bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance analysis and SINR‐based power allocation strategies for downlink NOMA networks
Authors: Baidas Mohammed W. , Alsusa Emad , Hamdi Khairi A.
Published: June 2019

This study analyses the performance of downlink non‐orthogonal multiple‐access (NOMA) networks over independent but not necessarily identically distributed Rayleigh fading channels by deriving closed‐form expressions for the average signal‐to‐interference‐plus‐noise ratio (SINR), average achievable rate, and outage probability of all network users. Moreover, SINR‐based power allocation strategies are studied. Specifically, the optimisation problems of max–min SINR, multi‐objective SINR, sum‐SINR and proportional‐fairness‐SINR maximisation under minimum SINR constraints are formulated and shown to be non‐convex. Additionally, the problems of total power and sum‐SINR minimisation are also formulated. Particularly, the formulated problems take the form of linear‐fractional programming problems. By applying intelligent reformulation techniques, these problems have been reformulated into convex optimisation problems, and thus efficiently solved. Numerical evaluations are presented to validate the derived closed‐form expressions for the different performance metrics, which are found to be in agreement with the network simulation results. More importantly, it has been demonstrated that the user with the best channel conditions achieves full diversity order, whereas all the other users achieve diversity orders equivalent to their ordered channel conditions. Finally, the reformulated power allocation strategies are evaluated, and shown to coincide with the original problem formulations.
Energy efficient clustering and secure routing using reinforcement learning for three‐dimensional mobile ad hoc networks
Authors: Muneeswari B. , Manikandan M.S.K.
Published: June 2019

Mobile ad hoc network (MANET) comprises a set of wireless nodes that provide communication benefits for users without any access points or centralised control. Owing to the highly dynamic wireless nature, MANET has many challenges such as limited energy, packet loss, and security. Therefore, a special energy efficient and secure routing protocol is of great importance in MANETs. In this study, three‐dimensional (3D) MANET is considered where mobile nodes are distributed and moved within 3D space. The energy consumption (EC) and throughput increases in the 3D environment compared to 2D. Initially, cell clustering is performed by node residual energy, distance, and mobility in which a cumulative fitness value is computed using the firefly algorithm (firefly with cyclic randomisation algorithm). Then introduced a novel routing scheme referred to as two‐hop relay selection by multi‐metric based reinforcement learning algorithm. Multi‐metric considered for routing is the following: node delay, node distance, node stability, node mobility, and node degree. Before transmission, data packets are encrypted based on the robust cipher watermarking scheme (watermark generation, embedding, and extraction). An extensive simulation is conducted using NS3.26 under a 3D environment in terms of packet delivery ratio, end‐to‐end delay, routing packet overhead, EC, and security strength.
Mapping strategy for virtual networks in one stage
Authors: Cao Haotong , Wu Shengchen , Guo Yongan , Zhu Hongbo , Yang Longxiang
Published: June 2019

In the area of network virtualisation, virtual network embedding (VNE) refers to the resource allocation problem. In the literature, researchers have proposed multiple VNE algorithms. These algorithms have the goal of accommodating as many requested virtual networks (VNs) as possible. However, most of prior embedding algorithms belong to the two‐stage (separated node and link embeddings) mapping algorithm category. Certain embedding algorithms embed each VN in one mapping stage by using mixed integer linear programming approach or graph theory, having very high computation time. There is a lack of heuristic algorithms, enabling to embed nodes and links per VN in one mapping stage. In addition, each requested VN embedding needs to be completed in polynomial time so as to be promoted to future dynamic VN service application and real‐time VNs embedding. Based on these backgrounds, the authors propose a novel real‐time and one‐stage heuristic mapping algorithm (VNE‐RTOS). Numerical evaluations are conducted to strengthen that VNE‐RTOS earns more embedding revenues by 8% over typical two‐stage heuristic embedding algorithms (e.g. VNE‐TAGRD) while achieving the same substrate resource utilisation.
Robust disturbance rejection controller for systems with uncertain parameters
Authors: Zachi Alessandro R.L. , Correia Carlos Alberto M. , A. Filho Jair Luiz , Gouvêa Josiel A.
Published: June 2019

This work proposes a mathematical solution for plants with full set of uncertain parameters which is based on the active disturbance rejection control method. This method has been studied for three decades and its main characteristic is the use of an extended state observer to estimate the non‐measurable signals of the plant. However, the application of the basic methodology requires the exact knowledge of the system control gain, which is difficult to measure in the case of parametric uncertainties. Recently, some advances have been discussed in the literature. Some results have revealed the capability of them of rejecting the unknown input disturbance and of ensuring the stability of closed‐loop transfer functions, even in the case of unknown order and/or relative degrees. However, such proposals have not been effective for large level of parametric uncertainties. The idea of the present work is to relax the requirement of exact knowledge of plant parameters by proposing modifications in the control structure. Mathematical analysis show that the proposed modification does not affect the original purpose of output tracking. The performance of the proposed strategy is compared with other schemes by using numerical simulations. In addition, experimental results on a real cart‐pendulum system are presented.
Adaptive neural network tracking control for switched uncertain non‐linear systems with actuator failures and time‐varying delays
Authors: Hou Qinghua , Dong Jiuxiang , Xi Changjiang
Published: June 2019

