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Aiming at the issues of poor system resource utilization and the challenge of ensuring the quality of service (QoS) in scientific workflow scheduling in the current cloud computing environment. By combining the existing IaaS cloud resource model with the scientific workflow task model, the article proposed a cloud workflow scheduling model framework. Firstly, proposed multi-objective QoS constraints based on the execution time and costs in scientific workflow scheduling. Then, modified the HEFT algorithm which was a typical scientific workflow scheduling algorithm. Based on the modified HEFT algorithm makes full use of the idle time of resources and maximizes the multi-objective QoS requirements of users. The comparative experiments show that the scheduling strategy of the modified HEFT algorithm can effectively optimize the costs and execution time of scientific workflow scheduling and achieve higher system resource utilization.

We systematically investigate the mass spectrum, spatial configuration and magnetic moment of the ground and p-wave states [ c u ] [ c ¯ s ¯ ] with various color-spin configurations in a multiquark color flux-tube model. Numerical results indicate that the state Zcs (4000)+ can be described as the compact state [ c u ] [ c ¯ s ¯ ] with 13S1. Its main color-spin configuration is [ c u ] 6 c 1 [ c ¯ s ¯ ] 6 ¯ c 1 and its magnetic moment is 0.73μ N. The state Z c s ( 4220 ) + can be depicted as the compact state [ c u ] [ c ¯ s ¯ ] with 11 P 1 (or 13 P 1). Its main color-spin configuration is [ c u ] 3 ¯ c 0 [ c ¯ s ¯ ] 3 c 0 (or [ c u ] 3 ¯ c 0 [ c ¯ s ¯ ] 3 c 1 ) and its magnetic moment is 0.12μ N (or 0.64μ N). The physical state should be the mixture of these two different color-spin configurations and deserves further investigation. In addition, we also predict the properties of the states [ c u ] [ c ¯ s ¯ ] with other quantum numbers in the model.

Whispering-gallery mode (WGM) cavities formed by dielectric structures have attracted intensive interest in various fields. The high-quality factor and smaller mode volume associated with the optical modes have inspired experiments in nonlinear optics, nanophotonics, and quantum information science. Moreover, they are also used in optical biosensors and other significant applications. To further reduce the material loss of the resonator, optical gain materials, such as erbium and ytterbium, are doped into the dielectric structure to increase the nonlinear effect and enhance the interaction between light and matter. Here in this review, we outline the most recent advancements in gain-doped optical WGM microcavities. Moreover, we introduce the dynamics of the gain in WGM resonators, the integration of gain media into WGM microcavities with various shapes, and the fabrication and applications of the gain microcavities. Also, the applications of the gain cavity based on the whispering-gallery mode have been introduced, e.g., ultra-sensitive sensors, low-threshold lasers, and high-performance optical systems.

Based on the deep-water high temperature and high pressure LS25 gas field in the Nanhai Reservoir, through the design of heterogeneous formations and the design of water control experimental schemes, physical simulation experiments of different gas reservoir water control processes have been completed, focusing on evaluating the variable density compound water control technology based on continuous packers. In terms of the adaptability of deep-water gas reservoirs, on this basis, combined with the experiment-mine scale conversion method, a water-controlled exploitation plan for deep water high-temperature and high-pressure gas reservoirs is given. The experimental results show that: (1) Under elastic production conditions, the water body of the bottom water in the gas reservoir rises in a “progressive” manner in the initial stage, and generally develops in a “cone progression” in the middle and late stages. (2) There are obvious differences in the effects of various water control processes. A single continuous sealing body has no obvious effect on bottom water control during the gas production period of a gas well, and a single variable density screen process has no obvious effect on water control in the early stage of gas well production. The effect is good, but the risk of water channeling cannot be avoided after the gas well breaks through. The experimental effect of the variable density composite water control process based on the continuous packer is good, and the bottom water coning effect has changed to a certain extent. The experiments show that the water-free gas production period of the composite water control process is 13.7 years, the total gas production time is extended to 15.8 years, the total gas production after water control is as high as 12.37×108m3, and the recovery rate of gas wells is 9.2%, which is higher than that of elastic production. The research results aim to establish an optimal water control development model for high temperature and high-pressure deep water gas reservoirs and provide a good technical support for rational and scientific research on water control in horizontal wells of offshore deep water gas reservoirs.

