bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-layer Authentication in Keystroke Dynamics using Time based Tool
Authors: Bhasin Namisha , Tarar Sandhya
Published: January 2021

Having a secure and sound system is the most important need of the end-user. Confidential and authentic information about the system must be available to the genuine user when required. This paper presents a generalized Keystroke Dynamics Technique for identification of genuine users. The method works for the authentication of the user while user is entering the password to using the system. It is a three-layer approach which first check the typing pattern while entering the password then it also monitors the system while user is using the system. Different users have different typing pattern which could be used to recognize a user. For identification of the user a time-based tool is used to collect data pertaining to the typing time of each user for words of different lengths. This is a very easy and cost-effective way of collecting data for differentiating between a genuine user and imposter. At first layer elbow method is used to know unknown targets depending upon different word combinations. For the second layer principal component analysis (PCA) is used to find suitable factors where user typing pattern is making users indistinguishable. For the third step Long-Short Term Memory (LSTM) technique is used to forecast whether the user is a genuine user or an imposter.
Solution of Einstein’s Field Equations for the Static Fluid Sphere
Authors: Singh Abhishek Kumar
Published: January 2021

In this paper we deals about some exact static spherical solution of Einstein’s field equations with Λ = 0 (cosmological constant) and p = ρ (taking suitable choice of g11 and g44). We have eψ = km5 4 and e−χ = l, which help to investigate the value of eχ. Here some previously known solutions are contained as a particular case. The explicit expressions for rotation, shear scalar of expansion and fluid velocity have also investigated. We get some previously known solution for distinct values of n. Here Λ = 0, this implies that Einstein element would degenerate into a line element of special relativity for flat space time. It also helpful to investigates solution for the perfect fluid core.
Evaluating Artificial Intelligence in Education for Next Generation
Authors: Joshi Shubham , Rambola Radha Krishna , Churi Prathamesh
Published: January 2021

The use of Artificial Intelligence (AI) is now observed in almost all areas of our lives. Artificial intelligence is a thriving technology to transform all aspects of our social interaction. In education, AI will now develop new teaching and learning solutions that will be tested in different situations. Educational goals can be better achieved and managed by new educational technologies. First, this paper analyses how AI can use to improve outcomes in teaching, providing examples of how technology AI can help educators use data to enhance fairness and rank of education in developing countries. This study aims to examine teacher’s and student’s perceptions of the use and effectiveness of AI in education. Its curse and perceived as a good education system and human knowledge. The optimistic use of AI in class is strongly recommended by teachers and students. But every teacher is more adapted to new technological changes than students. Further research on generational and geographical diversity on perceptions of teachers and students can contribute to the more effective implementation of AI in Education (AIED).
Students’ perceptions towards IoTs adoption: A case study
Authors: Singh Upasana G , Msibi Andile
Published: January 2021

The Internet of Things (IoT) is expanding the interdependence of people, objects and systems. It has enforced the idea of a global infrastructure of “things” networked to enable unlimited connectivity, communication and collaboration across physical, biological and digital spheres. The ever-present internet is the foundation of this phenomenon (IoT) and continues to facilitate innovation in this field. Over the past decade, many forms of IoT have been widely adopted in manufacturing and enterprise spaces, which has led to dramatic changes in production processes and the supply chain. Despite the convenience, real-time monitoring and reporting capabilities offered by IoT adoption amongst individual consumers is unclear. The purpose of this paper is to understand the factors that determine the adoption of IoT devices and/or applications by individuals whether for education, job, security or health purposes. The study uses mixed methods research to examine the factors of IoT adoption by individuals in their daily lives. Qualitative and Quantitative analysis using the Technology Acceptance Model (TAM) reveals how perceptions of users affect the intention to use Information Technology (IT) and actual adoption. One hundred students from the University of KwaZulu-Natal (UKZN) participated in the study. The findings of the study revealed that positive attitude towards usefulness, ease of use, user satisfaction had a positive influence on the adoption of IoT devices and/or applications. It also revealed that affordability, basic knowledge, tech savvy attitude, security and internet access influence the behaviour of users and non-users of IoT technologies.
Assessing Impact of Climate Change on Rainfall Patterns of Vadodara District, Gujarat, India
Authors: Shah N V , Patel Y S , DBhangaonkar P
Published: January 2021

Due to climate change, variable rainfall pattern and rapid urbanization during last two decades, Vadodara district is frequently facing problems related to flooding. In present research paper frequency Analysis is carried from the available hydrometeorologicalhistorical rainfall data series of past four decades for Vadodara District, Gujarat. Rainbow software is used to carry out the analysis. Homogeneity of data is checked and Goodness-of-fit is tested. A logarithm transformation is selected to plot magnitude of event and corresponding probabilities of exceedance. The mixed Global probability distribution is used to explore the re-occurrence of rainfall events with certain return period. Analysis revealed that the rainfall events causing extreme flooding conditions in Vadodara District has frequency of re-occurrence as 25 years.
Study of Echo Cancellation approach by using Least Mean Square (LMS) Algorithm
Authors: PavanKalyan I. , Jaya Santosh G. , Prasad K.H.K. , Nandan Durgesh
Published: January 2021