This study focuses on the problem of adaptive neural network (NN) tracking control for a class of strict‐feedback non‐linear switched systems under arbitrary switching. The considered systems are with unknown external disturbances, time‐varying delays, and actuator failures. NNs are used to approximate unknown functions and Lyapunov–Karsovskii functionals are utilised to compensate for the time‐varying delays. Different from the existing results, piecewise switched adaptive laws are proposed for each subsystem, which can reduce conservativeness caused by using common adaptive laws for all subsystems. Besides, prescribed performance bound (PPB) technique is developed to further improve the transient performance of the systems, especially when actuator failures occur and system switchings take place. Finally, under the framework of Lyapunov theory, an adaptive NN reliable tracking control method is proposed. It is proved that all the signals in the closed‐loop system are semi‐globally uniformly ultimately bounded and the tracking error remains within the PPBs. A simulation study is given to illustrate the effectiveness of the authors' results.
Framework for real‐time short‐term stability assessment of power systems using PMU measurements
Authors: Safavizadeh Arash , Kordi Meysam , Eghtedarnia Fariborz , Torkzadeh Roozbeh , Marzooghi Hesamoddin
Published: June 2019

Development of phasor measurement units (PMUs) and wide‐area measurement systems in power systems has enabled transmission system operators to monitor and assess the performance of their grids in real‐time. In this study, a new practical method is proposed and prototyped for real‐time monitoring of transient and short‐term voltage stability using synchrophasor data obtained from PMUs. In the previous related studies, methods for detecting rotor angle and voltage instabilities were presented regardless of how they can be implemented and exploited in real settings. In this study, the authors present a framework considering practical concerns, such as noise of measurements and software requirements. The well‐known Lyapunov exponent (LE) concept is used in the heart of the authors’ methodology. Their methodology uses time‐series data obtained from PMUs for calculating LEs, and by averaging the latest data packages received in the control centre, the performance of their framework is significantly improved under noisy measurements. As the framework is mission‐critical, they considered a suitable architecture merged with a flexible human–computer interaction with the goals of increasing security, reliability, resilience, robustness, and efficiency. Simulation results demonstrate the capability of their framework in fast and accurate assessment of short‐term stability using the IEEE 9‐bus and 69‐bus test systems.
Faulted feeder identification in active grounded networks
Authors: Hagh Mehrdad Tarafdar , Rezaei Hossein , Daneshvar Mohammadreza
Published: June 2019

High impedance grounding systems offer great service continuity by limitation of fault currents during single line to ground faults. Recently, a new power electronic based grounding system has been presented, in which an adjustable current was injected into the neutral point. This active grounding system operates as a high impedance grounding system to reduce fault currents, as well as induced over‐voltages. Identification of faulted feeder in a substation with some outgoing feeders from point of common coupling is a general issue in high impedance grounded networks. As a solution to this problem, this study proposes a new approach, to utilise the current injection capability of active grounding systems for detecting the faulted feeder while limiting the fault currents to an acceptable range. The proposed approach does not require any additional devices for faulted feeder detection. Moreover, it is able to identify the ground faults on the main bus. The proposed method is tested on two systems with different capacitive charging currents. Simulation results approve the high efficiency of the proposed method in faulted feeder identification.
Two‐stage nested bilevel model for generation expansion planning in combined electricity and gas markets
Authors: Cong Hao , Wang Xu , Jiang Chuanwen
Published: June 2019

The growing utilisation of natural gas and renewable energy resources brings more challenges to generation expansion planning problems. Short‐term operational constraints are equally important for long‐term capacity planning. This work studies the interdependence between electricity and natural gas systems and presents a combined market mechanism that allows two‐stage energy trading and planning based on asynchronous electricity and gas markets. In the first stage, the gas market is cleared with the objective of maximum social welfare (lower level), at the same time obtaining the optimal strategies offered by gas producers and gas‐fired units (upper level). In the second stage, generation companies and consumer companies aim to maximise their corresponding profits in the planning horizon (upper level), and electricity market is cleared on principle of maximum social welfare (lower level). Then, the authors develop a modified alternative direction method of multiplier algorithm to solve the two‐stage nested bilevel model. To improve operational flexibility of expansion plans, uncertainties of renewable energy generation and integrated demand response are also included and analysed in different risk scenarios. Case studies validate the effectiveness of the proposed methodology.
Metal‐assisted chemical etching for realisation of deep silicon microstructures
Authors: Zarei Sanaz , Zahedinejad Mohammad , Mohajerzadeh Shams
Published: June 2019