Carbyne, the linear chain of carbon, promises the strongest and toughest material but possesses a Peierls instability (alternating single-bonds and triple-bonds) that reduces its strength and toughness. Herein, we computationally found that the gravimetric strength, strain-to-failure, and gravimetric toughness can be improved from 74 GPa⋅g−1⋅cm3, 18%, and 9.4 kJ⋅g−1 for pristine carbyne to the highest values of 106 GPa⋅g−1⋅cm3, 26%, and 19.0 kJ⋅g−1 for carbyne upon hole injection of +0.07 e/atom, indicating the charged carbyne with record-breaking mechanical performance. Based on the analyses of the atomic and electronic structures, the underlying mechanism behind the record-breaking mechanical performance was revealed as the suppressed and even eliminated bond alternation of carbyne upon charge injection.

Realizing fast and accurate quench detection is a great challenge for the application of long high-temperature superconducting (HTS) conductors. The combination of a distributed temperature sensing (DTS) system and optical fiber-encapsulated HTS (OFE-HTS) tape may become a promising approach to solve this problem. As a recently proposed composite HTS tape, its properties have not been studied systematically yet. Therefore, in this study, the electromagnetic and thermal behaviors of the OFE-HTS and traditional HTS tapes are compared by finite element simulation technology. The simulation results predict that the embedded optical fibers will hardly change the original electric, magnetic and thermal characteristics of the HTS tapes. In addition, a detailed fabrication method for OFE-HTS tape is introduced, and the composite tape performances including structural integrity, critical current uniformity, anti-bending/tensile force and quench response are tested seriatim. According to the microscope and x-ray detection results, the optical fibers are fully embedded in the OFE-HTS tape through the presented fabrication process. The critical current uniformity test results show the average critical current of the prepared 76 m long OFE-HTS tape is about 520 A, and the uniformity variation is about ±4%. The prepared OFE-HTS and traditional tapes have similar anti-bending/tensile properties. Finally, to check the effectiveness of the embedded optical fiber for quench detection, the fabricated OFE-HTS coil is tested. The quench detection results show that the temperatures in the same area measured by the optimized DTS system and a thermocouple are similar. Moreover, the temperature response ability of the optimized DTS system is better than that of the thermocouples, and the optimized DTS system is able to effectively avoid environmental electromagnetic field interference.

To describe the dynamic response characteristics of the laminated graded-bandgap GaAs-based photocathode with distributed Bragg reflection structure, a general theoretical temporal response model is deduced by combining the unsteady continuity equation and numerical calculation method. Through the model, the contribution of the distribution Bragg reflection structure and graded-bandgap emission layer to the temporal response are investigated. Meanwhile, the relationships between the temporal response characteristics of the laminated GaAs-based photocathode and different structural parameters are also analyzed, including average electron decay time, emission layer thickness, and incident light wavelength. It is found that the introduction of distribution Bragg reflection (DBR) layer solves the discrepancy between the absorption capability of the emission layer and the temporal response. Moreover, the distributed Bragg reflection layer can improve the time response by optimizing the initial photoelectron distribution. The improvement effect of the DBR layer on the temporal response is enhanced with the emission layer thickness decreasing or the incident light wavelength increasing. These results explain the effect of the DBR layer of the photocathode on the dynamic characteristics, which can offer a new insight into the dynamic research of GaAs-based photocathode.

Vertical GaN trench-gate MOSFETs with ∼130 nm stepped sidewalls in the p-GaN channel layer are studied and two significant influences have been observed compared to the devices with smooth sidewalls. The first effect is the degraded channel mobility of 14.6 cm2 (V·s)−1 to 4.5 cm2 (V·s)−1 which can be attributed to the increased probability of surface acoustic phonons scattering under inversion conditions. Another impact is that only when a drain voltage (V DS) is applied over 30 V can the devices switch on. It can be speculated that the stepped sidewall has a horizontal channel and the transverse electric field is inadequate to drive the electrons at low V DS. According to the investigation, when devices need to be switched at a high V DS, the stepped sidewall morphology should be taken into consideration.

The frosting of the evaporator of the ship’s low-temperature cold storage will affect the heat exchange performance of the evaporator operation, the stability of the low-temperature cold storage of the ship’s food security and the effect of food refrigeration. Therefore, the evaporator coil of the low-temperature cold storage needs to be defrosted regularly. The low-temperature refrigeration system of a ship adopts the defrosting mode of electric heating. The lower the temperature of the low-temperature warehouse, the more important the thermal effect of defrosting is. This paper puts forward a technical innovation scheme for the design of the ship’s cold storage and the defrosting control mode, which can provide a reference for the design of the ship’s low-temperature refrigeration system and the defrosting of the low-temperature cold storage.