Sound is the origin of communication. We are using sound channel for interaction. The acoustic signal introduces echo signal properties which lead the original signal as error signal. In most of applications the adaptive filters implemented in time domain works quite efficiently. However, the complication of the adaptive filter increases as the impulsive reaction becomes quite large hence it cannot be implemented efficiently in time domain. Acoustic echo cancellation is one example where this can happen. In this paper we will explain about to acoustic cancellation and different methods that are adopted to overcome the interference of noise by using various levels of algorithms and apply it to an error signal and makes solution for the problem, verifies the performance, describe the best and suitable technique which gives most effective results.
Research on EFI multi-point synchronous initiation technology based on mems process
Authors: Su Q , Chu E Y , Xie R Zh , Liu W , Han K H
Published: January 2021

In order to solve the problems of the warhead initiation system due to the low safety of conventional detonator arrays and the poor synchronization of the explosion logic network, as well as the MEMS batch integration requirements, a research on EFI multi-point synchronous initiation technology based on MEMS technology was carried out. Explosive foil was prepared by magnetron sputtering and photolithography. SU-8 photoresist flying sheet layer and acceleration chamber were prepared on the bridge foil by UV thick glue technology, and single-point, two-point parallel and three-point parallel were realized. The two batches of two and a total of four points and three strings of three and a total of nine points explosion foil initiators were batch-integrated and tested for the synchronism of the flying sheet effect. The test results show that the average time between two points, three points, and four points is less than 80ns, and the synchronization time is small; the average time at nine points is less than 200ns, and the synchronization time is large.
Study on the explosion field temperature and gas products of FOX-7 / RDX based aluminized explosives
Authors: Yang X , Tian X , Zhao K , Dong J , Huang Y F , Feng B , Wang X F
Published: January 2021

To investigate the effect of RDX on the explosion reaction mechanism of FOX-7 based aluminized explosives in vacuum environment, the explosion field temperature of FOX-7 based aluminized explosives and RDX/FOX-7 based aluminized explosives were measured in an isolated explosion chamber. The results show that adding RDX would increase the equilibrium temperature of explosion field of FOX-7-based aluminized explosives. The equilibrium temperature of FOX-7-based aluminized explosives and RDX/FOX-7-based aluminized explosives increases first and then decreases with the increasing of Al content, which shows the highest equilibrium temperature as the Al content is 30%. When the Al content is less than 25%, the explosion peak temperature of FOX-7-based aluminized explosives would increased by adding RDX, and when the aluminium content is more than 30%, the explosion peak temperature of FOX-7-based aluminized explosives can be reduced by adding RDX.
A preliminary study in to the viability of sponges as a proxy for sus scrofa (domesticus) lungs for ballistic evaluations
Authors: Pullen A E , Kieser D C , Hooper G , Plummer T C H
Published: January 2021

While tissue simulants are considered best practice for ballistic evaluations, there is an ongoing debate about the use of tissue simulant and their relevance and there are calls to improve models by making them more anatomically relevant by the introduction of bony structures and organs. Therefore; the aim of this study was to try and determine if sponges and/or ballistic gelatin may be a suitable proxy to porcine lungs using 5.56x45mm (MK262-MOD1). Four sample groups consisting of 10% ballistic gelatin blocks, lungs embedded in gelatin, kitchen sponges and car sponge in gelatin were evaluated. Analysis included determining the onset of yaw, time from impact to the onset of yaw, temporary and permanent cavity characteristics and energy deposition. The results indicated that the kitchen sponge and car sponge may be a suitable proxy to porcine lungs, however there were significant differences between the lung model and plain gelatin blocks and additional work should be carried out to investigate the suitability of sponges as a proxy to porcine lungs further.
Research on mechanical properties of different coating structures reactive fragments
Authors: Chen Peng , Yuan Bao-Hui , Qu Ke-Peng , Quan Jia-Lin
Published: January 2021

In order to study the dynamic compressive properties of reactive material which coating different shell thicknesses at various strain rates, Split Hopkinson Bar (SHPB) has bee used. The stress-strain curves at different strain rates were obtained under uniaxial stress loading condition. The results show that reactive materials and reactive fragments of coated structure have obvious strain rate effect. The yield strength of the 20# steel coating is 10 times higher than internal reactive material. The mechanical properties of coated reactive fragments are greatly affected by the thickness of the coating. The yield strength of the reactive fragments of the shell thickness of 1mm and 2mm cladding is 300MPa and 520MPa, respectively.
Design and locomotion analysis of a novel cube mechanism with probabilistic rolling
Authors: Guan Y H , Yao Y A , Liu C
Published: January 2021

