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This article considers the problem of modeling a class of nonstationary count time series using multiple change-points generalized integer-valued autoregressive (MCP-GINAR) processes. The minimum description length principle (MDL) is applied to study the statistical inference for the MCP-GINAR model, and the consistency results of the MDL model selection procedure are established respectively under the condition of known and unknown number of change-points. To find the ``best" combination of the number of change-points, the locations of change-points, the order of each segment and its parameters, a genetic algorithm with simulated annealing is implemented to solve this difficult optimization problem. In particular, the simulated annealing process makes up for the precocious problem of the traditional genetic algorithm. Numerical results from simulation experiments and three examples of real data analyses show that the procedure has excellent empirical properties., Comment: 32 pages, 6 figures

The mobility of Leidenfrost drop has been exploited for the manipulation of drop motions. In the classical model, the Leidenfrost drop was levitated by a vapor cushion, in the absence of touch to the surface. Here we report a standing Leidenfrost state on a heated hydrophobic surface where drop stands on the surface with partial adhesion and further self-rotates like Sufi-whirling. To elucidate this new phenomenon, we imaged the evolution of the partial adhesion, the inner circulation, and the ellipsoidal rotation of the drop. The stable partial adhesion is accompanied by thermal and mechanical equilibrium, and further drives the development of the drop rotation., Comment: 16 pages, 4 figures

sj-pdf-1-ear-10.1177_0145561320947632 for Comparison of Bioabsorbable Steroid-Eluting Sinus Stents Versus Nasopore After Endoscopic Sinus Surgery: A Multicenter, Randomized, Controlled, Single-Blinded Clinical Trial by Zhenxiao Huang, Bing Zhou, Dehui Wang, Hongrui Zang, Huankang Zhang, Huan Wang, Shenqing Wang, Lei Cheng, Jinrang Li, Wenying Wu, Huifang Zhou and Huili Wu in Ear, Nose & Throat Journal

In current field application of the smart substation, the normal flow is affected by the extensive flow control method of the process layer network. In this paper, the characteristics of process-layer network traffic and the importance of flow control are analyzed. An accurate process layer network flow control strategy is proposed based on virtual link. Virtual link information is extracted based on the SCD file, and the theoretical flow information is derived for each port of the process layer switch. As a result, the virtual link flow control strategy can be designed for each port. The proposed accurate flow control method is implemented via the switch access list control by configuration. Experiments are designed to confirm that this method is simple and feasible.

Supplementary_Table_1_R2 for Comparison of Bioabsorbable Steroid-Eluting Sinus Stents Versus Nasopore After Endoscopic Sinus Surgery: A Multicenter, Randomized, Controlled, Single-Blinded Clinical Trial by Zhenxiao Huang, Bing Zhou, Dehui Wang, Hongrui Zang, Huankang Zhang, Huan Wang, Shenqing Wang, Lei Cheng, Jinrang Li, Wenying Wu, Huifang Zhou and Huili Wu in Ear, Nose & Throat Journal

The smart substation communication network is the basis for information sharing of various devices in the substation. Its operation status has an important impact on the safe operation of the substation and even the power grid. Therefore, real-time status monitoring of the smart substation communication network is becoming more and more important. Aiming at the problems of single dimension, insufficient real-time performance and manual fault analysis in existing substation communication network state monitoring technology, this paper proposes a method of smart substation communication network state monitoring and fault prediction based on network communication quality. This paper uses switch ACL technology and coloring technology to obtain communication quality indexes such as bandwidth utilization, delay, and packet loss rate in real time; based on a multi-dimensional evaluation algorithm, a comprehensive evaluation model of network communication quality is constructed; the model of the relationship between abnormal network communication quality and failures is established. Finally, real-time monitoring of network communication quality and fault prediction are realized. The application analysis in a typical 110 kV substation shows that this method can effectively evaluate the network communication quality and accurately predict failures, and can guide operationer and maintenaner to quickly restore the normal operation of the communication network.

Directed, long-range and self-propelled transport of droplets on solid surfaces, especially on water repellent surfaces, is crucial for many applications from water harvesting to bio-analytical devices. One appealing strategy to achieve the preferential transport is to passively control the surface wetting gradients, topological or chemical, to break the asymmetric contact line and overcome the resistance force. Despite extensive progress, the directional droplet transport is limited to small transport velocity and short transport distance due to the fundamental trade-off: rapid transport of droplet demands a large wetting gradient, whereas long-range transport necessitates a relatively small wetting gradient. Here, we report a radically new strategy that resolves the bottleneck through the creation of an unexplored gradient in surface charge density (SCD). By leveraging on a facile droplet printing on superamphiphobic surfaces as well as the fundamental understanding of the mechanisms underpinning the creation of the preferential SCD, we demonstrate the self-propulsion of droplets with a record-high velocity over an ultra-long distance without the need for additional energy input. Such a Leidenfrost-like droplet transport, manifested at ambient condition, is also genetic, which can occur on a variety of substrates such as flexible and vertically placed surfaces. Moreover, distinct from conventional physical and chemical gradients, the new dimension of gradient in SCD can be programmed in a rewritable fashion. We envision that our work enriches and extends our capability in the manipulation of droplet transport and would find numerous potential applications otherwise impossible., Comment: 11 pages, 4 figures