Metal‐assisted chemical etching process is exploited to realise deep‐etched silicon structures. Gold as the noble metal, hydrogen peroxide and hydrofluoric acid solutions are used to achieve deep vertical structures. By controlling the solution concentrations, thickness and morphology of the deposited metal, several hundred micrometre‐sized silicon structures can be achieved. This method, upon achieving more controllability and repeatability, can be a good substitute for dry etching, due to its high etch‐rate, low‐cost materials and non‐requirement to complex equipment. In this work, the effect of different etching parameters on the etching process is studied to gain more control over the etching conditions.
Correlation between the formation of particle defects on sputtered Cu seed layers and Cu targets
Authors: Bian Yi‐Jun , Cha Ming‐Yang , Chen Lin , Sun Qing‐Qing , Zhang Wei , Ding Shi‐Jin
Published: June 2019

For advanced copper (Cu) interconnection applications, this work investigated the influence of impurity particles in the Cu target on the formation of particle defects on the sputtered Cu film. By using a liquid particle counter detection system and X‐ray photoelectron spectroscopy, the properties of the impurity particles in the Cu targets were characterised. It is revealed that the impurity particles in the Cu target contain 98.5% carbon, and around 75% impurity particles have a size <1 μm and about 10% ones have a size larger than 2 μm. Subsequently, the correlation between carbon particles in the Cu target and particle defects on the sputtered Cu film is explored. For the carbon particles larger than 0.15 μm in the Cu target, the particle defects formed on the Cu seed layer exhibit a pronounced linear increase as a function of the carbon particle number. However, such a linear relationship becomes unclear for the bigger carbon particles; meanwhile, a small quantity of bigger carbon particles in the Cu target also can generate more particle defects on the Cu seed layer in comparison with smaller carbon particles. Moreover, the formation mechanism of particle defects on the Cu seed layer was also discussed.
TLBO with variable weights applied to shop scheduling problems
Authors: Rodrigues Leonardo Ramos , Gomes João Paulo Pordeus
Published: June 2019

The teaching–learning‐based optimisation (TLBO) algorithm is a population‐based metaheuristic inspired on the teaching–learning process observed in a classroom. It has been successfully used in a wide range of applications. In this study, the authors present a variant version of TLBO. In the proposed version, different weights are assigned to students during the student phase, with higher weights being assigned to students with better solutions. Three different approaches to assign weights are investigated. Numerical experiments with benchmark instances of the flow‐shop and the job‐shop scheduling problems are carried out to investigate the performance of the proposed approaches. They compare the proposed approaches with the original TLBO algorithm and with two variants of TLBOs proposed in the literature in terms of solution quality, convergence speed and simulation time. The results obtained by the application of a Friedman statistical test showed that the proposed approaches outperformed the original version of TLBO in terms of convergence, with no significant losses in the average makespan. The additional simulation time required by the proposed approaches is small. The best performance was achieved with the approach of assigning a fixed weight to half the students with the best solutions and assigning zero to other students.
Effects of Compton scattering on the neutron star radius constraints in rotation-powered millisecond pulsars
Authors: Salmi Tuomo , Suleimanov Valery F. , Poutanen Juri
Published: June 2019

The aim of this work is to study the possible effects and biases on the radius constraints for rotation-powered millisecond pulsars when using Thomson approximation to describe electron scattering in the atmosphere models, instead of using exact formulation for Compton scattering. We compare the differences between the two models in the energy spectrum and angular distribution of the emitted radiation. We also analyse a self-generated, synthetic, phase-resolved energy spectrum, based on Compton atmosphere and the most X-ray luminous, rotation-powered millisecond pulsars observed by the Neutron star Interior Composition ExploreR (NICER). We derive constraints for the neutron star parameters using both the Compton and Thomson models. The results show that the method works by reproducing the correct parameters with the Compton model. However, biases are found in both the size and the temperature of the emitting hotspot, when using the Thomson model. The constraints on the radius are still not significantly changed, and therefore the Thomson model seems to be adequate if we are interested only in the radius measurements using NICER.
Therapeutic Plasma Exchange in Neonatal Septic Shock: A Retrospective Cohort Study
Authors: Sawyer Taylor , Billimoria Zeenia , Handley Sarah , Smith Kendra , Yalon Larissa , Brogan Thomas V. , DiGeronimo Robert
Published: June 2019

Objective This study aimed to examine the use of therapeutic plasma exchange (TPE) as adjunctive therapy in neonatal septic shock.

Study Design This retrospective cohort study was performed on a convenience sample of neonates in a quaternary children's hospital between January 2018 and February 2019.

Results We identified three neonates with septic shock who received TPE. Two neonates had adenovirus sepsis, and one had group B streptococcal sepsis. All neonates were on extracorporeal life support (ECLS) when TPE was started. The median duration of TPE was 6 days (interquartile range [IQR]: 3–15), with a median of four cycles (IQR: 3–5). Lactate levels decreased significantly after TPE (median before TPE: 5.4 mmol/L [IQR: 2.4–6.1] vs. median after TPE: 1.2 mmol/L [IQR: 1.0–5.8]; p < 0.001). Platelet levels did not change (median before TPE: 73,000/mm3 [IQR: 49,000–100,000] vs. median after TPE: 80,000/mm3 (IQR: 62,000–108,000); p = 0.2). Organ failure indices improved after TPE in two of the three neonates. Hypocalcemia was seen in all cases despite prophylactic calcium infusions. One neonate died, and two survived to ICU discharge.