This paper proposes a novel cube mechanism that is capable of probabilistic rolling locomotion. The mechanism composes of 8 vertex modules and 12 links. A kinematic model is presented, then the deformation and locomotion characters of the mechanism are demonstrated by kinematics analysis. So, we know that there are two probable orientations in the rolling locomotion. This stochastic process accords with Bernoulli experiment in ideal condition. The stability and the tumbling condition are discussed by the rolling locomotion analysis. The dynamics model is built and the locomotion simulation is done. The results show that the rolling locomotion can be realized with alternate two types of gaits which are advancing gait and turning gait. In both of advancing gait and turning gait, the orientations are probabilistic. A prototype is manufactured, the advancing and turning function is verified through the tests.
Force-free control of low drag resistance for humanoid robot joint
Authors: Yu Han , Huang Gao , Liu Yaliang , Meng Libo , Chen Xuechao , Yu Zhangguo
Published: January 2021

A method for the force-free control of humanoid robot joints is presented that meets human–machine cooperation functions of a humanoid robot. To ensure accurate torque control, the current loop of the permanent magnet synchronous motor was initially optimised and its dynamic response improved with a compensating back electromotive force. The motor speed is then estimated by sampling the voltage and current, the values of which are used in the calculation of the joint angle and the gravitational-force compensation. Finally, a method to evaluate the dynamic force compensation is applied that then yields the motor output offset, the total gravitational load, the partial inertia force, and the partial friction moment. Experimental results show that this method reduces the drag torque to less than 1 Nm. This method can be widely applied to a variety of robotic joints.
Indonesia’s cyber diplomacy strategy as a deterrence means to face the threat in the indo-pacific region
Authors: Fathan Taufik A
Published: January 2021

This paper discusses Indonesia’s cyber diplomacy strategy as a deterrence means to deal with the threat of cyberspace security in the Indo-Pacific region. Advances in information and communication technology in each country have driven new threats in cyberspace. Indonesia as one of the highest internet user countries in the world is inseparable from the threat of attacks in the cyberspace. The literature method is used to interpret the problem and to present more details in the cyber diplomacy efforts. This literature method approach is used to find perceptions and definitions from various references in relevant contexts and to carry out a process of identifying the defense forces possessed by cyber institutions in Indonesia and the challenges faced in the Indo-Pacific region. Following the circumstances, risk mitigation can be carried out as the basis for developing cyber diplomacy strategies and policies in Indonesia. However, this defense diplomacy strategy may not be effective if it is only carried out in dichotomic by one or two agencies only.
Design of individual soldier situation generation software based on AR
Authors: Ma W X , Pei K K , Zhang M , Fan X D
Published: January 2021

According to the requirements of the individual combat command system for real-time emergency command and battlefield situation, the software design based on the AREngine platform for the individual battlefield collaborative situation generation is studied. Using the domestic smart phone to carry out the augmented reality situation of the traditional sandbox, and make full use of the powerful AR function of the smart phone with the core processing equipment of the individual soldier system equipped by the infantry commander and the combat personnel, providing the infantry with infantry command, combat deduction, The realistic deployment of power deployment and battlefield situation can be used for wartime preparation of troops and strategic deployment during simulation training, which has practical significance.
An efficient enhanced automatic target recognition approach
Authors: Bahy Ramy M
Published: January 2021

This paper presents a new efficient enhanced automatic target recognition approach based on hybrid feature and intensity based methods. The proposed approach is based on comparison and matching between the acquired target image and the stored database images through edge detection, morphological operation, image transformation, image histogram matching and mutual information for both target and stored database images. Sobel operator is used to detect edges in both acquired target image and the stored database images. Hough transform is used as an image transformation which groups the extracted edge points in edged images to an appropriate set of lines which helps in features extraction and matching processes in both of target and stored database images. This gives an initial indication about realization and recognition between target image and its corresponding database image. Comparisons of image histogram and mutual information for both target and database images are finally used to emphasize the recognition of the target image and its verification with its corresponding database image. The proposed recognition approach passed through four stages which are: edge detection by Sobel edge detector, thinning as a morphological operation, Hough transformation, matching process using median deviation and finally histogram matching and measuring the mutual information between target and the available database images. The experimental results proved that the proposed hybrid target recognition approach gives a more accurate and successful recognition rate than other techniques which depend on using feature based methods or intensity based methods.
Autofocus microscope system based on blur measurement approach
Authors: Bahy Ramy M
Published: January 2021

