bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficiency of zinc ions (II) adsorption using activated carbon from palm kernel shell
Authors: Jitjamnong J , Luengnaruemitchai A , Kongrit N , Kasetsomboon N , Khantikulanon N
Published: April 2020

The adsorption of wastewater from various industrial sources is important and one of the dangerous challenges the environment. This study focuses on the investigation of the efficiency of zinc ions adsorption by using activated carbon in synthetic wastewater. Activated carbon was prepared from palm kernel shells that were obtained from Songkhla province, Thailand. Activated carbon was prepared from palm kernel shells containing sodium chloride as a catalyst at the ratio 1:0, 1:1 and 1:2 (w/w), respectively. Activated carbon was calcined at 700 °C for 2 h. Next, it was washed with hot distillate water until pH = 7. After that, it was dried at 105 °C for 24 h. Iodine number was analyzed by using CHNS/O analyzer. The concentration of solution was examined by using atomic absorption spectrophotometer (AAS). The prepared activated carbon was characterized by thermogravimetric analysis (TGA), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), X-ray fluorescence spectrophotometer (XRF), X-ray diffractometry (XRD) and Fourier-transform infrared spectroscopy (FTIR). For the pure activated carbon, it was noteworthy that the major components were O (37.25%), N (30.95%) and C (26.54%), whilst a minor content was H (2.23%), C (1.73%) and Si (0.76%). This result was strongly consistent with the XRF analysis. The ratio of activated carbon to sodium chloride 1:2 (w/w) exhibited the highest iodine number (180.95±10.82 mg/g). The factors of adsorption including initial concentration (20-150 ppm) and adsorption time (2-10 h.) The result showed that the optimum conditions of adsorption containing concentration were 65 ppm and adsorption time was 10 h. The efficiency of adsorption was 69.73 %.
Treatment of laundry wastewater using chemically treated sugarcane bagasse
Authors: Ayu Haslija A.B , Abdulrazzak Rabee
Published: April 2020

Laundry wastewater constitutes of detergent compounds, bleaching agent, textile color pigments and dirt. These compounds are hazardous once discharged into the water source without proper treatment due to the adverse effects on the aquatic life in the freshwater bodies. This fixed-bed column adsorption study using the natural biomass from chemically treated sugarcane bagasse is proven to be effective for the removal of constituents present in the laundry wastewater. The synthetic laundry wastewater was prepared in the laboratory from a powder type of detergent with a concentration of 50mg/L and 250mg/L to be further used in the adsorption process. The characteristics of the synthetic laundry wastewater were analyzed by the turbidity, pH, dissolved oxygen (DO) and chemical oxygen demand (COD). The fixed-bed column experiment with the treated sugarcane bagasse was conducted under different parameters such as the effect of pH, initial concentration and bed height. The best removal efficiency was observed at a bed height of 10 cm with a concentration of 50 mg/L is 65%, followed by 33% and 20% for bed heights of 4 and 2 cm respectively. As for the concentration of 250 mg/L, the best removal efficiency was at a bed height of 10 cm which was found to be 58% followed by 26% and 17% removal for a bed height of 4 cm and 2 cm respectively. The kinetics of the adsorption was investigated using the kinetic models of Thomas and Yoon-Nelson. The experimental results fitted well on the Thomas model and Yoon-Nelson which showed a high linear regression value greater than 0.9. These results prove that chemically treated sugarcane bagasse is an effective low-cost adsorbent for reducing turbidity, pH, COD and increasing the DO concentration.
Engineering properties of ancient masonry materials in Thailand and substitution materials for historical structures preservation
Authors: Mahasuwanchai Peerasit , Wonganan Natthanan , Athisakul Chainarong , Tangchirapat Weerachart , Sahamitmongkol Raktipong , Leelataviwat Sutat
Published: April 2020