Conclusion TPE can be safely performed in neonates with septic shock. TPE may have a role as an adjunctive therapy in neonates with septic shock requiring ECLS.
Workability and mechanical property of metakaolin phosphate acid based geopolymer
Authors: Dong Teng , Zhang Ying , Jiang Yixuan , Zhao Guodong , Yu Xingyu
Published: June 2019

Metakaolin and different molarity of H3PO4 were used to synthesis metakaolin phosphate acid based geopolymer (PAG) at 45°C and humidity more than 98%. The fluidity of fresh PAG decreases from 15.2 mm to 13.1 mm according to the increasing molarity of H3PO4. Initial setting time and final setting time of fresh PAG increases from 21 h to 62 h and 35 h to 87 h with the molarity of H3PO4 increase from 6 mol/L to 12 mol/L respectively. PAG is an early strength material, and the highest strength of PAG is 120.7 MPa at 28 day and strength at 7day is up to 90.8 MPa. Porosity decreases and pore size increases with the increasing molarity of H3PO4, Pore size between 50 nm and 100 nm is dominated in PAG. Some cracks was observed in hardened PAG.
Mix Optimization of Ultra High-rise Pumping Concrete Based on Efficacy Coefficient Method
Authors: Li Z G , Chen Heng
Published: June 2019

A new method is proposed to evaluate the combination property of ultra-high-rise pumping concrete for mix optimization. The weights of workability, strength and durability in regard to the concrete mix design are computed by the method of variation coefficient. Then, the aspects are unified into one dimensionless parameter named efficacy coefficient, and the performance of concrete is evaluated based on the value of the efficacy coefficient. The results of orthogonal experiments show that: the combination property of concrete can be evaluated successfully with the efficacy coefficient method. The results of optimization meet the requirements of engineering. This method is appropriate for mix optimization of ultra-high-rise pumping concrete.
Study on diffusion range and safe distance of natural gas venting
Authors: Lu Q M , Shu L
Published: June 2019

Due to the possible risk of flashover and explosion caused by the venting natural gas, in this paper, the PHAST software was used to determine the safe distance considering different factors. The results shows that the range of flashover is mainly depended on the venting pressure and venting, and once venting velocity within 20×104m3/h, the fire emptying is suggested. The range of flashover of natural gas in different directions were determined.
Requirements and guidelines for enterprise carbon emission management information disclosure
Authors: Zong Jianfang , Bao Wei , Sun Liang
Published: June 2019

As the significant bridge of communication between the enterprise and stakeholder, the enterprise carbon emission management information disclosure has gained more and more attentions. This paper introduces the purposes and basic principles of the enterprise carbon emission management information disclosure, investigates the domestic and overseas carbon emission management information disclosure conditions, illustrates the main contents contained in the enterprise carbon emission management information disclosure, and demonstrates the measurement methods of enterprise carbon emission management information disclosure. Finally, this paper discusses the advantages and disadvantages of establishing the enterprise carbon emission management information disclosure market in China, the significance of implementing the enterprise carbon emission management information disclosure, and prospects the future of enterprise carbon emission management information disclosure.
Study on Supercritical Carbon Dioxide Recompression Cycle System Employing Solar Energy
Authors: Huiyong Chen , Zhiheng Xue , Weifeng Wang , Tao Wu , Chang Fu
Published: June 2019

In this paper, a new kind of power generation system was built, which took solar energy as heat source of the system. All heat exchangers in the system adopted a new kind of heat exchanger type-Printed Circuit Heat Exchanger (PCHE). In order to take advantage of the abrupt property changes near the critical point of carbon dioxide, we selected recompression Brayton cycle. Then, given the operating conditions, the optimization progress was performed and the optimized parameters were obtained.
Thoughts on Carrying out Enterprise Energy Audit under the Background of New and Old Kinetic Energy Conversion
Authors: Guomin SONG
Published: June 2019

As China’s economy shifts from a high-speed growth stage to a high-quality development stage, it is an important measure taken by the country to promote supply-side structural reform to transform old kinetic energy and cultivate new kinetic energy, it is also the only way to promote economic restructuring and upgrading. In this context, this paper focuses on the new and old kinetic energy conversion strategy from the perspective of auditing, discusses the necessity of implementing energy auditing, explains the classification of energy audit, audit procedures, audit content and other issues, and hopes to help transform old and new kinetic energy from the perspective of auditing.
Preparation of biochar microspheres from leaves of several plants by hydrothermal method
Authors: Xia Yi-Chang , Hu Hao-Pan , Li Chun-Hao , Ren Hang , Shi Guimei , Xu Ge , Tian Bo , Shi Fa-Nian
Published: June 2019

