to determine the planets' orbital periods, and will enable future observations with facilities like the James Webb Space Telescope. The methods developed herein to determine the most probable orbital periods will be important for long-period planets detected by the Transiting Exoplanet Survey Satellite, where similar period ambiguities will frequently arise due to the telescope's survey strategy., Comment: accepted to AJ in Nov 2018

The Kilodegree Extremely Little Telescope (KELT) project has been conducting a photometric survey for transiting planets orbiting bright stars for over ten years. The KELT images have a pixel scale of ~23"/pixel---very similar to that of NASA's Transiting Exoplanet Survey Satellite (TESS)---as well as a large point spread function, and the KELT reduction pipeline uses a weighted photometric aperture with radius 3'. At this angular scale, multiple stars are typically blended in the photometric apertures. In order to identify false positives and confirm transiting exoplanets, we have assembled a follow-up network (KELT-FUN) to conduct imaging with higher spatial resolution, cadence, and photometric precision than the KELT telescopes, as well as spectroscopic observations of the candidate host stars. The KELT-FUN team has followed-up over 1,600 planet candidates since 2011, resulting in more than 20 planet discoveries. Excluding ~450 false alarms of non-astrophysical origin (i.e., instrumental noise or systematics), we present an all-sky catalog of the 1,128 bright stars (6, Comment: Accepted for publication in AJ, 21 pages, 12 figures, 7 tables

We present the discovery of KELT-21b, a hot Jupiter transiting the $V=10.5$ A8V star HD 332124. The planet has an orbital period of $P=3.6127647\pm0.0000033$ days and a radius of $1.586_{-0.040}^{+0.039}$ $R_J$. We set an upper limit on the planetary mass of $M_P, Comment: Accepted for publication in AJ. Updated to match accepted version. 25 pages, 14 figures

We present the discovery of the giant planet KELT-19Ab, which transits the moderately bright $(\mathrm{V} \sim 9.9)$ A8V star TYC 764-1494-1 with an orbital period of 4.61 days. We confirm the planetary nature of the companion via a combination of radial velocities, which limit the mass to $< 4.1\,\mathrm{M_J}$ $(3\sigma)$, and a clear Doppler tomography signal, which indicates a retrograde projected spin-orbit misalignment of $\lambda = -179.7^{+3.7}_{-3.8}$ degrees. Global modeling indicates that the $\rm{T_{eff}} =7500 \pm 110\,\mathrm{K}$ host star has $\mathrm{M_*} = 1.62^{+0.25}_{-0.20}\,\mathrm{M_\odot}$ and $\mathrm{R_*} = 1.83 \pm 0.10\,\mathrm{R_\odot}$. The planet has a radius of $\mathrm{R_P}=1.91 \pm 0.11\,\mathrm{R_J}$ and receives a stellar insolation flux of $\sim 3.2\times 10^{9}\,\mathrm{erg\,s^{-1}\,cm^{-2}}$, leading to an inferred equilibrium temperature of $\rm{T_{EQ}} = \sim 1935\,\rm{K}$ assuming zero albedo and complete heat redistribution. With a $v\sin{I_*}=84.8\pm 2.0\,\mathrm{km\,s^{-1}}$, the host is relatively slowly rotating compared to other stars with similar effective temperatures, and it appears to be enhanced in metallic elements but deficient in calcium, suggesting that it is likely an Am star. KELT-19A would be the first detection of an Am host of a transiting planet of which we are aware. Adaptive optics observations of the system reveal the existence of a companion with late G9V/early K1V spectral type at a projected separation of $\approx 160\,\mathrm{AU}$. Radial velocity measurements indicate that this companion is bound. Most Am stars are known to have stellar companions, which are often invoked to explain the relatively slow rotation of the primary. In this case, the stellar companion is unlikely to have caused the tidal braking of the primary. However, it may have emplaced the transiting planetary companion via the Kozai-Lidov mechanism., Comment: Published in The Astronomical Journal. 18 pages, 14 figures, 6 tables

This paper addresses the problem of task allocation in real-time distributed systems with the goal of maximizing the system reliability, which has been shown to be NP-hard. We take account of the deadline constraint to formulate this problem and then propose an algorithm called chaotic adaptive simulated annealing (XASA) to solve the problem. Firstly, XASA begins with chaotic optimization which takes a chaotic walk in the solution space and generates several local minima; secondly XASA improves SA algorithm via several adaptive schemes and continues to search the optimal based on the results of chaotic optimization. The effectiveness of XASA is evaluated by comparing with traditional SA algorithm and improved SA algorithm. The results show that XASA can achieve a satisfactory performance of speedup without loss of solution quality.