This paper presents the engineering properties of ancient masonry materials and substitution materials for the preservation of Thai historical structures. The study was divided into 2 parts. For the first part, the ancient masonry materials including brick and mortar were collected from various historical sites in Bangkok and Ayutthaya provinces. The engineering properties of masonry materials were evaluated in laboratory such as compressive strength, density, chemical compositions, porosity, and water absorption. The second part was investigation to find the suitable substitution materials for historical repair mortars. Fly ash was used as a pozzolanic materials to partial replace slaked lime for making historical repair mortar. The engineering properties of historical repair mortar containing were also evaluated and compared with the ancient masonry materials obtained from the first part. The binder to sand ratio was controlled at 1:3 by weight. The slaked lime was substituted by fly ash in the ranges of 10-30% by weight. The experimental results showed that the use fly ash to a partial replace slaked lime could decrease the setting time of historical repair mortar. The compressive strength of historical repair mortars with fly ash were ranged from 1.54-2.22 MPa, depending on the level of replacement, while that of the ancient masonry materials had the compressive strength of 1.88-2.71 MPa.
Synthesis and characterization of reduced graphene oxide-iron oxide nanocomposite as a potential fuel cell electrocatalyst
Authors: Yusoff F. , Suresh K. , Noorashikin M. S.
Published: April 2020

Driven by the high demand for commercialization of fuel cell (FC) technology, a design of potential oxygen reduction reaction electrocatalayst based on reduced graphene oxide (rGO) and iron oxide (Fe3O4) nanocomposite has been described and denoted as rGO/Fe3O4.The nanocomposite was synthesized by means of facile one-pot process. The resultant rGO/Fe3O4was physically and electrochemically characterized by using Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffractrogram (XRD), Scanning Electron Microscopy (SEM), Cyclic Voltammetry, (CV) and Electrochemical Impedance Spectroscopy (EIS). The FTIR analysis shows the formation of rGO/Fe3O4from the presence of C=C, C-C and Fe-O bonds in the spectrum of the indicating the synthesis material is successfully obtained. XRD analysis also confirms the presence of rGO and Fe3O4in the composite by hematite structure indexed peak of diffractogram. Scanning Electron Microscopy (SEM) image depicts the attachments Fe3O4onto the surfaces of rGO. The composite was then dissolved in the solvent and drop-casted on the glassy carbon electrode (GCE) for electrochemical analysis. Cyclic Voltammetry (CV) shows increment in current responses of nearly two and half folds for rGO/Fe3O4/GCE compared to bare GCE. Electrochemical Impedance Spectroscopy (EIS) shows a stable electron transfers process with lower charge transfer resistance (Rct) of the nanocomposite modified electrode which due to the synergistic effect between rGO and Fe3O4.The results of the analysis show the compound could be a promising candidate as an electrocatalyst for fuel cell.
Integrated algal biorefinery and palm oil milling for bioenergy, biomaterials and biopharmaceuticals
Authors: Abdullah M A , Hussein H A
Published: April 2020

The call for greener processes and eco-friendly products has been the essence of the 2030’s core agenda on 17 Sustainable Development Goals. The major challenge is in bringing systems thinking and holistic worldview to the planning and strategies to develop the Economics whilst incorporating the Environment, and Socio-cultural diversity dimension as equal components. This means a total revamp of human activities such that the discussion on climate change, famine and poverty, destruction of eco-systems and habitat for wildlife, and the emerging infectious diseases, is as relevant as, if not more important than, discussing about artificial intelligence, robotics, flying and driver-less vehicles, and exploration to Mars. There is an urgent need for resource optimization, better biodiversity management and improved agro-practices for food production and distribution, affordable health care, and cleaner energy, air and water, with strict monitoring, regulation and enforcement to minimize emission, pollution and wastage. The focus of this presentation is to highlight research and development efforts towards the realization of sustainable bioenergy production, environmental remediation and conversion into biomaterials via integrated algal biorefinery and palm oil milling processes. Recent development in microalgal research with nanotechnology for biopharmaceuticals and anti-cancer products will be discussed. The image problem and the negative perception surrounding oil palm industries especially with regards to the impact on the environment, and the efforts towards a more sustainable production route will be highlighted. This hopefully could bring forth insights towards partnerships and collaboration among the industrialists, investors, economists, scientists, engineers, and social scientists to tackle the immediate and pressing problems facing the Planet and the People, whilst reaping the Profit, yesterday, today and tomorrow.
Hydrogen adsorption on calcium-decorated planar aluminene using density functional theory
Authors: Bayasen D S , Villagracia A R , Pedrosa G R , Lin H , Ong H L , David M , Arboleda N
Published: April 2020