In the paper, by means of orthogonal experiment, hydrothermal carbonization method, with the principle of preparation of carbon microspheres from glucose by hydrothermal method as reference and charring three different plants (ginkgo leaf, maple leaf and pine needle), we seek the possibility to carbonize plants into porous carbon with specific morphology and then to use the biochar for negative electrode of lithium ion battery. In process of the research, it was found that biochar microspheres (0.5um-5um) existed in several plant carbon obtained by hydrothermal carbonization, and some special elements (Mg, K, Ca, etc) were doped. Therefore, different materials were studied separately, the reaction temperature and reaction time were changed, and ultrasonic oscillation processing was used to find the best conditions for the preparation of biochar microspheres with specific doped elements, uniform particle size distribution and high yield.
Adaptability Planning of Transmission Grid with Integration of High-proportion Renewable Energy
Authors: Huaqiang Li , Ziyao Wang , Jinzhu Fan , Wanyu Liu
Published: June 2019

The large-scale integration of renewable energy to power grid is an important feature of future power system development, but renewable energy has strong fluctuation and high uncertainty, which will have a strong impact on power grid. In order to ensure the safe, efficient and reliable operation of power system, improve the acceptability of renewable energy in power grid planning, it is urgent to evaluate the adaptability of power grid structure to the strong fluctuation and uncertainty of renewable energy. Considering that the adaptability of power grid has a broad meaning and is difficult to quantify, this paper analyses the characteristics and actual operation state of the high-penetration renewable energy system and establishes an adaptability index series of power gird structure considering operation safety, efficiency and stability. Based on the adaptability indexes, a multi-objective transmission planning model is put forward. The improved chaotic crossover genetic algorithm and the nonlinear PCA method are used to solve the planning model. Finally, the simulation of Gaver-18 bus system demonstrates the feasibility and effectiveness of the adaptability indexes and planning model.
Suggestions for development of solar photovoltaic power generation projects in Guangdong Province
Authors: Han Miaomiao , Liu Xinxi
Published: June 2019

In this paper, the solar energy resources in Guangdong Province are divided into three categories according to the development and utilization value, and the development and evaluation of distributed photovoltaic projects and grid-connected photovoltaic projects are carried out for each region. According to the calculation results and sensitivity analysis, the development and evaluation suggestions for photovoltaic power generation projects in Guangdong Province are obtain.
Study on the Influence of Asphalt Content on Fatigue Life of Asphalt Mixture
Authors: Peng LIU , Jian WANG , Wei ZHUANG , Hao CHEN , Sai CHEN , Yu-feng BI
Published: June 2019

The fatigue failure form of asphalt pavement is not reflected in the design index of asphalt mixture proportion when determining the optimum asphalt content in the existing asphalt mixture proportion design. In order to solve the problem, the effect of different asphalt content on the fatigue life of three types of asphalt mixtures was studied by indirect tensile fatigue test.The results show that: (1) the splitting strength of asphalt mixture decreases with the increase of asphalt content; (2) the fatigue life of asphalt mixture increases first and then decreases with the increase of asphalt content; (3) the order of sensitivity of fatigue life of three types of asphalt mixture to asphalt content is: AC-5 > STRATA > ATB-25.Some useful suggestions are put forward for the design of asphalt mixture with good fatigue resistance.
Numerical Study on Oblique Hysteresis Performance of Composite-sectioned Square Concrete-filled Stainless Steel Tubular Columns
Authors: Zheng YuTing , Zheng LianQiong
Published: June 2019

The composite-sectioned square concrete-filled stainless steel tubular column has the characteristics of high rigidity, strong integrity, reasonable force, beautiful structure and low maintenance cost. It has good performance in marine platform and cross-sea bridge structure and urban landmark buildings with high corrosion resistance. However, there are few studies on the performance and design methods of this kind of structure, which restricts its application. In this paper, Finite-element models (FEMs) for analyzing the tangential hysteresis behavior of the composite-sectioned square concrete-filled stainless steel tubular columns were established and verified. A parametric study was conducted on the influence of axial compression ratio, internal and external tube diameter ratio, and oblique angle. The calculated results showed that, the composite-sectioned square concrete-filled stainless steel tubular column has good oblique hysteresis ability, but the larger axial pressure ratio or larger oblique angle will weaken the capacity, while the pipe diameter has little effect on it.
Finite Element Analysis of the Joint Surface of Concrete Filled Steel Tubular Frame Column and Precast Shear Wall
Authors: Yang Shaokun , Zheng Lianqiong
Published: June 2019

In order to study the connection performance of a new type of shear key to concrete filled steel tubular (CFST) frame column and precast shear wall, a numerical model is established by using the finite element software Abaqus, the mechanical properties of the combined shear wall are studied by the strength of post-poured concrete, the yield strength of the shear key steel and the spacing between the shearing bonds. The results show that the failure modes of specimens are mainly related to the strength of post-poured concrete and the yield strength of shear keys. When the specimens are damaged by shear bonds, the bearing capacity and ductility of the specimens increase obviously with the increase of the yield strength of the shear key steel and the shortening of the spacing between the shear keys. The change of strength of post-poured concrete has little effect on the working performance of specimens. When the specimens are damaged by post-poured concrete, the stiffness of the specimens is larger and the ductility is worse.
Discussions about Water Resources Allocation
Authors: WEN Qing , ZHANG Liudong , Fei Xingxing , LI Jingdong
Published: June 2019