We announce the discovery of KELT-23Ab, a hot Jupiter transiting the relatively bright ($V=10.3$) star BD+66 911 (TYC 4187-996-1), and characterize the system using follow-up photometry and spectroscopy. A global fit to the system yields host-star properties of $T_{eff}=5900\pm49 K$, $M_*=0.945^{+0.060}_{-0.054} M_{\odot}$, $R_*=0.995\pm0.015 R_{\odot}$, $L_*=1.082^{+0.051}_{-0.048} L_{\odot}$, log$g_{*}=4.418^{+0.026}_{-0.025}$ (cgs), and $\left[{\rm Fe}/{\rm H}\right]=-0.105\pm0.077$. KELT-23Ab is a hot Jupiter with mass $M_P=0.938^{+0.045}_{-0.042} M_{\rm J}$, radius $R_P=1.322\pm0.025 R_{\rm J}$, and density $\rho_P=0.504^{+0.038}_{-0.035}$ g cm$^{-3}$. Intense insolation flux from the star has likely caused KELT-23Ab to become inflated. The time of inferior conjunction is $T_0=2458149.40776\pm0.00091~\rm {BJD_{TDB}}$ and the orbital period is $P=2.255353^{+0.000031}_{-0.000030}$ days. There is strong evidence that KELT-23A is a member of a long-period binary star system with a less luminous companion, and due to tidal interactions, the planet is likely to spiral into its host within roughly a Gyr. This system has one of the highest positive ecliptic latitudes of all transiting planet hosts known to date, placing it near the Transiting Planet Survey Satellite and James Webb Space Telescope continuous viewing zones. Thus we expect it to be an excellent candidate for long-term monitoring and follow-up with these facilities., Comment: 17 pages, 10 figures, Accepted for publication in AJ

In multi-agent system like the pursuit-evasion games(PEGs), when the pursuer tries to capture the evader by encircling it, there should be a method to determine whether the encirclement is situated and therefor form a feedback mechanism to direct latter tactics of pursuers. At present, problems of this kind are solved by the pursuer's “limbs contact” or “attack range ”, but these methods doesn't take the dynamic characteristic of participants in consideration, which lead no guidance of moving tactics. This passage propose a method based on geometric analysis, consider the velocity of both pursuer and evader, and obtain a method to determine surrounding situation. Present the necessary condition of the formation of encirclement situation, which can be successfully applied in pursuit-evasion games. Furthermore, a task allocation algorithm based on least tactical target point is proposed, which is also of great feasibility.

Multidrug resistance (MDR) remains the major obstacle to the success of clinical cancer chemotherapy. P-glycoprotein (P-gp), encoded by the MDR1, is an important part with complex mechanisms associated with the MDR. In order to overcome the MDR of tumors, we in the present experimental design incorporated small interfering RNA (siRNA) targeting MDR1 gene and anticancer drug paclitaxel (PTX) into the solid lipid nanoparticles (SLNs) to achieve the combinational therapeutic effects of genetherapy and chemotherapy. In this study, siRNA-PTX-SLNs were successfully prepared. The cytotoxicity of blank SLNs and siRNA-PTX-SLNs in MCF-7 cells and MCF-7/ADR cells were detected by MTT; and the uptake efficiency of PTX in MCF-7/ADR cells were detected via HPLC method; quantitative real-time PCR and flow cytometry were performed to investigate the silencing effect of siRNA-PTX- SLNs on MDR1 gene in MCF-7/ADR cells. The results showed that PTX loaded SLNs could significantly inhibit the growth of tumor cells, and more importantly, the MDR tumor cells treated with siRNA-PTX-SLNs showed the lowest viability. HPLC study showed that SLNs could enhance the cellular uptake for PTX. Meanwhile, siRNA delivered by SLNs significantly decreased the P-gp expression in MDR tumor cells, thus increased the cellular accumulation of rhodamine123 as a P-gp substrate. In conclusion, the MDR1 gene could be silenced by siRNA-PTX-SLNs, which could promote the growth inhibition efficiency of PTX on tumor cells, leading to synergetic effect on MDR tumor therapy.