Blurred (out-of-focus) images hinder the process of accurate cell counting in medical images. Cell counting is considered an important method to quantify cells for disease diagnosis and medical research. The hemocytometer is used to count cells as it is a cheaper and simple method. The specimen which contains cells is loaded into the hemocytometer and placed on a microscope. In this paper, a new autofocus technique is proposed to automatically adjust the microscope knobs by controlling the movement of adjusting knobs. This method is based on measuring and evaluation of the amount of blur annoyance in cell images. Whereas, adjusting knobs of microscope is a time consuming especially for beginners. Also, the automatic adjustment avoids losing the knob gear if it is used for several times or used in a wrong way. A CCD camera is attached to the microscope to capture images of specimen under test. An efficient blur metric is used to evaluate the amount of blur in captured images. The microscope knob is attached to a stepper motor to control its movement. The movement is stopped when the well-focused image is obtained. The proposed method has proved that it is an efficient method to automatically adjust the microscope knobs and get a well-focused image. The proposed method is compared with another recent approach that is based on an evaluation of a contrast measurement in images to automatically control the microscope knobs. The results proved that the output in-focus images by using the proposed approach for auto-focusing the microscope system have low blur values and much closer to the quality of the original reference images. Moreover, the proposed method which is based on blur measurement gives a higher image quality than one of the most recent approaches that depends on contrast measurement.
Improvement of flow condition in channelized river due to stacked boulders
Authors: Yasuda Y
Published: January 2021

Recently, a channelized river was constructed in natural rivers from the point of flood control, and the river fell into drainage channel. During flood stages, it might be impossible for aquatic animals to stay at channelized river. Also, degradation and disappearance of gravel bed might be formed easily, because flood flow was concentrated into the same route for normal stage. The improvement of flow condition in channelized river must be required as soon as possible. As a short-terms of construction for the improvement, the installation of stacked boulders might be helpful for both habitat and refuge of aquatic animals. The installation of stacked boulders with about 1 m size was conducted at channelized portion with 20 m wide and 1/200 slope in Kando River, Shimane Prefecture, and a surface jet flow with three dimensional could be formed in both normal and flood stages. After the installation, several kinds of aquatic animals could be observed around stacked boulders, and movable gravels with 3 mm to 100 mm diameters were deposited below stacked boulders. The stability of stacked boulders during flood stages was investigated experimentally by using 1/15 scale model. Further, the possibility of refuge space in stacked boulders was investigated in proto scale by using 25 eels.
The price of resource consumption using the Ecopoint concept under consideration of regional differences
Authors: Grause G
Published: January 2021

The Ecopoint concept was developed to control the worldwide resource consumption. Resource shares are distributed to the world’s population and freely traded among individuals. The number of shares limit the amount of resources that can be used. In this work, the question is investigated how plastic production is affected by such a system under special consideration of local difference in the energy generation and way of goods transportation. The polymerization of high-density polyethylene (HDPE) was modelled using a combination of the databases Ecoinvent 3.4 and Exiobase 2.2 for different feedstocks: fossil fuel in Brazil, the USA, and Germany; sugar cane in Brazil and India; maize in the USA; and grass in Switzerland. As a result, regional conditions have a strong impact on the resource consumption and the Ecopoint price. Using mainly fossil fuels for energy production increases the Ecopoint price by 30%. The combination of renewable energy and biomass as feedstock can significantly reduce the resource consumption. The resource consumption of the combination of fossil fuel for energy production and biomass as feedstock for HDPE is comparable to the use of renewable energy and fossil fuel as a feedstock. An Ecopoint price of 0.07 to 0.12 US$ would make HDPE from biomass competitive to such from fossil fuel.
Calculation of surrounding rock pressure of large section underground excavation metro station based on the construction process
Authors: Zhang Y T , Jin X G , Dai Y J , Li H L , Yang W G
Published: January 2021

The traditional calculation method of the surrounding strata pressure of the tunnel does not consider the tunnel construction process. The excavation of the large-section tunnel mostly adopts the section excavation method, which is to excavate and support at the same time. The stress state of the pressure of surrounding strata changes gradually during the excavation process. The traditional calculation results of tunnel surrounding strata pressure are generally large. In this paper, the large-section tunnel is simplified into three parts, and the degree of influence (η1, η2, η3) of the excavation height h and width b of the advance pilot hole and the distance d between the advance and rear pilot tunnels on the surrounding rock pressure calculation are analyzed. The regression equation for calculating the influencing factors (tunnel depth H, tunnel span B, internal friction angle ϕ, and rock weight γ) of surrounding rock pressure (p) is established. Through the numerical analysis, the influence coefficient η is obtained, the weight coefficient is introduced, and the computing formula of the pressure of surrounding strata of the large-section tunnel excavation is derived. The formula is used to the computing of the pressure of surrounding strata with a large-section subway station and the correct conclusion is obtained.
Scheme comparison and key construction technology for swivel rider cap of some super major bridge
Authors: Zhang D S
Published: January 2021