With the rising demand for clean energy, the concept of hydrogen economy has grown more popular, and with this popularity the need for better hydrogen storage materials increases. Decorated surface materials such as planar hexagonal aluminene are being studied to determine their potential as good hydrogen storage materials. This study theoretically investigates hydrogen adsorption on aluminene decorated with calcium, where calcium is binded on the top, bridge and hollow sites of aluminene using density functional theory. Results on decoration adsorption have shown that calcium can easily bind a distance of 1.80 Å to 2.80 Å on the top, bridge and hollow sites with binding energies of 1.85 eV, 2.01 eV, and 3.32 eV, respectively. The density of states of the calcium-decorated surface show that its electronic property is generally maintained with zero magnetization. Small amount of charges were adsorbed from the aluminium atoms to the calcium atom based on the charge difference. This leads to hydrogen molecule adsorption with low adsorption energies ranging from 34.13 meV to 80.51 meV. In addition, minimal broadening of energy levels were shown by the density of states. With these results, it can be concluded that planar hexagonal aluminene with low concentration of calcium atoms may lower the hydrogen capacity of aluminene.
Self-made electromagnetic vibration energy harvester of different stroke length and number of coil turns
Authors: Bin Jamsari Shahrul Azhar , Quen Lee Kee , Kang Hooi-Siang , Tey Wah Yen , Lee Kiat Moon , Tan Lit-Ken
Published: April 2020

This paper presents the experimental work on a new tube-shape electromagnetic vibration energy harvester to obtain its optimum peak-to-peak voltage output based on different stroke length, number of coil turns and optimum frequency. The harvester is fabricated using Acrylonitrile Butadiene Styrene (ABS) material. It consists of housings with three different stroke lengths, top and bottom covers, Neodymium Iron Boron (NdFeB) magnets, spring and copper coil. The tested stroke lengths are 40 mm, 45 mm and 50 mm while the number of coil turns are 10, 20 and 30. A standard energy harvesting circuit which consists of full-wave bridge rectifier and a capacitor is designed and fabricated to conduct this experiment. The importance of this circuit is to convert alternating current (AC) to direct current (DC) as well as to enable harvesting and storing processes of electrical energy. The harvester is tested on external vertical vibrations generated by shaker with frequency ranged from 5 Hz to 50 Hz with interval of 5 Hz. The raw voltage readings have been extracted from Oscilloscope and are analysed using Microsoft Excel and Octave software. From the results obtained, the optimum peak-to-peak voltage harvested is 39.41 mV at resonant frequency of 5 Hz by 50 mm stroke length and 30 coil turns device. The higher the stroke length and number of coil turns, the higher the peak-to-peak voltage can be harvested.
Microscale structure designing of nanoparticle-based photocatalyst films for enhanced functionalities and efficient energy utilization
Authors: Kameya Yuki , Yabe Hiroki
Published: April 2020

Photocatalysts have increasingly become important materials to utilize renewable solar energy for decomposing pollutants, producing clean water, achieving self-cleaning surface, and so on. Therefore, it is desirable to expand the applications of photocatalysts by enhancing the functionalities and allowing ample design flexibility. Here the potential of nanoparticle-based photocatalyst films with microscale surface structures was investigated in order to enhance their useful functionalities. Photocatalyst films with microscale surface structures were prepared using the suspension of titanium dioxide (TiO2) nanoparticles. The micro-scale structural features of prepared films were evaluated using a scanning electron microscope. Also, an atomic force microscope (AFM) was used. The AFM analysis of a film consisting of nanoparticle spherical aggregates revealed a surface profile of subwavelength surface structure. Then the optical and wetting characteristics were investigated. It was found that the visible-light transmittance increased due to subwavelength surface structures and that the microstructured TiO2films exhibited the contact angles below 10 degrees, i.e., superhydrophilic behavior, without ultraviolet-light illumination. On the basis of the presented results, it was suggested that the microscale surface structures of photocatalyst film can be designed to achieve enhanced functionalities. It is expected to effectively utilize the energy of sunlight in many applications using functional photocatalyst films with optimized design.
Production of high quality empty fruit bunch pellet by water washing and torrefaction
Authors: Krerkkaiwan Supachita , Boonbumrung Duangkamol
Published: April 2020

