bluuebunny/crossref_metadata_2025 huggingface dataset:
Research Overview on Numerical Simulation of The Dismantling Process of Large-span Steel Structural Roof
Authors: Xiaochi Yang
Published: December 2020

The dismantling of large-span steel roof is a complex evolutionary process involving redistribution of internal force. In order to ensure conformity of the structural internal forces to the design, safety and reliability during the demolition, it is necessary to make accurate simulation analysis of the dismantling process to determine a reasonable dismantling plan. With a review of the simulation methods adopted in the dismantling process of large-span steel structure and analysis of the relevant research results, this paper elaborates on advantages, disadvantages and adaptability of each method, which can serve as a basis for the study of roof dismantling.
Temperature effect on preparation of water-Storage ceramic foam with vanadium-titanium magnetite tailings
Authors: Li Lin , Jiang Tao , Zhou Mi , Chen Bojian , Chen Chao
Published: December 2020

Massive accumulation of vanadium-titanium magnetite tailings (VTMT)—a kind of common industrial solid wastes—will pose enormous harms to both ecological environment and economic development. Based on the preparation of water-storage ceramic foam by taking full advantages of 50 wt% VTMT and 50 wt% waste glass, the effect of sintering temperature on the sample performance was further investigated through a test, and the foaming mechanism at high temperature was deeply probed. The results show that as the sintering temperature rises, the bulk density and compressive strength of the sample gradually decline, its water absorption per volume reaches the maximum value and the average pore diameter inside the sample is gradually increasing. The optimal sinter temperature is 1,040 °C, and the water absorption, bulk density and compressive strength of the sample are 56.5%, 0.26 g/cm3 and 0.68 MPa, respectively.
Calculation method of production pressure drop based on BP neural network velocity pipe string production in CBM wells
Authors: Zhu Hongying , Qi Yaoguang , Zhang Fenna , YunfeiSong  , LiangLin  , Zhang Jian
Published: December 2020

In the stable production stage CBM wells have the characteristics of high gas production and low water production. The use of continuous velocity tube technology for drainage can achieve better drainage results. Accurate and rapid prediction of the pressure drop of velocity pipe string production in a coalbed methane well has become the key to the operation and management of velocity pipe technology. This paper uses the nonlinear mapping and prediction capabilities of the BP neural network to build a three-layer BP neural network to construct a velocity pipe string production pressure drop prediction model. The model is based on gas production, water production, bottom hole pressure, pipe string diameter, and well depth. The five factors are input, and the pressure drop of the pipe string is the output, which can quickly and accurately realize the pressure drop analysis and calculation of the speed pipe drainage. The analysis shows that it is feasible to use the BP neural network to calculate and analyse the pressure drop of the velocity string of coalbed methane wells.
New Energy Generation Converter Harmonic Evaluation Based on Operation Data
Authors: Nan Wang , Yan Cheng , Ti Guan , Qiang Ma , Yujie Geng , Shibo Wang , Jiawei Xing , Shumin Sun
Published: December 2020

The research on the harmonic mechanism and features of new energy generation units is crucial for ensuring safe and stable operation of new energy generation. In this paper, a big data analysis method suitable for the operation data of new energy power plant is used to analyse the harmonics generated by PWM modulation and dead zone effect of switching devices and the interharmonics generated by DC side voltage fluctuation. The simulation analysis verifies the harmonic characteristics of new energy power converter, the model basis of new energy power generation operation evaluation and power grid connection certification.
A novel approach of Landsat 8 imagery to predict PM2.5 concentrations in a south-eastern coastal city of China
Authors: Yang Lijuan
Published: December 2020

Satellite remote sensing data with moderate-to high-resolution has been commonly used in deriving spatial coverage of PM2.5 concentrations in urban areas. Previous studies focusing on city-scale PM2.5 estimation mainly retrieved aerosol optical depth from moderate-to high-resolution remote sensing data. In this study, the spectral response experiment was carried out to explore the sensitivity of spectral wavelengths to PM2.5 concentrations in Fuzhou, China. The results showed that the near-infrared reflectance was much more sensitive to PM2.5 than other wavelengths. We also found that the difference vegetation index (DVI) presented higher correlation with PM2.5 than other indexes. A linear mixed effects (LME) model was then developed to explain the variability of PM2.5, and the results showed that the overall R2
of LME model using DVI and meteorological parameters reached 0.80 with RMSE of 7.82 μg/m3. The results suggested that the proposed LME model using DVI from Landsat 8 OLI could be effectively used for predicting PM2.5 in a city scale.
Comparative Study on Performance of SOFC/GT and SOFC/SCO2 Turbine Combined Cycle System
Authors: Xingsheng Lao , Mengran Liao , MaCan  , Chunhui Dai
Published: December 2020