In order to solve the technical problem of spherical coupling construction for bottom swivel, improve the construction quality of bearing platform and accumulate the experience of spherical coupling construction, the construction scheme and key technology were studied by taking the construction of rotary rider cap across existing Changshen Highway in the new Tongliao-Xinmin north passenger dedicated line as an example. “Two-step method” construction process of spherical coupling and the sealing method of fast and effective were proposed, and the spherical coupling compactness and construction quality were guaranteed. The results of engineering practice show that spherical coupling construction scheme about “C60 self-compacting concrete +spherical coupling ‘two-step’ construction + grouting filling” is feasible, and the application effect is good.
Influencing factors of the drying rate of sludge for solar drying chamber
Authors: Li J , Yan J G , Wang Y F , Yang K , Shao Y Y , Shao Y Q , Wang Q C , Zhu Y
Published: January 2021

In view of the problems of low solar energy utilization efficiency, drying efficiency to be improved and sludge adhesion in the process of solar drying sludge, the research was carried out on the heat collection effect of solar collectors, sludge drying characteristics and sludge drying process, as well as the influence of sludge drying process parameters on the sludge drying rate such as hot air temperature, solar radiation intensity and air substitution,. on the self-built industrial simulation test bench. The results show that: the maximum temperature difference between the inside and the outdoor environment of the solar collectors is 36°C, when the outdoor environment temperature of the developed solar collectors is 13-26°C; the optimum process parameters of sludge drying rate under the experimental conditions that the moisture content of wet sludge is 82.7%, are as follows: the temperature of hot air is 43°C, the maximum solar radiation intensity (about 12:00), the optimal flow rate of air is controlled at 1.2m/s, the thickness of the material layer is 3cm, the large contact between air and materials improves the problem of sludge adhesion. All which provide a theoretical basis for the implementation on the industrialization of solar drying sludge.
Study on transfer characteristics of pressure fluctuation in a prototype pump-turbine
Authors: Li J W , Liu X R
Published: January 2021

Considering unit 3 in Zhanghewan pumped storage power station as the research object, transfer characteristics of pressure fluctuation at the vaneless area were studied from the dominant frequencies, the fractional amplitude and the fractional phase at four different measuring points. It was revealed that the variation trends of pressure fractional amplitude (50Hz and 100Hz) versus output agreed well at the four points, and the phase difference between the four points varied very small with increasing of output under different water heads. This research could provide instructive inspiration for solving the vibration problems in pumped storage power station, and provide useful thinking for optimizing hydraulic design of the pump-turbine.
Comparison of acoustic-structure based one-way FSI and two-way FSI
Authors: Xia X , Zhou L J , Wang W , Zhang H R
Published: January 2021

In the numerical simulation of flow-induced vibration using two-way fluid-structure interaction (TW-FSI) method, it is usually limited by mesh deformation, and consumes a lot of computing resources. These problems can be avoided by adopting acoustic-structure based one-way FSI (ASOW-FSI) approach. The purpose of this work is to explore the applicability of ASOW-FSI, and to analyze the similarities and differences between the two dynamic response analysis methods. A series of numerical calculations are carried out for the elastically mounted rigid cylinder at low Reynolds number. By systematically comparing the results calculated by these two methods, we found that ASOW-FSI can accurately predict the response in the range of partial reduced velocity, even closer to the experimental results than TW-FSI method. The main reason for the difference between the two methods in the whole reduced velocity range is that the ASOW-FSI method can not predict the “lock-in”. Finally, the mechanism of “lock-in” in vortex-induced vibration (VIV) is analyzed by forced oscillation. The results show that the structural vibration has the ability to dominate the vortex shedding under certain conditions. If the natural mode of the structure is excited at this time, “lock-in” will occur.
Numerical simulation and stability analysis of pumping transients in the pumped-storage power plant
Authors: Zheng Yang , Chen Qijuan , Liu Wanying , Yan Donglin
Published: January 2021

The pumped-storage unit (PSU) are of great significance in modern power system for its reversible operating mechanism in both power generation and water pumping directions. Aiming at the precise numerical simulation of pumping transient processes in PSU, this paper establishes a nonlinear and characteristic method-based mathematical model of the governing system of PSU in which the hydraulic behaviours of conduit pipes, surge tanks and the pump turbine as well as the mechanical-electrical characteristics of the generator-motor are taken into consideration. In this model, local hydraulic losses in model boundaries are specifically introduced to compensate for the unmodeled errors. To verify the modelling accuracy, simulation curves under both pump failure and pump shutdown conditions are compared with the practical data. Furthermore, the hydraulic oscillations in the two transient processes have been discussed specifically.
Numerical Analysis of Sand Erosion for a Pelton Turbine injector at High Concentration
Authors: Guo B , Li Y H , Xiao Y X , Ahn S H , Wu X , Zeng C J , Wang Z W
Published: January 2021