Based on the reasons of water resources allocation, the current domestic water resources distribution profile is analyzed, which can provide a theoretical basis for the future development of water resources allocation in various regions. Water resources allocation is one of the effective means to solve the uneven distribution of water resources in China. This paper reviews its development process, summarizes the development process of water resources allocation model, and forecasts the future development trend of water resources allocation research.
Determination of Tiopronin using Potassium Bichromate Discoloring Spectrophotometry
Authors: Wen Xinrong , Tu Changqing
Published: June 2019

A new method for the determination of tiopronin by potassium dichromate discoloring spectrophotometry is established. The optimal conditions for the discoloring spectrophotometric determination of tiopronin by potassium bichromate are discussed. In the sulfuric acid medium, potassium bichromate can oxidize tiopronin, and its absorbance decreases with the increase of tiopronin concentration. The decrease value of absorbance is linearly related to the concentration of tiopronin, and the content of tiopronin can be indirectly determinated by measuring the decrease value of absorbance. Within the scope of 0.02000-0.2000 mg/mL, the equation of linear regression is ΔA=-0.005+1.96C (mg/mL), and linear correlation coefficient is 0.9991. This method is used to the determination of tiopronin in tiopronin tablets, and the results consistent with standard method.
Geostatistical estimation analysis of typical Carlin gold deposit in Hunan province, China
Authors: Huang S , Xie Y L
Published: June 2019

In this paper, 3D mining modelling software was used to construct the 3D geological model of Typical Carlin gold deposit in Hunan province of China, and the geostatistics theories are also involved for the resource estimation which offer references for additional exploration and mining plans. Access database was constructed for gold deposit, topo DTM, mineralised body models and grade models are constructed by Surpac, and also analysis of the spatial grade distribution in reality was completed with statistic softwares. By using of geostatistics, assay samples are composited and analysed statistically and outliers influence was reduced to certail level. Experimental Variation functions were constructed for the strike, dip and vertical directions. Certain attributes are estimated by Ordinary Kriging estimation method. Comparing to the traditional estimation methods, estimation under 3D block model can obtain more reliable analysis results, which have significant reference values for dynamic management of mine operation.
FeCo1.6Mn0.4O4 microspheres as catalysts for oxygen reduction reaction
Authors: Wang Bowen , Zhang Ru , Lei Ming
Published: June 2019

The representative spinel-type materials AB2O4 (Both of A and B are transition metals) electrocatalysts for oxygen reduction reaction (ORR) have been investigated widely. But FeCo2O4 was not explored widely as the ORR electrocatalyst. The element of B site in AB2O4 had a determined influence on the electrochemical performance of the sample according to the previous research. In this work, a part of Co element at B site in FeCo2O4 was doped by Mn to improve the electrochemical performance for the popular research. FeCo1.6Mn0.4O4 microspheres were prepared and characterized with XRD, SEM, XPS. The electrochemical performances were tested and the results were analyzed. Meanwhile, the stability and methanol tolerance ability of catalysts were also measured. The work found a superior performance and non-precious catalyst for oxygen reduction reaction.
Thermosensitive N-isopropylacrylamide Nanoparticles Hydrogel Application on Biomolecules Identification
Authors: Zhang Herong , Kang Linlin , Xue Min
Published: June 2019

Intelligent hydrogel is hydrophilic polymer gel which is immiscible but significantly swells in water. Thermosensitive nanoparticles hydrogel is a kind of intelligent hydrogels, and its volume phase could change with the external temperature value resulting to its typical of low critical solution temperature. It has extraordinary nanometer characterization and sensitivity to the stimulus of the environmental conditions. In recent years, thermosensitive N-isopropylacrylamide nanoparticles hydrogel are one of the hotspots in hydrogels research. They have attracted much attention in the field of biomedicine due to their good biocompatibility and sensitive temperature response. Thermosensitive N-isopropylacrylamide nanoparticles hydrogel show good application prospects in drug delivery system, protein separation, medical diagnosis, biosensors, biomaterials and other fields. In this paper, the application research and development prospect of N-isopropylacrylamide thermosensitive nanoparticles hydrogel in macromolecule recognition was mainly summarized from protein to peptide. Moreover, the employ of nanoparticles in drug delivery and release, and capillary electrophoresis for DNA separation were also overviewed. Further promising applications of this biological material in macromolecule recognition are ever-accelerated. It is expected that thermosensitive N-isopropylacrylamide nanoparticles hydrogel will break through the limitations of biomedical field and be widely used in other fields.
Recent advances in hydrogen storage of MgH2 doped by Ni
Authors: Liu Huan , Wang Zhenzhong , Zhang Jianzhong , Tao Bin , Liu Quanzhen
Published: June 2019