In order to compare and study the performance of SOFC/SCO2 cycle and SOFC/GT cycle, the efficiency of SOFC/GT cycle under the same working temperature and the middle temperature and low temperature SOFC/SCO2 combined cycle system was compared and analyzed. The cycle parameters of the non-pressurized SOFC/SCO2 system at the highest efficiency are retrieved by genetic algorithm. The research results show that the efficiency of the SOFC/SCO2 combined cycle is about 5% lower than the efficiency of the SOFC/GT cycle under medium temperature conditions. Under low temperature conditions, the efficiency of the SOFC/SCO2 combined cycle is about 4% higher than the efficiency of the SOFC/GT cycle in all operating conditions.
A simple analysis of the relationship between Taiyuan pollutant concentration and time
Authors: Cai YiLuo , Wang ChuHan
Published: December 2020

In the context of today’s growing emphasis on environmental issues, the paper analyses 2018 pollutant data from eight sites in Taiyuan. The relationship between PM2.5 concentration and time (season, month, week) was analyzed by the R language, and the reason for PM2.5 concentration variation was inferred. Air Pressure, wind speed, precipitation, and vehicle restrictions all affect the concentration of pollutants.
Study on the control strategy of chaotic oscillation of synchronous generator based on the linear feedback adaptive fuzzy sliding mode control
Authors: ZhuoqunZhao  , HongjunWang  , HuiZhao
Published: December 2020

In the case of periodic load disturbance, the chaos oscillation phenomena may be caused by synchronous generator to threaten the safety operation of the network. In order to solve this problem, this paper presents the strategy on the control of linear feedback adaptive fuzzy siding mode. Under the action of the controller, the system output track the desired trajectory, and the fuzzy control rules are used to suppress the high frequency chattering in conventional sliding mode controller. The theoretical analysis and simulation results show that the designed controller can effectively control the power system oscillation, and it has certain robustness.
Comprehensive Evaluation of Power Grid Security and Benefit Based on BWM Entropy Weight TOPSIS Method
Authors: Zhao Lang , Li Hui , Wang Zhidong , Peng Dong , Xue Yawei , Ai Xin
Published: December 2020

With the gradual integration of various forms of energy, the energy utilization rate has increased and it also brings great challenges to grid evaluation. Therefore, the use of scientific and reasonable comprehensive evaluation method can provide effective help for the development of power grid. In order to solve the problem that the traditional single evaluation method is used in the comprehensive evaluation of power grid, resulting in too strong subjective awareness and lack of evaluation of the objective original data itself and uneven weight distribution, this paper proposes that Nash equilibrium solution is introduced into BWM entropy weight as the goal of coordination and optimization. In the method, the comprehensive weight is calculated, and the distance between the selected scheme and the ideal scheme is sorted by TOPSIS. This method combines all the information of objective data to balance the subjective and objective weight. Through this method, 16 indicators of safety and benefit in 25 provinces in 2017 of State Grid Economic Research Institute are analyzed, and the feasibility of this method is verified.
A Virtual Power Plant Load Curve Clustering Method Based on Improved K-means Algorithm and Its Application
Authors: Li Hui , Zhao Lang , Peng Dong , Wang Zhidong , Wang Xueying , Ai Xin
Published: December 2020

In view of how virtual power plants can effectively participate in power grid operation, a method of load curve clustering of virtual power plants based on principal component analysis reduction and aggregation level clustering and k-means clustering is proposed, and the application of clustering results is studied. Firstly, combined with the data obtained from the information physical network, the principal component analysis method is adopted to analyze the characteristics of different loads participating in the virtual power plant aggregation, so as to standardize the data and reduce the dimension. Then, the algorithm combining aggregation hierarchical clustering and k-means clustering is used to cluster all load output curves participating in the aggregation, to obtain load curve clusters of the same class and find out the clustering center. Finally, the clustering results are analyzed, and the corresponding evaluation system is established. Through comprehensive evaluation, appropriate load combinations are selected to participate in the virtual power plant aggregation.
Study of Smoke prevention and Exhaust System for High-rise Buildings
Authors: Kunhua Xiao
Published: December 2020

Nowadays, the smoke prevention and exhaust system has not been effectively taken seriously, but smoke in fire disasters have become an important cause of death. In this paper, some problems still exist in smoke prevention and exhaust system will be concluded including design inspection and maintains. Meanwhile, a new method of calculating volumetric flow rate of smoke exhaust in high-rise building will be shown. The results show that the the existing prevention and exhaust systems in high-rise buildings have some defects and need to be upgraded. Outdoor wind in high-rise buildings is an important effect of fires. Some significant and easily ignored aspects of inspection and maintains will also be summarized.
Research on well pattern optimization for secondary development of new layer system in old oilfield
Authors: Xia Wang , Qihao Hu , Lifang Jiao , Fan Zhang , Xianqiu Chao , Yuhong Du , Yuyang Han
Published: December 2020

The Es3 reservoir of Jin45 fault block has been developed for many years, and now it is faced with problems such as high water content, serious casing damage. In order to change the current development status of Jin45 fault block, the Es2 reservoir is put into development which located in the upper part of Es3 reservoir. The well pattern direction, well pattern form and well pattern density of Es2 reservoir are optimized by various methods in this study. On the basis of Es2 reservoir well pattern optimization study, the new well pattern of Es2 reservoir and the old well pattern of Es3 reservoir are comprehensively considered and compatibly adjusted. While the new well pattern is put into development, the injection-production system of the old well pattern is improved by using the new drilling wells, and the potential remaining oil is exploited, which lays a foundation for the efficient development of the old oilfield.
Experiment Analysis of CAN-FD Factors
Authors: Xu Ye , Cheng Ximing , Ruan Xusong
Published: December 2020