Hydro-abrasive erosion due to sediment flow often leads to the efficiency loss, seriously vibration, and sometimes even failure for Pelton turbines. This kind of erosion can be greatly intensified when the concentration of sand increases. It is of paramount importance to study the erosion mechanism for such machines, especially in Asia, where the sand concentration in many rivers is relatively higher due to some geologically young mountains like the Himalayas. In this study, the erosion patterns of the injector have been predicted at high sand concentration. The simulated scenario was based on continuous measurement of sediment flow during the flood season in an power plant. Firstly, the three-dimensional modeling for the whole flow domain of the injector with jet has been carried out by ANSYS Fluent. The free air-water flow from the injector has been simulated with the SST k-ω turbulence model, where the VOF (volume of fluid) model was implemented to capture the air-water interface. Then after tracking the particle movement in the air-water flow by the Lagrangian method, the Mansouri model was adopted to predict the erosion patterns. The erosion mechanism was explained by detailed analysis of particle impact properties like the average hits, the impact velocity, and the impact angle. The results show that the “velocity deficit region” will reduce erosion on the needle tip. In addition, abrupt geometry change can be designed at low-velocity regions to reduce erosion. This paper can provide a better understanding of the erosion mechanism, which can help to reduce wear in future designs.
Research on the Influence of Microplastics on Marine Life
Authors: Li You , Sun Yixin , Li Jinzhen , Tang Ruikai , Miu Yifa , Ma Xiaoyi
Published: January 2021

Plastics have been produced and used by humans in large quantities since they were invented, and the resulting environmental pollution problems have become more and more serious. In recent years, researchers have found that many plastic products are not completely decomposed after being discarded, a lot of plastics form microplastics in the ocean, which poses a threat to the survival of marine life. This paper analyzes the source, types and distribution of marine microplastics, and explores the influence of microplastics on marine life.
Research on Plastic Waste Pollution Based on Coupling Model
Authors: Lian Ruhui
Published: January 2021

In order to discuss to what extent plastic waste can be reduced to reach an environmentally safe level, we establish the coupling model of safety level and reduction degree, to study the relationship between the reduction degree of plastic waste and the environment safety level. In this model, we have introduced the Public Environmental Awareness Index, the disposable plastic waste recovery rate, and the effectiveness of policies to limit the use of disposable plastic, which constitute the Plastic Waste Reduction Index (DRL). Based on this, six indicators closely related to plastic waste were determined from three aspects, which are included in the environmental safety level index (ESL) by entropy method. Then, the grading evaluation table of environmental safety level was established based on the references. And through Pearson correlation analysis, we found that the level of environmental safety and disposable plastic waste reduction has a high correlation. Then we choose the European Union as the research object, and study the changes of ESL and DRL in the past ten years. Finally, we test the model by Correlation Coefficient analysis, the results show that our model is reasonable. Then through the calculation of the critical point, in order to make the environment reach the safe level, the degree that the disposable plastic waste should be reduced is obtained.
Research on Sea Surface temperature Reconstruction from long-term MODIS data
Authors: Zhou Yan , Gai Yingying , Li Junxiao
Published: January 2021

Sea surface temperature (SST) is one of the important dynamic parameters to characterize the physical characteristics of seawater, and it is also an important basic auxiliary parameter for the quantitative observation of other ocean parameters. In view of the lack of remote sensing data mainly caused by cloud cover over the ocean, based on the long-term MODIS Aqua L3 8-day mean SST products from January 2003 to March 2015, the missing data in the East China Sea are reconstructed by Data Interpolating Empirical Orthogonal Function (DINEOF) method, and the reconstruction results are evaluated by error analysis before and after cross-validation data reconstruction. It shows that the image reconstructed by DINEOF method can reflect the temporal and spatial variation characteristics of sea surface temperature in the study area, and the root mean square error of reconstruction is 0.4272. DINEOF method can reconstruct large area missing data without any prior information and has high accuracy.
Effect of Slope on Soil Carbon Storage in Prescribed Burning -- A case study of Pinus Kesiya in Jinggu County Yunnan Province
Authors: Gao Zhongliang , Wei Jianheng , Li Zhi , Long Tengteng , Wang Qiuhua , Zhou Ruliang , Shu Lifu
Published: January 2021

Compared control forest and prescribed burning forest of six slope of humus layer thickness, loads and organic carbon storage, and these soil levels organic carbon content and carbon storage in Pinus Kesiya, and confirmed to be suitable for carrying out prescribed burning. The experimental data showed that prescribed burning before and after, humus layer thickness of FS and GS are highly statistically significant (P<0.01), others were statistically significant (P<0.05). Loads and organic carbon storage of FS are highly statistically significant (P<0.01), GS, SS, AS and DS are statistically significant (P<0.05). Soil organic carbon content of FS, GS and DS on 0-60cm level are highly statistically significant (P<0.01), others slopes are statistically significant (P<0.05), FS and GS on 20-40cm are highly statistically significant (P<0.01), BS, AS and DS are statistically significant (P<0.05), lat slope and GS on 40-60cm are highly statistically significant (P<0.01), BS is statistically significant (P<0.05). Soil organic carbon storage of SS on 0-20cm is statistically significant (P<0.05), others are highly statistically significant (P<0.01), FS, GS and DS on 20-40cm are highly statistically significant (P<0.01), BS and AS are statistically significant (P<0.05), FS on 40-60cm is highly statistically significant (P<0.01), GS, BS and DS are statistically significant (P<0.05). Prescribed burning can decrease loads in forest, and carbon sequestration in different slope is different, preferred to FS to prescribed burning, next considering GS and BS, those can gain better efficiency, prescribed burning could not be carried out in SS, AS and DS.
Study on controlling factors of Heidimiao Reservoir formation in Block T121-4 of Aonan Oilfield
Authors: Wang Yihan
Published: January 2021