Efficient hydrogen storage remains a tough challenge for the past decades, and MgH2/Mg systems seems as a most promising solution due to its high hydrogen capacity, low cost and universal abundance. However, high sorption temperatures, sluggish kinetics of hydrogen desorption, and poor cycle performances of the MgH2/Mg systems hinder further applications. In this review, both experimental and theoretical researches of Ni doping MgH2 materials are presented aiming at improving the hydrogen desorption/absorption performances, and some realistic perspectives are also provided for further investigations.
The Oil and Gas Industry and the Development of the Natural Gas Automobile Industry
Authors: Zhang Hao , Yin Dandan
Published: June 2019

Since the 21st century, the natural gas industry has matured gradually with the accelerating consumption of oil resource, so that the traditional gas-guzzling automobile industry developed a new direction for the new fuel-efficient car industry. The proportion of natural gas import continues to increase with the continuous downturn of oil price. This is not a lack of domestic gas supply capacity, but follows market and current policy trends to encourage gas imports. For decades, Europe and Japan have invested a lot of money and manpower used in automobile alternative clean fuels, research, development and test of new car, and accumulated rich experience in technology and popularization. Although it started late in China, it is close to or above the international level in some technical fields, such as electric cars.
Preparation of mullite fine powder and its characterization were prepared by sol-gel method
Authors: ZHANG Li , HAN Guo-cai
Published: June 2019

High purity mullite powder was prepared by sol-gel method. Mullite was prepared with Ethyl orthosilicate, nitric acid aluminum, hydrochloric acid, anhydrous alcohol and distilled water as raw material by sol-gel method. After drying, calcining and grinding, the precursor gel is prepared with mullite power. This paper tries to adopt the control variable method and the properties of mullite powder are studied under different pH values and other experiment conditions. All the studies showed that when the PH value was 2-3, the prepared mullite micropowder generally had smaller particle size and higher purity.
Simulation of Climbing Process of Aircraft on Plateau Airport
Authors: CHEN D F , ZHU Z Q , CAI L C , PANG K , XUE J
Published: June 2019

In order to solve the problem of the minimum climbing gradient of plateau airport and the problem of limiting slope at ends of clearance obstacles, we establish a model for calculating the performance of aircraft climbing and analyse the performance of climbing during the flight of the aircraft in the course of taking off. Through the simulation calculation, the variation law of the flight route height at different air pressure heights is analysed for the aircraft’s full and one engine failure, and the relationship between the flight path gradient and the air pressure height when the aircraft is in full engine and one engine failure condition is established.
Prediction of penetration depth of earth penetrator based on neural network
Authors: Zhuo Chen , Huixiang Sun , Yingwu Wang , Huan Niu
Published: June 2019

An artificial intelligence neural network model is established in this essay to seek a more general method for predicting penetration depth of earth penetrator, to comprehensively analyze the effect of various parameters on penetration depth as well as to predict the penetration depth of earth penetrator.This paper, by means of numerical simulation, and determined the ordnance penetrator warhead curvature radius, the length of the projectile, the density of the projectile,the density of the target protective layer, the elastic modulus of the target protective layer and the hit velocity of the earth penetrator.This six key parameters as the input data of neural network model, and by using numerical simulation to obtain the data needed for training the neural network model samples. According to the characteristics of six input data and one output data of the neural network model, the possible structure of the neural network model is set, and the optimal model structure is selected through training. We built neural network model to forecast the ordnance penetrator penetration depth, analyzes the six key parameter’s influence on the depth of penetration, the results show that reducing the warhead curvature radius, increasing the length and density of the projectile, properly increasing the impact velocity of the projectile can improve the penetration ability of the earth penetrating projectile, and increasing the density and elastic modulus of the target protective layer can improve the anti-penetration ability of the protective layer.
Numerical Study on Transport of High Concentration Suspended Sediment Water in Artificial Seawater Lake
Authors: Huamin ZHOU , Shichang HUANG , Xin ZHAO , Yongqiang NI , Dan XU
Published: June 2019

The sea water near the estuary of Yangtze River is high in sediment concentration and low in transparency. Clear coastal water can be found in artificial sea lakes, which are isolated from outer sea water by reclamation projects in the intertidal zone. But the water supplied by sea for the artificial lake exchanging is still a big problem. Transport of high concentration suspended sediment (SS) water in artificial seawater lake is studied. The water supplied from the small lake (sand basin) cannot meet the requirements of the landscape and recreation needs of the big lake, as the SS concentration is 0.2 kg/m3. After adding the ecological barrier in sand basin, the SS concentration of most water area in big lake is below 0.1 kg/m3. This idea can be used as reference for water quality control of seawater artificial lake.
Study of aramid and carbon fibers on the tensile properties of early strength cement mortar
Authors: Nie Liangxue , Xu Jinyu , Luo Xin , Chen Haowen , Chang Sen , Wang Tengjiao , Liu Gaojie
Published: June 2019

