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The electron-transport layer in planar perovskite solar cells plays an important role in improving photoelectric conversion efficiency. At present, the main electronic transmission materials in perovskite solar cells include TiO2, ZnO, WO3, ZrO2, SnO2, ZnO2, etc. This work mainly studies the electron-transport characteristics of six different electron-transport layers in perovskite solar cells. Based on the density functional theory, the electron-transport model of a solar cell doped with formamidinium iodide lead compound perovskite under six different electron-transport materials was constructed, and their effective electron mass and the mobility of carriers were obtained by optimizing the structure and theoretical calculation. The results show that the mobility of electrons in TiO2 crystal is slightly higher than that of FA0.75Cs0.25Sn0.5Pb0.5I3 carriers. Because of their high matching degree, it can be reasonably explained that titanium dioxide has been widely used in perovskite solar cells and achieved higher photoelectric conversion efficiency. In addition, the mobility of carriers in WO3 and SnO2 crystals is also high, so they also have great advantages in carrier transport. Due to its abundant, nontoxic, and low-pollution content, TiO2 has become the most widely used electronic transmission layer material for solar cells. Furthermore, we have explored eight new semiconductor materials that have not yet been used in perovskite solar cells as the electron-transport layer. The calculation results show that Ta2O5 and Bi2O3 are promising materials for the electron-transport layer. This study provides a theoretical basis for seeking better electronic transmission materials for solar cells in the future.

Introduction Patients with type 2 diabetes (T2D) receiving premixed insulin often fail to achieve optimal glycemic control. The insulin injection technique (IT) itself may be one of the factors affecting glycemic variability (GV). The aim of this study was to assess the relationship between GV and IT in patients with T2D using premixed insulin. Methods This was a single center, cross-sectional, and self-controlled trial. Patients with T2D using premixed insulin were enrolled as inpatients. The 4-day study consisted of a 2-day patient insulin injection period (days 0 and 1) and a 2-day specialist nurse insulin injection period (days 2 and 3). Patient insulin IT were assessed on day 1 by two independent nurses using a skill-related scale consisting of 15 items, with a maximum score for each item of 2 and a total optimum score of 30. All patients underwent 96-h continuous glucose monitoring (CGM) during the 4-day study, and CGM data collected on days 1 and 3 were recorded and analyzed. The primary outcome was the relationship between the insulin IT score and the 24-h mean amplitude glycemic excursion (MAGE) during the patient injection period. Results A total of 52 inpatients with T2D who used premixed insulin were recruited and completed the study. The mean total insulin IT score of these patients was considerably lower than the optimum score (17.0 ± 4.4 vs. 30). Our CGM data showed that the MAGE was significantly higher during the patient injection period than during the nurse injection period (P

A multiproduct pipeline is an economical way for transporting several products from a single source to multiple delivery stations over a long distance. This paper addresses how to optimize detailed schedules of a multiproduct pipeline. A discrete-time mixed integer linear programming model is developed, which adopts a novel objective function to seek the minimum summation of pumping rate variations in every pipeline segment along a pipeline during a scheduling horizon. The feasibility of the new objective function is demonstrated in theory. A conclusion is drawn that the more stable pumping rate of a pipeline segment is, the lower frictional loss for pumping products is. Besides operational constraints, two sets of special constraints are introduced into the model for improving the operability and practicability of detailed schedules. One is the stopping and running duration limitations of injection operations and another one is the flow rate stability requirements of injection and delivery operations. The proposed MILP model is successfully tested on two real world multiproduct pipelines using CPLEX as solver.

Rational nutritional support shall be based on nutritional screening and nutritional assessment. This study is aimed to explore nutritional risk screening and its influencing factors of hospitalized patients in central urban area. It is helpful for the early detection of problems in nutritional supports, nutrition management and the implementation of intervention measures, which will contribute a lot to improving the patient's poor clinical outcome. A total of three tertiary medical institutions were enrolled in this study. From October 2015 to June 2016, 1202 hospitalized patients aged ≥18 years were enrolled in Nutrition Risk Screening 2002 (NRS2002) for nutritional risk screening, including 8 cases who refused to participate, 5 cases of same-day surgery and 5 cases of coma. A single-factor chi-square test was performed on 312 patients with nutritional risk and 872 hospitalized patients without nutritional risk. Logistic regression analysis was performed with univariate analysis (P