With the growing number of onboard ECUs, the load of classical CAN (Controller Area Network) is aggravated to produce transmission delay issue. A new protocol CAN-FD (Controller Area Network with Flexible Data-Rate) was presented by the BOSCH company to meet the high speed and real-time data exchange needs of the intelligent vehicles and ITS (Intelligent Transport System). For the vehicle electronics, the CAN-FD data network is still growing up. In this paper, the classical CAN and CAN-FD in protocol are compared through experiments. Results show that: (1) the terminal resistors have more effects on the CAN-FD than the CAN; (2) the bit rate of the CAN-FD can be ten times of that of the CAN; and (3) the data transmission efficiency of the CAN-FD network is affected by both the bit rate and the data length. Additionally, the physical network configuration takes decisive effect on the minimum frame interval of the CAN-FD frame.
The influence of Cd Content Transported by Different Sources on Different Surface and Bottom Layers
Authors: Yang Dongfang , Yang Dong , Ling Weifeng , Lin Dong , Li Haixia
Published: December 2020

According to the investigation data of Jiaozhou Bay in 1992, the vertical distribution, horizontal distribution and seasonal variation of Cd in the surface and bottom waters from the center of the bay to the south of the mouth of Jiaozhou Bay are studied, and the seasonal distribution, range of distribution and horizontal distribution trend are determined. The results show that in May, August and October, in the waters from southern mouth to the center of the bay, the Cd content of surface and bottom waters ranged from 0.12-1.19μg/L, in line with the national water quality standards for Class I and Class II seawater, which indicates that water quality was slightly polluted by the Cd content orwas not polluted. The surface levels of Cd vary seasonally from low to high: spring, summer, and fall, the same was true for Cd seasonal variation in bottom waters. In the surface and bottom waters of Jiaozhou Bay from the south of the bay mouth to the center of the bay, in May, August and October, when the Cd content in surface waters was relatively low, and the corresponding bottom layer was relatively low; when the Cd in surface waterswas relatively high, the corresponding bottom layer was relatively high; this shows that the loss of Cd content both from the surface and the bottom was relatively high. In May, August and October, in the waters from the southeast of the bay to the center of the bay, the horizontal distribution of Cd in the surface and the bottom waters have an opposite trend. From May to October, the seasonal variation of Cd content in surface waters in the southeast of the bay was mainly affected by the Cd content transported by main sea currents, while the bottom waters are mainly affected by river-transported Cd content. From May to October, in the central waters of Jiaozhou Bay, the seasonal changes of surface and bottom Cd content are not consistent withthat of Cd content transported by main sea currents. On the temporal scale, in the waters of Jiaozhou Bay from the south of the bay to the center of the bay, in May, August and October, the Cd content in the surface and bottom watersvariateswithin the same range, maintaining the consistency. On the spatial scale, in the waters from the southeast of the bay to the center of the bay, in May, August and October, according to the comparison between the Cd content transported by main sea currents and that transported by rivers, it can be proved that the horizontal distribution of Cd content in the surface waters was opposite to that of in the bottom waters.
The Charging Characteristics of Electric Vehicle Group Under the Mode of Shared Travel
Authors: Chen Chongchen , Wu Zhigang , Zhu Junliang , Su Entong
Published: December 2020

In the future, travel revolutions such as shared travel will bring great changes to the structure of transportation, and the charging characteristics of electric vehicle will also be affected. This paper takes the new travel mode as the research background and models the driving and charging behavior of electric vehicle group. Then the multi-agent technology is used to build a large-scale electric vehicle group simulation model. This model fully considers the capacity constraints of traffic network and charging station, which can be used to simulate the actual behavior of electric vehicle group. Finally, the charging load curve of the electric vehicle group under the new travel mode is obtained based on simulation. The result shows that as the proportion of shared travel increases, the daily average charging load keeps increasing, and the charging load peak comes earlier and lasts longer.
Research on the Development and Innovation of Animation Industry in Jilin Province in the Internet Big Data Era
Authors: Liu Kun , Sun Xing Qu
Published: December 2020

China has entered the era of informatization of big data on the Internet. The Internet has subtly influenced people’s study, work and life, and even influenced the process of social development. At present, China is moving from a big Internet user country to a strong Internet technology country. The development of the Internet industry has been scaled up, and its application field is gradually becoming multi-dimensional. Today’s animation industry, as a new format for the development of cultural and creative industries, is facing business opportunities and challenges. Traditional communication methods have been unable to meet the development needs of the market, and animation companies have begun to turn to the field of new media networks. Europe, Japan and developed countries such as the animation industry development history tells us that the animation industry development not only is relying on the overall planning of the industrial chain, rational distribution, but also the full use of the Internet in big data, the development of new media technology to build a platform for the development, transformation and upgrading Industrial operation model.
Calculation of influence range of impact holing on the adjacent railway
Authors: Feng Zhongju , Yin Jixing , Chen Jinhua , Guo Suizhu , Wu min
Published: December 2020