This paper introduced the components and functions of control components of a ship automatic power station, with an analysis of the control principle of such station. The fault treatment method and troubleshooting process are elaborated based on mechanical overspeed automatic shutdown fault of the generator. Finally, in view of the problem of 4K6 relay, appropriate improvement measures are proposed.

Information asymmetry on energy efficiency target between enterprises and governments is a major controversy about sustainability. Enterprises desire to pursue the maximum profits in the market while governments confront with incomplete information on energy intensity potential and policy implementation. To investigate the influence of information gap between them, this study uses two-tier stochastic frontier (TSF) model with scaling property on the panel data in 56 contracting countries in Kyoto Protocol from 1995 to 2014 on energy intensity from energy, economic and technological perspective. The results present that on average about 70% of the unexplained variations in energy intensity accounts for the influence of energy intensity gap on energy savings potential between enterprises and governments. And the actual energy intensity is upper biased by average 7.03% due to the information asymmetry although the net impacts differ slightly across developing and developed countries and over time. Enterprises have stronger influence on the energy intensity during sample period. We recommend developing countries’ governments to have a strong renewable energy governance framework to support urbanization for economic development is their backbone for long period.

In order to ensure the high-quality operation of urban traffic, the impact of rainfall on urban road characteristics was studied. Taking Zhengzhou as an example, the traffic volume, headway time and vehicle start loss time under different rainfall were counted. By studying the mechanism of the basic capacity and actual capacity of roads affected by rainfall, the changes in the degree of impact of rainfall on roads and other traffic environments are determined.

With the development of the times, the demand for high efficiency and reliability of machine performance in China’s industry has become higher than ever before, and the traditional equipment condition evaluation method has also encountered a huge challenge. As an important branch of machine learning, cluster analysis is widely used in fault diagnosis and other fields because of its advantages of no prior knowledge and massive data processing. This paper introduces the concept of principal component analysis and K-means method based on time series in the field of oil data analysis. Through the test data on the oil monitoring data of the steam turbine unit in the power plant, the condition evaluation and classification of the equipment are carried out, among which the classification effect of 6μm particles, dielectric constant and 4μm particles is very obvious, and the water content is relatively obvious, which can basically distinguish each state. At the same time, on the basis of feature extraction, use the special cyclic neural network (RNN) in deep learning-long and short-term memory network (LSTM) to build a model of data for data prediction, under the powerful ability of LSTM to process temporal data, they have unearthed more irregular and non-linear trends in a large amount of historical data, and achieved better prediction results than traditional methods (ARIMA). Through clustering and prediction of lubrication parameter data, it can realize early warning and abnormal diagnosis of lubrication status and reduce damage to machinery and equipment.

From the perspective of low carbon logistics, we take into account the environmental costs caused by the carbon emissions of battery electric vehicles. In addition, according to the customer’s certain requirements for the delivery time during the actual delivery process, this paper introduces the penalty cost of the time window, thus constructing a delivery route optimization model with the goal of minimizing the total delivery cost. Then, this problem is solved by using the Ant Colony Algorithm. Finally, the case design is used for empirical analysis.

The realization of the virtual laboratory includes the construction of the website and the design of the learning system. The design of the learning system is introduced in this paper. In the system, the popular EDA tool Quartus EDA ModelSim is used to construct the virtual experimental environment, and the virtual FPGA is used as the carrier. EDA is used to design, modify, debugs and verifies the circuit. As a learning tool for digital circuit design and experimental simulation verification, it has obvious advantages. The course, theory and technology involved in the teaching of digital circuits are integrated to form a virtual experimental teaching simulation platform for digital circuits which is rich in content, advanced in technology, theory, experiment and simulation, and enriches the teaching methods. The paper presents research and Design of Digital Logic Virtual experiment system.

Aiming at the problem of automobile exhaust pollution and the measures of urban traffic restriction, this paper introduces the traffic restriction conditions into the vehicle path problem. Firstly, the speed characteristic models of different road conditions are established. Then, aiming to minimize the total cost such as carbon emission and distribution cost in the distribution process, a multi-energy and multi-vehicle hybrid vehicle path optimization model is constructed under traffic restrictions. Finally, an improved adaptive genetic algorithm is proposed based on the idea of simulated annealing. The effectiveness of the model and algorithm is verified by simulation experiments and examples.