There are three types of faults in Block T121-4 of Aonan Oilfield, among which the faults developed from the early Qingshankou and terminated in the Third member of Nenen are the main channels for oil-gas migration. The pre-stack inversion shows that the lame impedance slice can well reflect the reservoir morphological characteristics and the channel characteristics are obvious. During the deposition period from HIIto HI, the water body changed from deep to shallow, the sedimentary facies transitioned from lakes to deltas, and underwater shunt channels were favorable reservoirs. The formation testing results show that the distribution of oil-gas is closely related to faults and sand bodies, and is the main controlling factor of reservoir formation. The main methods of oil-gas migration are vertical migration and short- distance lateral migration. If the fault-sand coupling relationship is good, oil-gas accumulation can be obtained. The reservoir anatomy shows that there are mainly two types of reservoirs in Heidimiao reservoir in the study area, namely structural reservoir and structural lithologic reservoir.
Research method and application of sedimentary facies in oilfield development
Authors: Ma Lihui , Chen Youming , Wu Hao , Nurula Jiarela , Dong Xiangrui , Ma Linjun , Liu Canchao , Gao Wenxi
Published: January 2021

The study of reservoir sedimentary facies can better describe the reservoir and ensure the smooth implementation of production. An in-depth understanding of the specific achievements of the sedimentary facies studies in the past few years can help us more accurately grasp the development process of geology and basins, so as to effectively improve the formation efficiency of oil and gas fields and thus achieve the improvement of economic benefits. In the process of determining the non-tectonical reservoirs, the study of sedimentary facies and sedimentary environment can be realized, but the study of these two aspects is still lacking and the effect is not very good. The study of sedimentary facies has a direct impact on the development of oil and gas in Our country, this paper mainly from the main characteristics of oil and gas development, in-depth introduction of the current oil reservoir development in a specific practical situation, in-depth introduction of the sedimentary relative to the specific advantages of oil and gas development.
Design and Construction of Double-wall Steel Cofferdam in Deep Water Foundations
Authors: Zhang Xuesong , Li Wenying , Zeng Baoshan
Published: January 2021

Deep water foundation is constructed by cofferdam in bridge engineering. Safety, quality, cost, and duration of bridge construction depend on the reasonable and feasible deep water cap cofferdam design and construction scheme. “Pile first, cofferdam back” construction program of double-wall steel cofferdam for deep water cap is applied in second SongHua river bridge. The results show that structural stiffness of steel cofferdam, strength of each component both meet work requirements under the most unfavorable conditions in the life-span of the construction process. This scheme effectively solves the technical difficulties in cofferdam construction and improve the working environment of installation and subsidence process. The project is going on well and the duration of construction time is reduced. This technique serve as a helpful reference to similar engineering.
Reservoir simulation of air injection assisted in situ upgrading process via subsurface electrical heating based on the horizontal well
Authors: Pei Shufeng , Wang Qiaobo , Zhang Panfeng , Huang Lijuan , Zhang Liang , Ren Shaoran
Published: January 2021

Heat transfer rate is slow during the in-situ upgrading process (ISU) via underground electrical heating, which is suitable for developing super heavy oil and oil shale reservoir. Considering the advantages of air injection process and horizontal well technology, an air injection assisted in situ upgrading process (AAISU) based on the horizontal well have been proposed and simulated. Reservoir simulation results show that air injection can improve heat transfer rate, enhance oil recovery by 11.4% and improve the energy efficiency from 4.54 GJ/GJ to 8.15 GJ/GJ comparing to the ISU process without air injection. Heating temperature and air injection rate are important for the AAISU process. When the heating temperature increase, the heat transfer rate and oil recovery increase, however, the energy efficiency are reduced stead. As for the effect of air injection rate, when the air injection rate increase from 500-4000 m3/day, the oil recovery and energy efficiency are rise first and then dropped, and the oil recovery and energy efficiency are the greatest when the air injection rate is 1000 m3/day.
Experimental Study on Aging Performance of Polyethylene Gas Pipelines
Authors: Wang Yixi , Lin Dong , Xiang Mingli , Cui Mingwei , Liu Na
Published: January 2021