In recent years, perovskite solar cells have attracted the attention of many researchers due to their advantages such as high conversion efficiency, simple manufacturing process and low cost, and have become an important research direction in the field of new energy batteries. At the same time, it is also a very promising new type of solar cells. In this paper, the geometric characteristics, mechanical properties, electronic properties and optical properties of three perovskites In2TiCl6, In2TiBr6 and In2TiI6 were studied by using first-principles. The Poisson and Pugh’s ratios show the ductile characteristics of In2TiX6 (X = Cl, Br, I). The mechanical stability of studied compounds has been confirmed by the Born stability criteria. Moreover, the thermodynamic stability has been proved by the negative formation enthalpy and cohesive energy. In2TiCl6 and In2TiBr6 are indirect band gap semiconductors with band gap values 2.15 and 2.12 eV, respectively, and In2TiI6 is a direct band gap semiconductor with band gap value 1.24 eV. Theoretical calculations showed that In2TiI6 has better absorption capacity than In2TiCl6 and In2TiBr6 in the near ultraviolet and visible light regions. The results demonstrate that the compound In2TiI6 can be a potential candidate for excellent light absorbing material.

FAPbI3(NH2CHNH2PbI3) is an organic-inorganic hybrid perovskite containing Pb, which has good photoelectric characteristics and great potential in the application of low-cost and high energy efficiency photoelectric devices. In order to reduce the pollution of Pb to the environment, the first-principles based on density functional theory(DFT) is used to compare and study the photoelectric parameters such as the band structure, density of states(DOS), absorption coefficient, reflectivity, conductivity and dielectric function of FAPb1−xGexI3(x = 0.0,0.33,0.50,0.67,1.0). The results show that the 4p orbital electrons of Ge and the 6p orbital electrons of Pb and 5p orbital electrons of I are hybridized after doped with Ge, which change the band structure of FAPbI3. The result is that the optical band gap of the material is narrowed, the curvature of the band is increased, the effective mass of electrons and holes is reduced, the absorption peak of visible light increases and the absorption range increases. And the reflectivity and energy loss of the material also increase at the same time. The super SOC effect of the heavy metal Pb element leads to the splitting of the conduction band level of FAPbI3, the conduction band value drops sharply, and the band gap decreases sharply. We found that when the doping ratio of x in FAPb1−xGexI3 was between 0.55 and 0.65, the optimal band gap was between 1.3–1.4 eV. Therefore, reasonable regulation of Ge’s doping ratio can improve the photoelectric conversion efficiency of FAPbI3. This study can provide some theoretical guidance for experimental research and search for new efficient and environmentally friendly perovskite solar materials.

Smart grid, as the next power grid, can efficiently monitor, predicate, and control energy generation/consumption by using the real-time users' electricity information. However, the fine-grained user energy consumption information may reveal the private information of the user. In this paper, we construct a linkable anonymous credential protocol based on Camenisch-Lysyanskaya (CL) signature. Then, we propose a privacy preserving smart metering scheme based on the new linkable anonymous credential. In addition to providing privacy protection for the user, our protocol also has the security properties of message authentication and traceability of fault smart metering. And there are some other useful features in our protocol, such as no need of trust-third party, dynamic users' enrollment and revocation, and complex statistical analysis of the energy use information. The computation cost and communication overhead of our scheme is O(1), which is independent of the user number. The simulation results show that our scheme is efficient.

Carbon dioxide, a greenhouse gas mainly from the consumption of fossil fuel, is regarded as an attractive feedstock in view of synthetic chemistry. Great efforts have been devoted to developing catalytic processes for converting CO2 into value-added compounds with reduced carbon footprint. Among versatile applications in organic synthesis, CO2 can serve as a promising raw material for fuel production, especially methanol. ‘Coming from fuel and returning to fuel’ is an appealing objective in terms of sustainable development associated with circumventing the energy shortage and CO2 issue. To date, metal complexes and organocatalysts for CO2 hydrogenation to methanol have been developed along with the reaction mechanistic insight. Understanding the interaction of active catalytic species with CO2 or hydrogen could account for development of efficient homogeneous catalysts. In this context, homogeneous catalytic hydrogenation of CO2 and its derivatives into methanol is highlighted in this article in combination with mechanistic understanding on a molecular level.

Establish the mechanical model of wire knot which was formed by the automatic bundling machine, and the model is simulated by ANSYS. The method can simulate testing and evaluation the strapping characteristics, thus can provide the support to design and use bundling machine properly as well as improve the strapping quality of automatic bundling machine.

In this paper, we discuss the cooperation behaviors of intelligent virtual agents with autonomous and cooperative ability .Based on the theory of fluent calculus, we have designed an agent reasoning model .In this model, intelligent virtual agent could automatically judge the next action in the action queue and constructs the dynamic environment quickly with limited information from sensor. Furthermore, a type of request/server cooperation function has been designed for the cooperation among virtual agents to solve the conflicts and to realize the joint goals. Experiment results obtained demonstrated that intelligent virtual agents could cooperate well by our reasoning model.