The sulfoaluminate cement was used to prepare the high early strength cement mortar specimens (HESCM) with 0.1%, 0.2% and 0.3% volume content of aramid and carbon fibers, and the contrastive studies of the specimens on compressive and tensile properties were presented in this paper by using of universal testing machine and electronic precision servo tensile test machine. The tests reveal that the addition of aramid and carbon fibers has a positive effect on compressive strength, tensile strength, tensile strain and tensile toughness of specimen, and the bigger the volume content of fiber, the more significant on improvement. What’s further, the tensile toughness has the maximum improvement, while the compressive strength increases minimum, and aramid fiber produces a better improving effect on these properties than that of carbon fiber.
Study on performance of fly ash slag cement grouting materials
Authors: Cui Jingyu , Zhang Wuyu , Ji Xi , Ji Gang-ao
Published: June 2019

In view of the high cost of the existing grouting materials, and at the same time the industrial production of a large number of fly ash, slag and other industrial waste can’t be effectively used. In this paper, the properties of fly ash slag cement with different ratios were studied through laboratory tests. Results show that the cement content in given conditions, with the increase of dosage of fly ash, initial setting and final setting time of cement paste with slow growth, the fluidity is growing, but the stone rate has obvious drop, on the compressive strength, the higher the slag content, is the early compressive strength, the greater the and the higher the dosage of fly ash, the late strength of cement paste were higher. This kind of grouting material has good working performance, can guarantee the project construction needs at the same time save cost, protect the environment.
Study on carbonation technology of alkaline uranium mother liquor
Authors: Xing FAN , Shao-hui KANG , Da-bing LI , Yan SONG , Kang LIU
Published: June 2019

The characteristics of the main components of alkaline uranium mother liquor: A small amount of uranium, a certain amount of hydroxide, and a large amount of carbonate. Through the analysis of chemical reaction and diffusion about transfer between mother liquor and CO2, the influencing factors of mother liquor carbonation were determined: Gas-liquid transfer, reactant concentration, reaction temperature, etc. Tower counter-current was selected to investigate the influence of different types of fillers on carbonation effect. The stainless steel triangular spiral filler was optimized. The filling tower device for carbonation of uranium mother liquor was finalized, which greatly improved the gas-liquid distribution efficiency and carbon dioxide absorption rate. The effect of residual alkali concentration and reaction temperature of mother liquor on carbonation effect was investigated. The technology realizes the conversion of sodium hydroxide to sodium carbonate in the mother liquor. When sodium carbonate is converted to sodium bicarbonate, it can be converted to the saturated concentration of sodium bicarbonate, and CO2 is absorbed in both stages. The device can be used to control the degree of carbonation of the mother liquor according to the demand, and be returned as leaching agent or eluent, realized the full reuse of the remaining alkali in the mother liquor.
Qualitative and quantitative evaluation of small and medium-sized rivers based on data resources
Authors: Fu Lei , Wang Junmin , You Aiju , Yu Jia , Yang Yi
Published: June 2019

Over the past three centuries, due to the improvement of the understanding of the natural environment and social service function of rivers, many countries in the world have started the research and practice of river health evaluation. However, the connotation and definition of river health has not formed a unified standard around the world. Recently, there are many studies on the ecological health of large rivers in China, and a relatively acceptable hydrological and water quality monitoring system has been established for those large rivers. However, the health evaluation of various small and medium-sized rivers is still in the preliminary stage. Though many commonly used evaluation methods have been introduced in China, it is still difficult to carry out health evaluation in small and medium-sized River areas due to the lack of basic data, the difficulty of real-time monitoring, the complexity of index calculation formula and other factors. Based on the current situation of construction, management and monitoring of small and medium-sized rivers in China, this study uses qualitative and quantitative methods to evaluate the health of typical small and medium-sized rivers, and compares the evaluation systems and results of the two methods in order to find a suitable river health evaluation method for typical small and medium-sized rivers in China under limited data resources.
Comparative Analysis on Energy Storage Policies at Home and Abroad and Its Enlightenment
Authors: Xiao Yanwei , Gao Yijing , Kuang Sheng , Sun Ke , Yang Liqiang , Hu Jiansheng , Wang Beibei
Published: June 2019

In this paper, current development of energy storage(ES) in China and the United States is introduced firstly. Then, the typical ES policies of China and the United States are enumerated from the perspectives of general policies and multi-angle policies, which is consists of the generation side, the grid side and the user side. Through the analysis of the policies, the paper expounds the promoting effect of various ES policies on its development and makes a comparison of ES policies in China and the United States. Finally, according to the policies mentioned in this paper, combined with the current national conditions in China, the enlightenment and suggestions on policy formulation of ES are given due to the current national conditions in China.
Brief Analysis on Industrial Restructuring and Diversified Development of Mineral Economy
Authors: Yun DING
Published: June 2019

Under the background that the global mining situation continues to be sluggish and Chinese economy has entered a new normal era, numerous problems are appearing, such as mining exploration financing difficulties, information asymmetry and imperfect market-based management. The combination of “Internet Plus” and “Mass Entrepreneurship and Innovative” with the traditional mining and large enterprises is an effective way of promoting mineral economic transformation and upgrading.