EFB pellet is the high potential biomass for combustion process due to the relatively high heating value and the high availability in the Southern of Thailand. However, the containing of high unwanted minerals, especially K and Cl is the main drawback of EFB pellet which causing the ash fouling or/and slagging during the combustion. In this study, the high quality EFB pellets (low K, low Cl, high heating value) were produced by applying the water washing and torrefaction methods. For water washing treatment, the effect of water and acetic acid solution on the mineral content of EFB pellet was studied. In addition, the effect of torrefaction temperature (250, 280 and 300 °C) on the quality of EFB pellet was investigated. Results revealed that the ash content of the washed EFB decreased from 5.3 % to 3.0 % and 0.7 % by washing with tap water and acetic acid solution, respectively. Comparing with the raw EFB pellet, K and Cl in ash were significantly reduced by washing about 60 % and 88 %, respectively. Heating value of the EFB and washed EFB pellet were increased after torrefaction with the higher temperature. The water washed EFB pellet and torrefied at 300 °C gave the highest heating value about 24.3 MJ/kg. It was 33% increased HHV when comparing with raw EFB pellet.
Quality improvement of syngas from gasification process of palm kernel using NiO/CaO catalysts on ceramic supporter in coupled with biochar absorbent from agricultural residues
Authors: Rattanahirun S , Khamwichit A , Dechapanya W
Published: April 2020

In this study, palm kernel shells were utilized in the gasification process to produce syngas. In addition, biochar prepared from pyrolysis of the left-over mangosteen and durian peels were used in the gasification process to enhance the tar removal efficiency. The expected outcomes of this study could result in not only the generation of renewable energy from but also the waste utilization of agricultural residues. The effect of catalysts and biochar on the syngas quality improvement were particularly studied. Palm kernel shell was used as raw material. The compositions and heating values of the biomass were characterized by the proximate, ultimate, and bomb analyses, respectively. Syngas was produced from a downdraft gasifier connected with catalytic and adsorption units in sequence. The gasification process was operated with 1 kg of palm shell per batch at a fixed air flow rate of 25 L/min. The NiO/CaO (10 %wt) catalysts on ceramic supporter with various NiO contents of 2%, 4%, and 8% were synthesized by co-impregnation. Biochars were synthesized by pyrolysis process of durian and mangosteen peels at around 300 - 500 °C for 2 hrs. Morphology and compositions of the synthesized catalysts and biochar were analyzed. The results of SEM analysis showed that the NiO and CaO were deposited and well dispersed on the porous ceramic ring supporters. The presence of active NiO on the catalyst was also confirmed in FTIR result with (wavelength of 692 cm−1). Biochar from durian and mangosteen peels, with BET surface area of 0.9219 - 0.9989 m2/g and adsorption pore size of 11.193 - 11.912 nm, were obtained from a pyrolysis process at 400 - 700 °C. The syngas samples were collected from the gasification unit every 15 min to 60 min. The gas chromatography was used to analyze the syngas compositions. The GC results indicated that increasing NiO contents in the catalysts tended to result in increasing CH4 composition of the syngas for both systems with and without biochar. With tar filtration unit containing biochar, the ability of tar removal was significantly increased by 2 to 9 times comparing to the system without biochar.
Effects of aquifers on soil temperature distribution around deep buried heat exchanger
Authors: Zhang Y P , Jia G S , Ma Z D , Xia Z H , Cao Y. , Jin L W
Published: April 2020

Deep buried heat exchanger has been increasingly applied into the building heat source through the utilization of geothermal energy. During the geothermal system design process, the aquifer is an important factor that affects the overall performance prediction. The flow of underground water at different positions changes the temperature distribution of the soils around the buried pipe and then influences the heat exchange at different depths. Consequently, the variation of the temperature field causes the thermal radius of the heat exchanger no longer regularly distributed, which affects the determination of the well spacing. With the aims of improving the accuracy of performance estimation, the aquifer effect is carried out by this study. The solution to the moving line source theory is used to acquire the temperature response at different positions. The overall effect of the underground water with different velocities on the performance is evaluated. The soil temperature distribution in the heat exchange zone with aquifers at different depths is studied in detail. The predicted thermal influence radius at different depths with various groundwater velocities and soil thermal properties showed that the temperature distribution around the buried heat exchanger is largely influenced by the groundwater movement. Under the simulation condition, the thermal radius increases from less than 10 m for pure conduction condition to a maximum value of 25.3 m with groundwater flow. The aquifer enhances the heat absorption of the heat exchanger, but the high flow rate also leads to a large thermal radius. The obtained thermal influence radius under different conditions can provide guidance for the design of the geothermal system.
An analytical model for vertical-butted geothermal well with different groundwater flow directions
Authors: Jia G S , Ma Z D , Jin L W , Zhang Y P , Cao Y , Meng X Z
Published: April 2020