In order to solve the impact of actual construction projects on the existing surrounding environment, the impact and vibration of the impact on the existing railway subgrade stability caused by the construction of the bridge foundation are analyzed. Based on the actual case of the construction project of No. 37 main pier across the Jiaoji Railway Main Bridge at Binlai expressway, the influence of the impact holing on the adjacent railway is analyzed. The influence range of the construction vibration is based on the Chinese Seismic Intensity Scale (GB/T 17742-2008) and Safety Regulations for Blasting (GB6722-2014), and taking the maximum velocity allowable value as criterion, the minimum safety range of impact drilling is obtained. Using the theory of small hole expansion to calculate the influence of the effect of soil compaction, the minimum allowable value of safe distance for the Construction technology of impact forming hole is considered 6.5m; in addition, based on the numerical simulation of nonlinear time history analysis, a reasonable exciting force parameter is given for practical engineering. The influence of impact amplitude A and impact frequency f on construction safety distance is analyzed. The results show that: The minimum safety distance of impact drilling is linear with the increase of impact amplitude A. When the impact frequency f is greater than 10Hz, the minimum safety distance tends to a fixed value as f increases. The results of this study guide the actual construction of the field, it guarantees the normal traffic of the Jiaoji Railway and provides a theoretical support for similar projects.
Modeling of well-seismic structure
Authors: Wenchao Liu
Published: December 2020

The characteristics of the fault system are analyzed by using the 3D method and the combination of well-seismic and break-point method. The structural model is established by using the combination of logging and seismic data, to guide the adjustment of oilfield development. The results show that the fault combination, fault orientation and Extension Direction are obviously different from those before, and the large structure pattern of the study area has not changed, a structural model based on the combination of logging and seismic data, which is faithful to the well point data and retains the relative trend of seismic data, is better than the model based on logging data, it’s more like an underground structure.
Research on 4D Visualized Dynamic Construction of BIM Building Decoration
Authors: Xin-yao Huang , Shu-Fen Yang , Kun-Fa Lee
Published: December 2020

BIM visualization 4D technology is applied to residential decoration and decoration construction sites, to establish Project and Revit model perspective analysis through Autodest Navisworks software, and make personalized modifications according to the different needs of customers to meet the current internal needs of fashionable buildings and dynamic decoration.
Experimental Study on Mechanical Properties of Soft Clay under Different Stress Paths
Authors: Lu Yuan , Ke Wenhui , Huang Xiangguo , Xiao Mingzhao , Chen Bin , Huang Juehao , Chen Jian
Published: December 2020

In actual engineering, when the soil element is subjected to load, the stress state will change accordingly. In this paper, undrained triaxial stress path tests for Ningbo reshaped saturated soft clay under different confining pressures are carried out. The test uses the GDS bidirectional vibrating triaxial instrument. The stress path dependence of saturated soft clay is studied. The stress-strain relationship and undrained shear strength under different stress path conditions are mainly analyzed. The test results show that the stress-strain relationship of the stress path test is obviously non-linear, basically strain hardening. The stress-strain curves of saturated remolded soft clay under different stress paths and consolidation pressures can be expressed in hyperbolic form. The initial stiffness E0 basically increases with the increase of the deflection angle of the stress path. The test results have certain reference significance for foundation pit and tunnel engineering.
Pricing and incentive strategy for construction supply chain w ith carbon emission sensitive heterogeneous demand and gove rnment subsidies
Authors: Jiang Wen , Wang Lu , Shi Kanfeng
Published: December 2020

Based on consumers’ purchase intention, this paper obtains the utility function of carbon emission sensitive heterogeneous consumers and establishes a two-level supply chain model composed of the owner and the contractor under the government subsidy. Based on the principle of maximizing the profits of each member of the supply chain, the optimal pricing, incentive intensity and emission reduction effort level of the owners and contractors are obtained. On this basis, the influences of government subsidies, customer composition ratio and carbon sensitivity on the owner’s optimal decision are analyzed. The results show that, with the increase of government subsidies for the contractor emission reduction costs, the proportion of carbon emission-sensitive consumers and the carbon sensitivity of consumers will increase, and the market demand will be increased, which will not only improve the profits of owners and contractors, but also the contractors’ emission reduction efforts. It can provide decision-making reference for enterprise product pricing, emission reduction and government subsidies.
Study on development characteristics of horizontal freezing temperature field in subway connecting passage
Authors: Yu Changyi , Lu Mingyue
Published: December 2020

The freezing method is often used in underground excavation projects with high requirements for water stop and support. However, with the increasing complexity of the project, the freezing form is becoming more and more complex, and it is difficult to calculate the temperature field law by theoretical analysis. As a powerful simulation method, numerical calculation can be used to simulate the development of temperature field in complex horizontal freezing engineering. Based on the horizontal freezing construction of a subway connecting passage, this paper analyzes the development characteristics of horizontal freezing temperature field, and the results are in good agreement with the measured data. It is proved that the numerical simulation method can be used to simulate this kind of project, and the results can be used to guide the design and construction of related projects.
Study on temporal and spatial variation of temperature field in horizontal freezing and thawing settlement
Authors: Yu Changyi , Lu Mingyue
Published: December 2020