FPGA is the abbreviation of Field Programmable Gate Array. The corresponding CPLD is the abbreviation of complex Programmable Logic device. So sometimes the difference can be ignored, collectively called programmable logic devices or CPLD/PGFA. FPGA has a universal structure of masked programmable gate arrays, which is arranged by logical function blocks and connected by programmable interconnection resources to implement different designs. The basic function of a digital electronic clock based on FPGA is designed, simulated and realized by using digital electronic technology, such as FPGA and so on.

For the 8bit MCU of RISC architecture which is widely used at present, the internal resources such as Rom Ram stack are all limited. If written in C language, a C language instruction will become a lot of machine code after compiling, and it is easy to find that the ROM space is not enough. Stack overflow, etc. One of the biggest advantages of C is that it has nothing to do with any particular hardware or system. This allows a user to write programs that run on almost all machines without any modification. This paper presents an embedded C language target code level unit test method based on CPU simulator.

The introduction to broadband micro-power wireless technology in the national network intelligent meter reading system can increase the bandwidth, improve the meter reading performance, and make up for the narrow bandwidth and low speed in narrow-band micro-power wireless and PLC technology. In the smart meter reading network, the generation and maintenance of routes are the key. This paper improves the AODVjr algorithm and improves it from full-network broadcasting to semi-directional directed broadcasting, calculating channel quality based on weight, making it suitable for real-time routing repair in broadband micro-power wireless intelligent meter reading. The improved algorithm minimizes route repair time and routing overhead while ensuring communication success rate. The simulation results show that with the increase of the number of nodes, the semi-directional broadcast has much better performance in routing request packet transmission success rate, average hop count, communication success rate, and route repair delay than the whole network broadcast.

The grain combine harvester is the most important grain harvesting machine in China. The lack of adaptability of domestic harvesters to different planting habits in different regions of China is an urgent problem to be solved. This paper proposes and mechanically designs and constructs the structure for the automatic detection of grain planting spacing by the harvester, and realizes the automatic control of the plant by PLC technology, thus realizing the automatic measurement of the grain spacing of the grain harvesting machine by the harvester.

In order to improve the working efficiency of the grain combine harvester, this paper decomposes the harvester into three parts: the power system, the walking system and the operating system. The paper determines the matching relationship between engine power and driving speed, corn harvesting speed, peeling speed and threshing speed. This paper determines the mathematical model of the main working parts by establishing a matching relationship. Based on the mathematical model, this paper designs the harvester simulation model by using Matlab and simulink software tools. In this paper, the effects of engine power simulation parameters on the speed, threshing and harvesting speed of the harvester in the mathematical model are studied. The results show that the harvester power increases, the walking speed of the harvester increases, the harvesting speed increases, the speed of corn peeling and threshing increases, and the loss of corn in threshing and clearing increases. The mathematical model of the harvester is very high and belongs to the large inertia system.

An integrated vertical cavity semiconductor optical amplifier (VCSOA) and PIN photodetector was proposed in attempting to raise the sensitivity in high speed fiber-optic communication systems. Two slightly different structures have been studied under this configuration. For the cascade and the resonance structure, our simulation results showed that their sensitivity could reach -33dBm and -36dBm at a bit rate of 10Gb/s, respectively. We also managed to fabricate the cascade structure and demonstrated a 7dBm improvement on sensitivity as compared to the conventional PIN photodetector.

The grain combine harvester is a large and complex agricultural machine, and the transmission system is an important part of the combine harvester. The effect of the transmission system has a significant impact on the performance of the combine harvester. Hydraulic systems play an increasingly important role in harvester drive systems. The body leveling hydraulic system generally has overflow loss and heavy throttling loss leading to hydraulic energy loss. There is a power mismatch between the power source and the load, and the power mismatch causes the energy loss problem. At present, there is less research on the leveling of harvesting locomotives in China. In this paper, reasonable power matching is carried out for the components of the grain combine harvester body, and the hydraulic drive scheme of the functional module that meets the requirements is designed. The parameters of the hydraulic system are optimized by AMESim simulation software, and the subsequent combine harvester drive System design provides a reference.

