Cost-Effectiveness of Public Health Measures to Control COVID-19 in China: A Microsimulation Modeling Study

This study aimed to assess the cost-effectiveness of various public health measures in dealing with coronavirus disease 2019 (COVID-19) in China. A stochastic agent-based model was used to simulate the progress of the COVID-19 outbreak in scenario I (imported one case) and scenario II (imported four cases) with a series of public health measures. The main outcomes included the avoided infections and incremental cost-effectiveness ratios (ICERs). Sensitivity analyses were performed to assess uncertainty. The results indicated that isolation-and-quarantine averted the COVID-19 outbreak at the lowest ICERs. The joint strategy of personal protection and isolation-and-quarantine averted one more case than only isolation-and-quarantine with additional costs. The effectiveness of isolation-and-quarantine decreased with lowering quarantine probability and increasing delay time. The strategy that included community containment would be cost-effective when the number of imported cases was >65, or the delay time of the quarantine was more than 5 days, or the quarantine probability was below 25%, based on current assumptions. In conclusion, isolation-and-quarantine was the most cost-effective intervention. However, personal protection combined with isolation-and-quarantine was the optimal strategy for averting more cases. The community containment could be more cost-effective as the efficiency of isolation-and-quarantine drops and the imported cases increases.

Ламинарный хаос в связанных системах с запаздыванием

The possibility of the existence of laminar chaos in coupled time-delayed feedback systems is investigated. The cases of unidirectional and mutual coupling of time-delay systems are considered. It is shown for the first time that laminar chaos can exist not only in a system with a variable delay time, but also in a system with a constant delay time, if it is coupled with a system in the regime of laminar chaos.

Computer Technology-Based Three-Dimensional Animation Production System Management

Animation is one of the most fascinating industries in recent years. Nowadays, the most popular three-dimensional animation creation design, three-dimensional animation creation is to rely on CG technology to simulate and realize through the powerful computing power of computers. As designers have higher and higher requirements for animation, the animation creation process has become more complicated, so the skill-based management of the 3D animation creation process will be a problem. This article will study the management of the 3D animation creation system based on computer technology. On the basis of the literature, the relevant theory of the 3D animation creation system is understood, and then the computer technology-based 3D animation creation management system is designed, and the designed system is tested. The test results show that the maximum concurrency of the system in this article The number is 400. After 400, the delay time and packet loss of the system start to rise.

Effects of Pressure and Coal Rank on the Oxy-Fuel Combustion of Pulverized Coal

Pressurized oxy-fuel combustion technology is the second generation of oxy-fuel combustion technology and has low energy consumption and low cost. In this research, a visual pressurized flat-flame reaction system was designed. A particle-tracking image pyrometer (PTIP) system based on a high-speed camera and an SLR camera was proposed. Combining the experimental system and data-processing method developed, the ignition and combustion characteristics of a single coal particle between 69 and 133 μm in size were investigated. The results indicated that at atmospheric pressure, the ignition delay time of ShanXi (SX) anthracite coal was longer than that of ShenHua (SH) bituminous coal, while that of PRB sub-bituminous coal was the shortest. As the pressure rose, the ignition delay time of the PRB sub-bituminous coal and SX anthracite coal showed a continuous increasing trend, while the ignition delay time of SH bituminous coal showed a trend of first increasing and then decreasing. Moreover, pressure also affects the pyrolysis process of coal. As the pressure increases, it became more difficult to release the volatiles produced by coal pyrolysis, which reduced the release rate of volatiles during the ignition stage, and prolonged the release time and burning duration time of volatiles.

A study on the influence of ignition energy on ignition delay time and laminar burning velocity of lean methane/air mixture in a constant volume combustion chamber

This study presents the effect of ignition energy (Eig) on ignition delay time (tdelay) and uncertainty of laminar burning velocity (Su0) measurement of lean methane/air mixture in a constant volume combustion chamber. The mixture at an equivalence ratio of 0.6 is ignited using a pair of electrodes at the 2-mm spark gap. Eig is measured by integrating the product of voltage V(t) and current I(t) signals during a discharge period. The in-chamber pressure profiles are analyzed using the pressure-rise method to obtain tdelay and Su0. Su0 approximates 8.0 cm/s. Furthermore, the increasing Eig could shorten tdelay, leading to a faster combustion process. However, when Eig is greater than a critical value, called minimum reliable ignition energy (MRIE), the additional elevating Eig has the marginal effect on tdelay and Su0. The existence of MRIE supports to optimize the ignition systems and partly explains why extreme-high Eig>> MRIE has less contribution to engine performance.

Determination of Appropriate Operation of Firefighting Facility using Fire and Evacuation Simulations

Recently, a performance-based design of a fire protection facility has been proposed that significantly contributes to the construction of safe and reliable buildings. Improving the performance of the fire protection facility will enable protection of the public along with the infrastructure. Designs focusing on the fire protection performance generally add or modify architectural aspects through fire and evacuation simulations. However, a secure evacuation system aided with CCTVs has rarely been considered as an active system. Particularly for apartments, it is very difficult to assure evacuation safety without using an active system in fire and evacuation simulations with the front door of the burning room open. Safety can be achieved by combining a passive system with an active system, on the basis that the building premises has the foundation of a passive system. The regulation on the evacuation delay time in the nation was brought in effect through the SFPE paper but was deleted since the data reliability was insufficient. Therefore, the aim of the present study is to analyze the operation of a fire protection facility required to ensure safety by planning multiple simulations of a fire and evacuation system. An apartment has been considered as an example to design the foundation for a standard evacuation safety system. An active system is applied to execute fire and evacuation simulations, with focus on the fire protection performance.

Short-Term Deformation Model of High-Performance Concrete Plate Based on Surrounding Temperature

The relationship between surrounding temperature and deformation behaviour of one full scale concrete plate with compressive strength of 60 MPa was presented in this paper. This research was done in Indonesia. Indonesia presents humid tropical weather. A specimen measuring 3.00m × 1.60m × 0.15m was used. Deformation was obtained by using four embedded vibrating wire strain gauges. The range observation is held between 7 to 28 days. The peaks of deformation follow peaks of surrounding temperature. Some deformation peaks time occur after surrounding temperature peak time, it is called as delay time. As a result, there is a linear relationship between temperature and deformation. The relationship was influenced by a factor which presented its position and delay time. The average error of this model is less than 15% at the age range of 7 until 14 days, and less than 50% at the age range of 15 - 28 days.

A Packet Delay Assessment Model in the Data Link Layer of the LTE

The issues of modeling and evaluating the characteristics of the LTE data link layer functioning are considered. Transmitting packets in the data link layer are represented by a probabilistic-temporal graph consisting of two subgraphs. The first subgraph describes the operation of the HARQ protocol, and the second subgraph describes the operation of the ARQ protocol. The first subgraph is nested within the second subgraph. The probabilities of correct reception, non-error detection, and retransmission of packets in the MAC and RLC layers and generating functions of the packet service time based on the HARQ and ARQ protocols are determined. With the help of generating functions, the average value, variance, and coefficient of variation of the packet service time are determined. To calculate the average packet delay time in the LTE data link layer, the type of queuing system is selected, taking into account the coefficient of variation of the packet service time. The analysis of packets' delay time in the network's data link layer is carried out for different values of the intensity of packet arrival and the probabilities of a bit error in the physical layer of the network. For the sustainable functioning of the data link layer of the network, the limit values of the intensity of the arrival of packets are determined for a given probability of a bit error in the physical layer of the network.