Geothermal has become a popular renewable energy in recent decades due to its properties of non-polluting, clean and large reserves. The vertical-butted geothermal well is a new structure for geothermal utilization. Two vertical boreholes with a certain distance are connected at bottoms by directional drilling to form a U-shape circulation loop. Due to the existence of the aquifers, the movement of underground water extends the heat exchange range and affects the geothermal system performance. This paper aims to develop an analytical method to solve the soil temperature field around the vertical-butted geothermal well with different flow directions. Taking the interacted effect of the two parallel pipes on the surrounding soil into consideration, the temperature distribution in the heat exchange zone is obtained. It is found that the temperature field changes significantly when the groundwater flow exists. The movement of underground water extends the downstream thermal radii from 4.8 m to 10.7 m, 10.6 m and 11.7 m when the flow directions are 0°, 45° and 90° toward the axis of the two pipes, respectively. The upstream thermal radii reduce from 5.4 m to 1.9 m for all the cases with groundwater movement. In addition, the effect of the underground water flow direction on the temperature field around the butted wells is analyzed. The results show that when the groundwater flow direction is perpendicular to the axis of the two pipes, the temperature field is the most beneficial to the performance of the vertical-butted geothermal well.
Geothermal resources in southern Thailand – part of a renewable energy mix
Authors: Duerrast Helmut
Published: April 2020

Electrical energy demand for Southern Thailand is continuously increasing partly due to an increase in tourism. Around 3,000 MW of coal fired power plants are planned by the government, but the proposal was put on hold due to the resistance of local communities and civil society groups. Besides this, coal fired power plants are not only large CO2 emitters, thus intensifying the on-going climate change processes, but also require lengthy environmental impact assessments, and their technology costs remain stagnant at comparable high levels. Solar and wind energy can be produced at far lower costs than coal, however, their shares on the renewable energy mix are comparable small in Thailand, but with a steady increase. A disadvantage of solar and wind energy production is that the production is not constant due to day/night and weather, respectively. These disadvantages can be compensated by adding geothermal energy, as this energy from deeper geological sources is continuously reaching the Earth’s surface. This allows the continuous feed to geothermal power plants which by this can act as a backbone of a renewable energy mix. In Southern Thailand hot springs from the north to the south are the surface expressions of active geothermal systems at depth. Surface exit temperatures can reach up to 80 degree Celsius, thus considered as low enthalpy resources, which can be utilized applying state-of-the-art binary power plant technology. In the current renewable power plan of the government geothermal energy is not considered due to the low availability of this resource. However, recent research has shown that Southern Thailand holds promising quantities of geothermal resources; with further scientific investigations needed. Finally, the only current geothermal power plant in Thailand located in Fang, Northern Thailand, is situated close to a national park in a beautiful landscape and environment, thus acting as a positive example for Southern Thailand.
Network reconfiguration and optimal allocation of distributed generations for Mayangone distribution system
Authors: Mon Khine Khine , Htay Tin Tin , Lin Ohn Zin
Published: April 2020

This paper focuses on reconfiguration of radial distribution system incorporated with optimal allocation of Distributed Generation units (DGs). The network reconfiguration is to optimize the structure of radial feeders by changing the status of normally closed sectionalizing and normally open tie switches. The optimal allocation of DGs in distribution system has to determine the DGs location and their correspondent sizing for enhancing the system effectively. There are many investigations with both two researches either separately or incorporated simultaneously. But network reconfiguration by using Particle Swarm Optimization (PSO) incorporated with optimal allocation of DGs based on Voltage Stability Index (VSI) and analytical approach of Forward Backward Sweep (FBS) method in radial power flow is the novelty of this research. The main objective is to achieve the minimum losses and improvement of voltage profile while all distribution constraints are satisfied. In proposed algorithm, optimal allocation is determined by finding the best sizing and location of DGs based on VSI and FBS load flow, and then PSO reconfiguration finds out the optimal location of tie and sectionalizing switches simultaneously. The study of test system is carried out on Mayangone Distribution System (MDS) and the obtained results are inefficient for this research.
Geothermal characteristics of two deep U-shaped downhole heat exchangers in the Weihe Basin, China
Authors: Zhang Y. P. , Huang S. P. , Meng X. Z. , Jia G.S. , Yang F. , Zhou C.
Published: April 2020