The combine harvester header is an important part of the whole machine design. The design of the hydraulic system of the header is the key to realize the hydraulic control part of the whole system. In this paper, AMESim is simulated on the combined harvester header lifting hydraulic system. Through the curve of the flow rate and displacement of the lifting hydraulic system of the header of the combine harvester, the movement process of the header is carried out. This paper studies the effect of different pump speeds on the working efficiency of the header lifting in the header hydraulic system. The simulation results verify that the designed hydraulic system can meet the hydraulic pressure range of the header during the harvesting process. The research in this paper provides a reference for the hydraulic design of the header of a similar combine harvester.

This paper proposes a green energy-saving maintenance room.The maintenance room can solve most of the problems faced by most cement product curing rooms during use. For example, poor insulation performance and low level of automation.according to the specific requirements of the maintenance of room temperature and humidity, a cement room temperature and humidity control system was designed to detect and control the temperature, humidity and other parameters of the cement product curing room. The temperature field during the operation of the green energy-saving room through ANSYS was analyzed. The results showed that the optimum temperature of solar hot air blowing in the curing room was 70°C.

Proton radiography is a new tool for advanced hydrotesting. This article will discuss the basic concept of proton radiography first, especially the magnetic lens system. Then a scenario of 50 GeV imaging beamline will be described in every particular, including the matching section, Zumbro lens system and imaging system. The simulation result shows that the scenario of imaging beamline performs well, and the influence of secondary particles can be neglected.

An overall irradiation and calibration technique was introduced and applied to a test scintillation detector array. An integral conversion method was used to reduce the nonlinearity of the time difference spectrum, and to improve the position determination especially for positions close to the two ends of a long scintillation bar. An overall position resolution of about 3.0 cm (FWHM) was extracted from the residual analysis method and verified by a direct measurement. Energy calibration was also realized by selecting cosmic rays at different incident angles. The bulk light attenuation lengths for the four test bars were also determined. It is demonstrated that these methods are especially efficient for calibrating large and complex detector arrays.

The threshing and cleaning process of combine harvester is easy to break down, so it is necessary to monitor it automatically. This paper takes PLC as the core controller, through the touch screen designing man-machine interface. The hardware and software is designed, and the automatic monitoring system for threshing and cleaning of combine harvester is developed. Threshing and cleaning work parameters is early warned and controlled, and the experimental platform is built to verify the validity and rationality of the system development.

When combine harvester is used in the field, the load is difficult to be stabilized due to the complex environment. Based on the analysis of the cylinder power model, this article identifies the factors that affect load stability. We calculated and studied the fuzzy control of the cylinder load. Cylinder two-dimensional fuzzy controller is established through the Matlab, and the cylinder fuzzy control model is set and simulated through the Simulink, which results prove that the fuzzy control of harvester load stability is accurate and effective.

In the case of rapid development of wind power and heavy wind curtailment, the study of wind power accommodation of combined heat and power system has become the focus of attention. A two-stage scheduling model contains of wind power, thermal energy storage, CHP unit and flexible load were constructed. This model with the objective function of minimizing wind curtailment and the operation cost of units while taking into account of the total coal consumption of units, constraint of thermal energy storage and electricity-heat characteristic of CHP. This paper uses MICA to solve the problem of too many constraints and make the solution more feasible. A numerical example showed that the two stage decision scheduling model can consume more wind power, and it could provide a reference for combined heat and power system short-term operation

The main bottlenecks in the development of current embedded phase change memory (PCM) technology are the current density and data storage density. In this paper, we present a PCM with 4F2 cross-point diode selector and blade-type bottom electrode contact (BEC). A blade TiN BEC with a cross-sectional area of 630 nm2 (10 nm × 63 nm) reduces the reset current down to about 750 μA. The optimized diode array could supply this 750 μA reset current at about 1.7 V and low off-current 1 × 10−4 μA at about −5.05 V. The on-off ratio of this device is 7.5 × 106. The proposed nanoscale PCM device simultaneously exhibits an operation voltage as low as 3 V and a high density drive current with an ultra small cell size of 4F2 (108 nm × 108 nm). Over 106 cycling endurance properties guarantee that it can work effectively on the embedded memory.

Positronium (Ps) formation cross sections (n=1, 2) in positron-hydrogen collisions for various Debye lengths from the Ps formation thresholds to 40 eV are calculated using the screening approximation model, taking account of the influence of the plasmas screening on the Coulomb potentials and the structures of target states and Ps states. The influence of considering modified bound-state wave functions and eigenenergies for the Ps by the screened Coulomb potential on the Ps formation process is investigated.