Currently, there is a lack of adequate standards for evaluating the integrity inspection cycle of polyethylene (PE) gas pipelines. In this study, a series of photo-oxidation accelerated-aging experimental tests for PE80 gas pipe samples were performed. The attenuation laws of several critical performance parameters, such as micro-morphology, tensile strength, and thermal stability tests, were established. These parameters were determined at different aging times. A novel comprehensive performance evaluation method for pipeline integrity was developed using the analytic hierarchy process, and a reasonable inspection period for pipeline integrity was identified. The results showed that the samples experienced two stages of aging: rapid aging stage and aging platform stage. During the rapid aging stage, the comprehensive evaluation index for the aging performance decreased rapidly. However, the comprehensive evaluation index for the aging performance remained almost unchanged during the aging platform stage.
Organic geochemical characteristics of diatomite in Nadanhada terrane
Authors: Li Xiunan , Zhang Zilu , He Weizhong , Wang Longyu , Cai Dongrui , Yang Jiawen , Liu Lianxue
Published: January 2021

Based on the geochemical characteristics of the siliceous rocks in the Nadanhada terrane, the abundance, type and maturity of organic matter are studied, and the source rocks in Fuyuan, Raohe and Hongqiling are comprehensively evaluated. The type of organic matter in this area is mainly type III kerogen, which is in the high over mature stage with low metamorphic degree. At present, liquid hydrocarbon can still be produced. The Qianjin depression (Fuyuan area) of Sanjiang basin is a favorable area for the exploration of Lower Jurassic cherts with high organic matter abundance, low maturity and good preservation conditions.
Modeling and Analysis of the Pressure Shock Characteristics of a Load-sensitive Hydraulic System Jointly Controlled by Pump and Valve
Authors: Liu Yiou , Lai Qiwei , Zhang Runlin , Wang Nei
Published: January 2021

By establishing the mathematical model of a Load-sensitive Hydraulic System Jointly Controlled by Pump and Valve, the systematic simulation model based on AMESim is built. The simulation results show that the a Load-sensitive Hydraulic System Jointly Controlled by Pump and Valve has different pressure shock characteristics under different load conditions, which has certain reference value for understanding, using and designing the load sensitive pump composite control system.
The Application of base isolation in a power plant structure
Authors: Fu Yanwei
Published: January 2021

In this paper, large general finite element software ABAQUS is used to contrast the isolation before and after the seismic performance of a large coal-fired power plants, the application of isolation technology in the main factory building structure has carried on the preliminary discussion. Through to the main factory building structure system of isolation design and comparison analysis, get the following conclusion: after using isolation technology, obviously improve the seismic performance of the structure, under the effect of earthquake resistance, the structure of the floor shear, layer displacement and acceleration were significantly decreased, and the upper structure under earthquake is basic to keep translation, isolation effect is obvious.
Research on Inter-provincial Power Generation Rights: a Case Study of a Province in Eastern China
Authors: Fang Cheng , Pan Ting , He Xinying , Hu Jiahua , Zhao Wen , Zhao Erdong , Zeng Ming
Published: January 2021

Trans provincial generation rights trading is an effective means to increase the consumption of renewable energy. In this paper, taking a province in East China as the research object, considering the constraints of environmental protection, generator output, transmission line maximum load and other constraints, the inter provincial generation right model is constructed. Finally, through the model, the influence of transmission channel selection and bundling ratio on generation right potential space is analyzed.
Application Study on Zero Output Technology of Low Pressure Cylinder of 350MW Supercritical Unit
Authors: Zheng Wei , Zhu Lingkai , Che Yongqiang , Guo Junshan , Lao JinXu , Li Li , Ding Junqi
Published: January 2021

In response to the requirement of national thermal power flexibility reform policy and the need of regional central heating development, a 350MW supercritical unit in a power plant has been transformed with zero output technology of low pressure cylinder. In this paper, the scope and content of low pressure cylinder zero output transformation are discussed, peak shaving and heating capacity after transformation are analyzed, the difference between operation effect and calculation result after unit transformation is compared by test, and the matters needing attention in future operation are given, which provides reference for technical transformation of low pressure cylinder zero output of other power plant units.
Design and Implementation of 10kV Distribution Network Distribution Dispatching System Based on Eclipse Development Platform
Authors: Li Xin
Published: January 2021

In order to meet people's requirements for power quality and distribution network reliability, a distribution dispatching system for urban distribution network based on Eclipse as the development platform, Oracle as the database and eOMP as the software support is developed. After the demand analysis of the distribution network, the functional structure of the system is determined, and the overall design and detailed design of the system are carried out. The rule base is constructed according to the operation rules of distribution lines, and the knowledge base of operation order expert system is represented and inferred by BP (Back Propagation) neural network model. The results show that the system runs reliably and smoothly. Through this system, the power grid company can compile and implement the normal operation mode of distribution network, draw a primary wiring diagram of the line, make maintenance plan, and carry out scheduling and operation management of relay protection and automation devices in distribution network. Thus, the system helps to improve the power supply capacity and reliability of distribution network and reduce its operation cost.