In order to solve the problems that diagnosis cycle is very long and diagnostic accuracy is very low dependent on the maintenance man to diagnose fault by experience, an expert system for fault diagnose of a planes airborne electronic devices based on VC++ and CLIPS is proposed. The information exchange is realized between VC++ and CLIPS through writing external function of CLIPS by VC++ platform. The fact base can be generated quickly through acquiring test parameters from test model according to the fault information template base. The expert system established by VC++ platform to write man machine interface codes and load CLIPS to realize fault reasoning can realize the fast fault diagnosis for the airborne electronic devices.

In order to solve the problems that measuring efficiency is low and measuring precision is low dependent on the maintenance man to test by manual work, a universal high precision tester of attack and slide angle sensor is proposed. The measuring efficiency has improved through the electronic spirit level that measures the attack and slide angle fast and automatically and reads data automatically. The universal property and expansibility is realized by the design method that the software and test data are designed separately. The tester in this paper is fit for the fast maintenance requirement of the attack and slide in the army, and this method has certain reference to construct other electronics tester.

A design idea of calcium tester based on embedded platform is described. The composition of calcium test system is firstly analyzed. Secondly, in the acquisition of the potential signal of solution concentration the model of a sensor system is introduced. Finally the realization technique of tester is chiefly discussed in hardware and software.

The performance of the braking system has an important influence on the safe operation of the train. In this paper, the AMESim simulation software is used to simulate the pneumatic valve unit (PVU) for the direct electro-pneumatic braking system controlled by the microcomputer. And the correctness of the model is verified by the simulation of the service braking and the emergency braking. At the same time, the vehicle dynamics model is built in the MATLAB/Simulink environment, and the AMESim pneumatic valve model is combined with the simulation to verify the effectiveness of the anti-skid logic. The simulation results from the service braking and emergency braking can be drawn that the PVU for the direct electro-pneumatic braking system controlled by the microcomputer is consistent with the response of the real system, which verifies the correctness of the PVU model. It can be seen from the simulation results that the anti-skid control logic can achieve the control requirements, and can achieve the stability of the anti-skid effect in the event of a continuous sliding. The results of this study provide an effective model base for the design of the actual vehicle braking system and solutions to the fault.

Carbon capture and storage/sequestration (CCS) is now being considered as a potential option to mitigate global warming associated with carbon accumulation. The chemical absorption technique employing efficient amino-containing absorbents has been widely developed. Nevertheless, extensive energy consumption in desorption–compression process would be a crucial barrier to realize practical CCS. On the other hand, CO2 is very attractive as a typical renewable feedstock for manufacturing commodity chemicals and fuels. However, the reactions involving CO2 are commonly carried out at high pressure, which may not be economically suitable and also pose safety concerns. Consequently, we have proposed a carbon capture and utilization (CCU) strategy as an alternative approach to addressing energy issue in CCS. This crucial point of CCU could be simultaneous activation of CO2 upon its capture (e.g., formation of carbamate/alkyl carbonate) and thus in situ catalytic transformation into value-added chemicals under mild conditions, avoiding additional desorption step. This chapter is intended to discuss carbon capture and in situ transformation of CO2 to oxazolidinones, carbonates, quinazolines, urea derivatives, isocyanates, and carbamates via the formation of C O and C N bond.

Obfuscation was first studied in computer programming field, which could be explained as a compiler that translates computer codes into an unintelligible form while preserving the original functionality. Since obfuscation for cryptographic purposes was raised out, several positive results have been presented in despite of the general impossibility. Secure obfuscation of point functions have been studied well and it was pointed out that secure composition of several point function obfuscation could realize the secure obfuscation of set-membership predicate function. However, secure composition of point function obfuscation was only proposed in one literature and the security was proved in Generic Group Model(GGM) under the definition of Virtual Grey Box-Obfuscation(VGB). In this paper we propose a new obfuscation construction of set-membership predicate functions under the standard definition of Virtual Black Box-Obfuscation(VBB). We utilize the vector space technique instead of obfuscation composition, and the security of obfuscation relies on an assumption which exists in standard model. Moreover, our obfuscation result of set-membership predicate functions can hide the real scale of the set and the obfuscation construction can be securely composed for different sets.

In order to speed up the intelligence and automation of the steering system, the principle of the potentiometer are deeply analyzed in the paper, and then its two application approaches are also discussed in detail for the steering system of vehicle. The first approach is for the potentiometer to apply in the traditional steering system, in which there is not controller based on a micro-processor, and the system performs its steering tasks only by the differential output of the double potentiometers. The second approach called as steer-by-wire is finally presented, in which one potentiometer is used for collecting the steering signal from the driver, the other one used for collecting the pinion angle signal of the steering gear, and these signals are all input into a controller for a precise and safe steering. The final investigation result shows the potentiometer will do more important role in the future steering system, and its successful application can excite the more fast innovation of the steering system.