Artificial freezing method is commonly used in underground engineering excavation, such as mine, foundation pit and subway. The problem of post-construction thaw settlement has attracted more and more attention, but it is difficult to calculate the development law of thaw temperature field of complex frozen curtain by analytical method. Therefore, this paper adopts numerical method to study this problem. In this paper, taking the horizontal freezing construction of a subway connecting passage as an example, the development law of temperature field in the melting process is analyzed, and the results are basically consistent with the measured data. As a general means, numerical simulation is feasible to simulate the development law of temperature field in horizontal melting of complex curtain. The results of this paper can be used to guide the design and construction of artificial freezing.
Study on temporal and spatial distribution law of thaw settlement displacement by horizontal freezing method
Authors: Yu Changyi , Lu Mingyue
Published: December 2020

After freezing construction, the damage caused by thawing settlement mainly comes from the displacement and settlement of strata, which leads to uneven settlement of underground pipelines and surface buildings in the project area. In this paper, based on the three-dimensional finite element analysis, the settlement displacement field of artificial frozen soil in a subway connecting passage is analyzed, and the parameters such as elastic modulus, density and specific heat change with temperature are considered in the model. The change of mechanical parameters in the soil layer is given by the temperature field, which makes the mechanical parameters of each point in the soil layer different. In addition, the temperature field of the soil layer changes with time, and finally makes the mechanical parameters change point by point, so as to ensure that the simulated melting and settlement calculation process is more in line with the actual working conditions. The calculation results of settlement displacement show that the settlement displacement field of soil layer changes nonlinearly with time and space. The research results of this paper provide reference for the position and time node of the control measures of thawing settlement.
lastic time history analysis of a super tall building
Authors: Zhou ChangXian , Zheng ShaoPeng , Ye YouQuan , Wang Hao , Fu Ping
Published: December 2020

in this paper, the principle of elastic time history analysis and the selection of seismic wave in time history analysis are briefly described; the elastic time history analysis of a super high-rise building is carried out by using the SATWE software of PKPM. The analysis results show that the base shear force and other indexes of the structure meet the requirements of the code under the action of 7-degree multiple intensity earthquake, and can meet the seismic design standards of the current seismic code in China.
Simulation of water quality data for advanced treatment of domestic sewage in constructed wetlands
Authors: Wang Yuelei , Han Yancheng , Zhou Xinyue , Fang Panbo , Chen Sihan
Published: December 2020

With the gradual maturity of sewage treatment technology, constructed wetlands are increasingly employed to treat sewage. In residential areas where people live, there are concentrated sewage discharges. Therefore, the author proposes constructing several small movable constructed wetlands in the community to treat domestic sewage in the community. A 40 cm× 40 cm model was established to simulate the removal effect of pollutants. The influent concentrations of simulated COD, NH4
+-N, NO3
−, TP are 96.01 mg/L, 18.23 mg/L, 14.13 mg/L, 3.00 mg/L, respectively, and the outlet concentrations are 18.25 mg/L, 5.51 mg/L, 3.12 mg/L, 0.32 mg/L, the removal efficiency reached 80.99 %, 69.78 %, 77.92 %, 89.33 %, with good simulation effect. It provides a theoretical basis for the construction of constructed wetland.
Analysis of Rainfall-Runoff Variation Characteristics and Influencing Factors in the Dawen River Basin in the Past 50 Years
Authors: Shen Zhen Tao , Zhao Qiang , Li XiFeng
Published: December 2020

Based on the hydrological data of Daicunba Hydrological Station of Dawen River from 1966 to 2017 and the meteorological data of surrounding stations, this paper analyzes the characteristics of the interannual variation of rainfall and runoff in the basin, and discusses the effects of rainfall and human activities on runoff. The results show that: (1) Rainfall and runoff in the Dawen River Basin showed an insignificant upward trend, with rising rates of 0.9541mm/a and 0.5398mm/a respectively; (2) Rainfall has a cycle of 4, 7, and 22 years, of which 22 The annual cycle is the main cycle, and the runoff has a cycle of 5, 7, 18, and 22 years, of which 22 years are the main cycle, and the main cycle of rainfall and runoff is consistent; the rainfall mutation point occurred in 1997 and 2002, and the runoff mutation point occurred in In 2002, the runoff had a significant increase trend after the sudden change; (3) According to the sudden change point of the runoff, the study area was divided into the base period (1966-2002) and the change period (2003-2017), so as to obtain the change of human activities on the runoff. The contribution rate is 60.6%, and the contribution rate of rainfall to runoff is 39.4%, indicating that the runoff of the Dawen River Basin is mainly affected by human activities.
A new literature search model for multi data objective programming
Authors: Kan Li
Published: December 2020