In this work, a novel ultrasonic-assisted thermal cracking method for improving the yield of light oil from the thermal cracking of Huizhou atmospheric residue (HAR) is proposed and demonstrated. To achieve this, a self-developed autoclave ultrasonic reactor (20 kHz; 200 W) was designed. Gas chromatography (GC), and elemental analyser (EA) were employed to analyse the composition of gaseous and liquid products after the cracking of residual oil. Compared to the traditional thermal cracking process under similar conditions (430 °C; 8 MPa; 2 h), the ultrasonic-based process produced lower gas products (ca. 0.6%), higher gasoline and diesel fractions (ca. 10%), vacuum residue, and lower yield of coke yield (ca. 4%). In addition, coke produced by the ultrasonic-assisted thermal cracking method exhibited spherical morphology with narrow size distribution and smooth surface with small amounts of adsorbents attached to it. The derivative characteristic peak (101 crystal face) at 2θ of 43.56° belonged to α-graphite. The abnormal high local temperature and pressure conditions produced by ultrasonication were the key factors for the thermal cracking of residual oil. The experimental results indicated that the ultrasonic-assisted thermal cracking can dramatically lead to higher yield of light oil, higher degree of cleavage, and more favourable reactions under the same conditions (as those of traditional thermal cracking). Therefore, compared to the traditional delayed coking process, the proposed ultrasonic-assisted technology can significantly decrease the power consumption. This study has vital significance in predicting and enhancing the performance of thermal cracking on a large scale.

In this text, we establish the risk model based on AR(1) series and propose the basic model which has a dependent structure under intensity of claim number. Considering some properties of the risk model, we take advantage of newton iteration method to figure out the adjustment coefficient and estimate the exponential upper bound of ruin probability. This is significant to refine the research of ruin theory. As a result, our theory will help develop insurance industry stably., Comment: 9 pages

The accurate geometry and effective control during the ring rolling process are the prerequisites for the ring products’ precise forming. In this paper, the interaction modes and rules between ring and rolls in vertical hot ring rolling (VHRR) process are analyzed, and the change laws of the ring’s geometry are studied. Based on the ABAQUS/Explicit software and its subroutine VUAMP, the finite element (FE) model of the VHRR process with measurement and control is established. Then, the ring rolling process of a groove-section profile ring is simulated. During the simulation, the ring’s outer diameter, roundness error, and the stability of the rolling process are detected in time, and the close-loop control of feed plan of the drive roll and measuring roll are also employed. The results obtained show the following: (1) Four feed stages are divided by means of a step-down feed movement, that is, bite stage, main rolling stage, precise forming stage, and sizing stage. (2) At bite and main rolling stages of the VHRR process, the ring’s center swings in a spiral line, and the rolling process is unstable, the ring’s roundness becomes worse, while the process is entering the precise forming stage, by means of the guide roll, the rolling process becomes steady and the ring’s roundness tends to be better. (3) The measuring roll contacts with the ring at the main rolling stage, afterwards, it is pushed back at the precise forming stage by ring’s growth. When the measuring roll meets the desired displacement value, a stop feeding command will be fed back, and the ring rolling process enters the sizing stage. At the sizing stage, the ring’s outer diameter still increases a little. (4) A series of VHRR experiments are conducted, and FE results are in good agreement with experimental results. The absolute errors of the ring’s outer diameter and the roundness are within 1 mm. The research results of this paper have practical significance to guide the VHRR production.

To enhance the gas–liquid mixing efficiency of the quench box in a hydroprocessing reactor, a novel structure based on supergravitational swirling flow was proposed. To reach supergravitational flow, the Froude number of liquid in the horizontal swirling tube should be greater than unity. Through computational fluid dynamics (CFD) simulation and using a high-speed camera, the supergravitational swirling flow was visualized. Based on the Higbie’s penetration theory, CFD simulation was conducted to estimate the gas–liquid mass-transfer coefficient, and was compared with the oxygen absorption experiment. It shows the gas flow rate plays a key role in the gas–liquid mixing performance in the quench box. Experiments were also carried out to investigate effects of operating condition on the pressure drop of the two-phase flow in quench box, and a correlation was proposed accordingly.