Ag–graphene/epoxy nanocomposites were prepared by an in situ method using Ag–graphene nanocomposites as additives. The electrical properties of the Ag–graphene/epoxy nanocomposites were investigated by current–voltage ( I – V ) tests. The result showed that the nanocomposites with filler contents between 0.8 and 3.0 wt.% exhibited a varistor effect. This reversible electrical nonlinearity resulted from the defects in the GO-derived graphene structure and the presence of the Ag nanoparticles.

Background: Medical film digitizers play an important transitory role as digital–analogue bridges in radiology. Digitized mammograms require evaluation of performance to assure medical image quality. Purpose: To compare the diagnostic accuracy in the interpretation of breast masses using original screen-film mammograms versus digitized images. Material and Methods: A total of 72 female patients between 55 and 81 years of age suspected of having breast cancer were selected by two non-observing radiologists. Of these, 31 cases were benign lesions and 41 cases were cancer. The mammography films were digitized using a laser film digitizer. Three radiologists, each with more than 10 years of experience in mammography, interpreted the screen-film mammograms and digitized images respectively. The time interval was 4 weeks. A four-point malignancy scale was used, with 1 defined as definitely not malignant, 2 as probably not malignant, 3 as probably malignant, and 4 as definitely malignant. Receiver operating characteristic (ROC) curves, sensitivity, and specificity were compared. Results: The average area-under-the-curve (Az) value of the original screen-film mammograms was 0.921, and the average Az value of the digitized images was 0.859. This difference was not statistically significant ( P=0.131). The detection specificity of extremely dense breasts was lower than that for other breast compositions for both digitized images and screen-film mammograms. No statistical significance in sensitivity and specificity was observed between digitized images and mammograms for each breast composition. Original screen-film mammograms were observed to perform better than digitized images. Conclusion: Digitized images with a spatial resolution of 175 µm can be used instead of screen-film mammograms in the diagnosis of breast cancer.

UAV detection task planning has been significantly applied in many domains. As a famous optimizing algorithm, the ant colony algorithm (ACA) has a good performance to solve problem of this kind because of its positive feedback characteristic. The problem of the standard ACA is that only one starting point is considered when ACA is used in UAV detection task planning. In allusion to the UAV detection task planning problem of multiple starting points, a multi-start ant colony algorithm (MS-ACA) is proposed, deferent ant colonies are allocated to every UAV starting point. To lead the searching direction, the target is marked by a shared tabu table and a shared decision table. The results of experiment prove that the MS-ACA is able to find an optimized deploying and scheduling policy of UAVs, which conforms to the scenario requirement, and is with preferable adaptation.

With the widely use of CAN in the industrial control field, means of transportation, and so on, it is significant to improve the performance of the corresponding simulation platform to make them be more useful for simulating the systems using CAN cards. Firstly, this paper introduces the overall structure of the KD-DRT simulation platform and the characteristic of CAN. Second, determines the form of the CAN card model according to demand. Then designs the CAN card model in 3 respects: the inner structure of a CAN node, variables and API functions. Finally, analyses the main workflow of the model.

KD-DRT simulation platform tries to manage MATLAB/Simulink models, and make them compatible and cooperating with other C/C++ models in distributed real- time simulation. MATLAB/Simulink together with KD-DRT are compared and analyzed in system structure and properties. The shortages of MATLAB/Simulink in distributed real-time simulation are proposed, and KD-DRT is chosen as the support platform instead. KD-DRT chooses S-Function mode to create simulation models, and chooses Target Language Compiler(TLC) to inline S-Function and collect information of relationship, parameters and ports from Simulink models. Correlated RTW file is created and the structure is analyzed to extract these informations through TLC. Tests are carried out in the end to prove that KD-DRT can control parameters of Simulink models online, and transfer signals between multiple models outside the MATLAB environment. KD-DRT proves to be more suitable to serve as the support platform for distributed real-time simulation ,and is able to combine Simulink models with C/C++ ones in simulation system.

To improve the real-time property for typical Pulse Doppler radar simulation, an idea of signal-level simulation using hardware was proposed. The system framework and information flow was studied, then a host method of moving target echo simulation was given. Most of all, radar signal processing was realized by FPGA, which includes digital quadrature detection with IF sampling, pulse compression based on LFM, moving target detection with FFT filter, and cell average CFAR function modules. Finally, the target distance and velocity was achieved. The technology discussed could be used for single-radar precise simulation and electronic warfare simulation of multi-radars.