Aiming at the problem that the current literature search algorithms only provide literature clues and original texts, which can not realize the analysis and evaluation, it is the formal comparison and cannot compare the actual contents of new papers and existing literatures; the objective programming target algorithm is introduced to calculate the “copy ratio” of the substantive content by minimizing the deviation between the objective function and the target value; small sample verification is carried out It is feasible and can open up a new idea for the upgrading of literature search tools.
Metallogeny of the Jinyu Graphite Deposit, Sichuan Province
Authors: Yang Yongqiang , Wan Pingyi , Wang Guanghong , Peng Zhaoqiang , Liu Bo , Xie Yunbo , Lv Xiaoping , Chen Jun
Published: December 2020

Graphite deposit is important ore in Huili County, Sichuan Province. It is located in the middle part of the Kangdian axis and the middle part of the Kangdian basement fault uplift zone. The graphite deposit is located in the strata of the Dayingshan Formation of the Lower Proterozoic Hekou Group. The deposit belongs to sedimentary metamorphic graphite deposit formed under the dual factors of regional and thermal contact metamorphism. The ore body is strictly controlled by horizons. Graphite is composed of migmatized graphite quartz schist ore and migmatized graphite schist ore. The former is of the main type and the latter to the second type. Through comparative analysis of metallogenic geological and geophysical characteristics, it is considered that the gold rain graphite deposit is influenced by strata, structure, magmatic rocks, metamorphism, migmatization and other factors.
A CFD simulation and experimental study: predicting heat transfer performance using SST k-ω turbulence model
Authors: Widiawaty C D , Siswantara A I , Budiarso  , Gunadi G G R , Pujowidodo H , Syafei M H G
Published: December 2020

The heat exchanger is the most common equipment in the industry. Nowadays, CFD simulation has been used widely to predict the performance of heat transfer. The accuracy of the CFD depends on several factors such as simulation parameters, models, and quality of the grid. The heat exchanger in industrial application has big heat transfer capacity, since it consists lot of tube and big shell size. In this study, the fluid heat transfer on the tube is represented by uniform wall tube temperature. The objective of this works is to evaluate the performance of the SST kco turbulent and by applying heat transfer simulation of fluid on the tube side represented by uniform wall tube temperature. This present work compared CFD simulation and Experimental study. While the working fluids which are used in the experimental study are cooking oil in the shell and exhaust gas in the tubes. The constant of SST kw turbulent are cmu: 0.09, c1: 1.44, c2: 1.92, and sigma epsilon 1.3. The CFD simulation result shows in 50 s simulation that the temperature of cooking oil is from 48 °C to 54 °C. This tendency has good agreement with the experimental study.
The cooling effect of polycrystalline type PV panels using perforated aluminum plates
Authors: Bizzy I , Sipahutar R , Puspitasari D , Sofijan A , Fajri M A
Published: December 2020

A study has been conducted to improve the efficiency of Polycrystalline type PV panels. This research was conducted at the Energy Technology Research Laboratory, Engineering Faculty, Sriwijaya University, South Sumatra, Indonesia. The disadvantage of PV panel, when receiving solar radiation, it will increase the temperature of the PV panel but decrease the efficiency. This study uses a perforated aluminum plate with hole diameter of 2.5 mm. The plate is placed behind the PV panel. The dimensions of the plate are 960 mm x 600 mm x 20 mm and the number of holes of 1457. The specifications of PV panels are 1020 mm x 670 mm x 30 mm, Polycrystalline type PV panels, maximum power of 100 WP. The results showed that the PV panels given a perforated aluminum plate cooling had higher efficiency than those not given perforated plate cooling.
Effect of cutting conditions on power demand and surface roughness through sustainable turning of mild carbon steel
Authors: Risal Syah , Nur Rusdi , Halik Razak Arthur , Kondo Yan
Published: December 2020

Sustainable turning is a lathe machining process to carry out production in particular by paying attention to the sustainability of machinery without reducing production output. The machining process is done by optimizing the turning process parameters when carrying out the cutting process on medium carbon steel. Some parameters affect the lathe process, including speed, feed rate, and cooling. The purpose of this study was to determine the machining conditions in order to optimize the electric power consumption and surface roughness of the medium carbon steel turning process. The research method used was experimental and analysed using the ANOVA method. From the results of the research, it was concluded that the minimum electricity consumption was obtained in the process of turning steel St 42 without cooling with a speed of 237 rpm and a feeding of 0.157 mm/rev. The lower surface roughness was obtained in the turning process of St 60 steel with a rotation speed of 840 rpm and a feed rate of 0.157 mm/rev. The results of data analysis using ANOVA analysis method to get optimal conditions in order to minimum power demand and low surface roughness at 425 rpm of speed and 0.052 mm/rev of feed rate.
Preliminary study to determine the maximum safe speed of vehicles based on rolling moments and vehicle skid to reduce of driving accidents
Authors: Sumarsono D A , Siregar R , Adhitya M , Nazaruddin N , Prasetya S , Zainuri F , Heryana G
Published: December 2020

Indonesia is one of the countries with the highest death rate due to road traffic accidents. Research on vehicle safety needs to be done immediately. Some travel companies, rental vehicles, and tourism vehicles have made permit speed regulations, but the basis for selecting these limits is not scientific. In this study will be presented how to determine the maximum speed allowed in a vehicle scientifically, and how to calculate the speed of the permit can be a reference to other vehicles. This research method is analytical and experimental methods. The normal force of the wheel when the vehicle turns will be different, where the normal force of the wheel inside will first be lifted due to rolling force, and will have an impact on the skid that might occur. So, this is becoming a reference in calculating the vehicle’s maximum clearance speed. The maximum speed allowed of the vehicle under study depends on the turning radius. Therefore, knowing the wheel’s normal force from various conditions and the maximum speed of the vehicle, a safety warning system can be developed in the future to avoid vehicle accidents.
Extremely high surface area of activated carbon originated from sugarcane bagasse
Authors: Dwiyaniti Murie , Elang Barruna A.G , Muhamad Naufal R , Subiyanto Iyan , Setiabudy Rudy , Hudaya Chairul
Published: December 2020

In this study, the extremely high specific surface area of activated carbon originated from sugarcane bagasse was produced by dry chemical activation. In this process, KOH was used as a chemical agent and directly mixed sugarcane bagasse carbon with KOH powder, which has been treated in a solid form. In particular, the influences of the impregnation ratio and activation temperature were investigated. The as-prepared activated carbons were characterized by Brunauer-Emmet-Teller (BET), which aims to determine the surface area of activated carbon and Raman Spectra analysis to examine the vibration modes of material characteristics. The maximum specific surface area of the activated carbon reached 3554 m2/g at 800 °C and an impregnation ratio of 1:4. Furthermore, the Raman spectra of activated carbon exhibited graphite structure for sample in impregnation ratio 1:2 and 1:3 due to having of G and G−1band. This material is essential for make battery.
Performance analysis and evaluation of a 10.6 kWp grid-connected photovoltaic system in Serpong
Authors: Nurdiana E , Subiyanto I , Indarto A , Riza  , Wibisono G , Hudaya C
Published: December 2020

The grid-connected Photovoltaic (PV) System was installed in the rooftop of Energi Building, PUSPIPTEK in 2017 located in Serpong, South Tangerang. The System consists of 40 modules @265 Wp, a 10 kWh battery system, and a 10250 kW grid-tie inverter. This study presents the performance analysis of the PV system based on the eight-months monitored data from July 2019 to February 2020. The evaluated parameters of the PV system include yields, performance ratio, capacity factor, energy efficiency, and average daily energy output of the PV system. The results show that the average value of the performance ratio and capacity factor during the eight-months monitored period were 82.42% and 14.07% with average values of the array (Ya), final (Yf
) and reference (Yr
) yields were 3.49 kWh/kWp/d, 3.38 kWh/kWp/d, and 4.12 kWh/kWp/d, respectively. Meanwhile, the average daily energy output of the PV system during the eight-months monitored period was 36.92 kWh per day with the average values of the module (ƞPV), system (ƞsys), and inverter (ƞinv
) efficiency was found to be 15.29%, 14.77%, and 96.63%, respectively. Compared with previous studies in the literature, these results indicated that the grid-connected PV system installed in Energi Building PUSPIPTEK Serpong exhibited good performance.
Improvement of small scale turbine performance: in West Aceh region using a clark-y type of turbine blades
Authors: Saputra Maidi , Sartika Rika
Published: December 2020

This study aims to improve the performance of small scale wind turbines in the West Aceh region using a Clark-Y type turbine blade. Aceh Barat is one of the districts in Aceh province which is located at coordinates 04°06´ - 04°47´ NL and 95°52´ - 96°30´ EL and an area is located on the west coast of Aceh province bordering directly on the Indian Ocean, and one of the areas are worst affected by the tsunami disaster in 2004. The reference data shows that the potential of wind energy in the West Aceh region on average is quite varied, which is the lowest of 3.4 m/s to the highest speed of 5.8 m/s. The results of tests on the turbine blades before and after optimization provide increasing the ability of the turbine to produce energy and mechanical power. Based on the characteristics of the rotor rotation, the highest rotation data that occurs on the blades before the optimization is 316.6 rpm, and the highest rotor rotation on the blades after optimization is 361.3 rpm. Accordingly, there is an increase in turbine capability by 12.4%.
Experimental study of cascaded thermoelectric generators with differences in focal length using LED lights energy radiation
Authors: Muhtar Kamaludin Tutang , Awal Syahrani S , Danny Syamsu W , Basri  , Mustofa
Published: December 2020

The length of concentration focus to the cascaded thermoelectric generator (TEG) module determines the power of the output along the entire surface of the heated side receiving the thermal radiation. LED-type (Lighting Emitting Diode) bulb with low power 10, 15, and 20 Watt shown that the emitted lights also contain the thermal that can generate electricity on the TEG. The experiment results show that the 20 Watt lamp with a concentration focus of 110 mm has the highest power and efficiency (2.5%), while the efficiency of 15 and 10 Watt bulbs is 1.2 and 1.6%, respectively. The significant amount of bulb power used by consumers today has the potential to be the source of new and renewable energy to produce electricity. Although the amount of power still small, it can be used to charge mobile phones and power banks.
Biodiesel characteristics of tuna fish bio-oil waste in the transesterification process with variation of reaction time and stirring speed
Authors: Rosyadi I , Caturwati Ni Ketut , Satria Dhimas , Haryadi  , Muzaky
Published: December 2020