According to the different time constraints for simulation tasks, a multi-level distributed real-time simulation platform was proposed, on which hardware layer was mainly introduced to solve rigorous real-time tasks. The distributed simulation framework under centralized management was given. Then, FPGA and DSP hardware boards were well designed. Especially, reflective memory network and bottom hardware communication were studied. An external clock synchronization module in FPGA was given to achieve microsecond precision. Also, data dispatch and simulation scheduling mechanism were elaborated. Finally, a real-time PD radar simulation system is developped as a typical application.

In recent years, it has become a focus to make use of the address recognition technology to improve the performance of mail sorting machines. The research in the postal address recognition, which extends the context relation from words to sentences with the use of the address information in post-processing, can effectively improve the recognition performance. In this paper, we propose a divide-and-rule method. The address is divided into high level address and low level address. For high level address, the similarity method with HLA database is presented. For low level address, the Syllable-based language model which applies to Pinyin is discussed. Then a new similarity method in multi-mode is introduced. After post-processing, for high level address, the hit rate rises from 87.63% to 95.12% while the accuracy rate declines by 2.67%, and for low level address, the hit rate increases from 58.16% to 91.81% while the accuracy rate decreases by 9.40%.

Pulse-Compression radar signal processing simulation platform provides a new way on radar digital signal processing, which is not only low-cost, easy maintenance, as well as the characters of standardization, modularization, scalability and restructure. In this paper, we present a Pulse-Compression radar echo signal processing simulation framework and module structure based on pulse compression approach, and analyze the system's data stream through a set of simulation data in interaction, encapsulation and generalization.

Time synchronization is one of the key points in distributed real-time computer system. At first, a time synchronization method under 1PPS signal is put forth. Secondly, two kinds of relevant synthetic disturbance are analyzed, and time synchronization logic is studied to cope with the disturbance. Arena software is chosen to model and simulate the time synchronization procedure. At last, the whole simulation model is constructed and the experiment results are given out to prove the efficiency of the synchronization method.

Background: The JPEG 2000 compression technique has recently been introduced into the medical imaging field. It is critical to understand the effects of this technique on the detection of breast masses on digitized images by human observers. Purpose: To evaluate whether lossless and lossy techniques affect the diagnostic results of malignant and benign breast masses on digitized mammograms. Material and Methods: A total of 90 screen-film mammograms including craniocaudal and lateral views obtained from 45 patients were selected by two non-observing radiologists. Of these, 22 cases were benign lesions and 23 cases were malignant. The mammographic films were digitized by a laser film digitizer, and compressed to three levels (lossless and lossy 20:1 and 40:1) using the JPEG 2000 wavelet-based image compression algorithm. Four radiologists with 10–12 years’ experience in mammography interpreted the original and compressed images. The time interval was 3 weeks for each reading session. A five-point malignancy scale was used, with a score of 1 corresponding to definitely not a malignant mass, a score of 2 referring to not a malignant mass, a score of 3 meaning possibly a malignant mass, a score of 4 being probably a malignant mass, and a score of 5 interpreted as definitely a malignant mass. The radiologists’ performance was evaluated using receiver operating characteristic analysis. Results: The average Az values for all radiologists decreased from 0.8933 for the original uncompressed images to 0.8299 for the images compressed at 40:1. This difference was not statistically significant. The detection accuracy of the original images was better than that of the compressed images, and the Az values decreased with increasing compression ratio. Conclusion: Digitized mammograms compressed at 40:1 could be used to substitute original images in the diagnosis of breast cancer.

In this paper, we report the detections of stellar variabilities from the first two years of observations of a sky area of about 1300 square degrees from the Tsinghua University-NAOC Transient Survey. A total of 1237 variable stars (including 299 new ones) were detected with a brightness

Simulation is an important technology in a spacecraft's whole lifecycle. To better facilitate spacecraft modeling and simulation development as well as model integration and reuse, a flexible cooperative modeling and simulation framework which is based on data driven methodology and DEVS (discrete event system specification) is proposed. To verify its effectiveness, a concrete realization of this kind of system was developed and its use in our digital spacecraft design platform indicates that it has good simulation adaptabilities and is suited to improve model composabilities.