Waste from fishery production from canned fish production in Indonesia is very abundant, this waste can be used as raw material for making biodiesel. In this research, the production of biodiesel from tuna oil waste is carried out through the transesterification process. The purpose of this study was to determine levels of Free Fatty Acid, the effect of reaction time and stirring speed on the transesterification process on the characteristics of biodiesel. Fixed variables used consisted of methanol plus bio-oil in a ratio (6: 1), methanol at a concentration of 98%, reaction temperature of 60 °C, KOH catalyst weighing 3.5 grams, while the independent variable consisted of the time of transesterification reaction and stirring speed. The variation of transesterification reaction time used is 1, 2, and 3 hours while the variation of the speed of stirring the transesterification reaction is 160, 245, and 360 rpm. The optimal conditions obtained were 2 hours reaction time and 360 rpm stirring speed with biodiesel characteristics, namely a density of 849 kg / m ^ 3, viscosity of 3.53 cSt, water content of 0.6%, calorific value of 9,390 cal / gr, flash point 84 ° C, and acid number 3.6343 mg KOH / gr.
The study of corrosion behaviour api 5l steel in sea water using immersion test method
Authors: Saefuloh I , Kanani N , Rukmayadi Y , Noor M I , Yusuf Y , Setiawan I , ula S , Abdullah S , Notonegoro H A
Published: December 2020

API 5L steel, a low carbon steel with a high alloy content, is often used as an underwater construction material or oil and gas pipeline. Banten has a wide sea area and has a long coastline where part of the coastline is used for petrochemical industries. There are three coast areas of Banten, namely Bayah Rangkasbitung, Anyer and Merak, that are used for petrochemical industries. Most of those industries use API 5L steel for underwater construction materials and pipes to channel seawater, chemical compounds, gas and oil. Whereas, seawater will greatly affect the lifetime of API 5L construction steel because it can cause corrosion. The purpose of this study is to analyze the corrosion characteristics of API 5L steel affected by the environment of seawater media and the temperature of seawater in accordance with its natural conditions. The samples of API 5L steel were immersed in seawater media with variation of immersion time of 5, 10, 15 Days and variation of immersion temperature of 20°C, 40°C, and 60°C. In this study, a series of tests were carried out, namely immersion test, weight loss test, and SEM test (Scanning Electron Microscopy). The highest corrosion rate on API 5L steel is 0.39 mmpy which belongs to Merak’s seawater media in the immersion time of 15 Days and the temperature of 60°C, while the lowest corrosion rate on the API 5L steel is 0.013 mmpy which belongs to Bayah’s seawater media with a time of immersion of 10 Days and a temperature of 20°C.
Stress analysis on the frame holder of generator translation motion on horizontal direction for sea wave power plant using finite element method (fem)
Authors: Indriani A. , Hendra  , Yenni S. , Aswata W. , Rispandi  , Hernadewita  , Tanjung A.
Published: December 2020

The generator is a machine component that converts mechanical energy into electrical energy. Generators can be found in power generation systems. In this paper, generators are used on the sea wave power plants [1-4]. This generator works by utilizing the effects of ocean waves that rise and fall so as to push the piston to move in the same direction with ocean waves. The performance of the generator is influenced by the magnitude of the force of the piston, rotors and stator. Stable, rigid and smooth piston movements also can increase generator output performance. The design and material of the generator holder is very influential on the generator stiffness. Generator stiffness includes deformation and stress that occur and can be obtained using the finite element method (FEM) [5-13]. In this paper focus on simulating the generator holder shape horizontal direction and the amount of deformation and stresses by varying frame holder generator shape and inclination (750, 800, 900). In previous studies, the translational motion generator frame holder design is less rigid (stable). From the simulation results, the maximum voltage value (σmax) of von mises is 6,427 MPa, the deflection value is 61.29 mm with 900 generator stand design positions.
Development of drying machine to improve palm sugar quality
Authors: Erwin Erwin , Meutia
Published: December 2020

One variant of palm sugar products is sugar in the form of powder or often called brown sugar, which is of good quality is bright yellow sugar, with a strong special aroma and a uniform and dry crystal size according to (Indonesian nation standardized) SNI 01-3743-1995 maximum allowable water content is 3%. An artificial drying machine is needed to speed up the process of separating the water content in sugar. This machine is designed with a tiered rack with a heating source. The temperature regulation uses thermostat, the way it works is by electrically charged elements to heating air, and directing hot air into the drying chamber by using fan (fan blower) and (exhaust fan) for air circulation. The quality to be achieved in the experiment is sugar with a maximum water content of 3%. Experiments were carried out several times with brown sugar that has been matched in grain size. Drying time is very important, because this time is related to production capacity and energy consumption. The remaining water content is less than 3% according to the needs of the planning, the tool is functioning properly.