Geothermal resources are abundant in the Weihe Basin, which provides great potential for winter district heating in the Guanzhong area in western China. As a demonstration project for deep geothermal exploitation and utilization, four boreholes of over 2,000 m were drilled and paired to form two U-shaped downhole heat exchangers (DHEs) in the Xi’an Depression of the Weihe Basin. In this paper, the borehole equilibrium temperatures of these two DHEs, measured two years after the systems had been completed, are presented. The analysis of the borehole temperatures show that: (1) the thermal and hydrological regimes of the study area are stable, as indicated by the highly consistent borehole temperatures among the four boreholes, both horizontally and vertically. (2) the geothermal gradient range down to the depth of 2,000 m in this area is 3.45 ˜ 3.47°C/hm with an average of 3.46 ± 0.01°C/hm, substantially higher than the regional mean and implying a great geothermal energy exploitation potential; the high geothermal gradient anomaly can be attributed to the rather thin crust in the Weihe Basin with a relatively high mantle heat flow and hydrothermal convection systems involving fluid circulation in nearby discordogenic fault zones. (3) the Lantian-Bahe Formation has the features of stable distribution, good aquifer yield, high transmissivity, high permeability and high thermal conductivity, and hence, it is a good hosting stratum to the horizontal section of U-shaped DHEs in this area to maximize heat exchange efficiency and sustainability.
The use of artificial neural networks (ANN) in the prediction of energy consumption of air-source heat pump in retrofit residential housing
Authors: Ye K.K. , Demirezen Gulsun , Fung A.S. , Janssen E.
Published: April 2020

Machine learning algorithms using Artificial Neural Network (ANN) were developed to predict the performance of heat pump systems in retrofit residential housing. The study attempts to address the research gap in the application of machine learning algorithms to real-life field measurements as a case study. Rowhouse units with electric resistance baseboard heating were retrofitted with Ductless Air Source Heat Pumps (DASHPs). Sensors were installed to collect the energy consumption data during the baseboard and DASHP monitoring periods. Linear and quadratic regression methods following the International Performance Measurement and Verification Protocol (IPMVP) were applied to predict energy consumption based on outdoor temperature and heating degree days. These predictions were compared against results from ANN models based on Levenberg-Marquardt algorithms using the hour of the day, day of the week, outdoor temperature, wind speed and direction, relative humidity, condition and indoor temperature as inputs. Preliminary results indicate that predictions from ANN models produced higher correlation of determination than those from IPMVP regression analysis.
Performance of graphene-based hydrogel in oil removal using graphene oxide derived from powder and flake graphite
Authors: Ng L.Y. , Lee J.J. , Ng C.Y. , Mahmoudi E. , Hairom N.H.H. , Ong C.B.
Published: April 2020

Graphene-based hydrogel had been formed by chemical reduction process of graphene oxide using ascorbic acid as a reducing agent in this study. Oil adsorption capacity of the hydrogels that were synthesized using different parameters, including type of graphene oxide feedstocks (powder or flake graphite), concentration of graphene oxide used (2 mg/mL or 5 mg/mL), as well as the amount of ascorbic acid added into the graphene oxide (5 grams or 8 grams), had been evaluated in this work. Fourier Transform Infrared Spectroscopy (FTIR) results showed that the oxygen-containing functional groups which were initially present in the graphene oxide could be removed or reduced to form the 3-dimensional π-π interactions hydrogel. In overall, hydrogel produced from flake graphene oxide with the use of higher concentration of graphene oxide (5 mg/mL) and the lower amount of ascorbic acid (5 g), showed the best performance in oil adsorption capacity. The hydrogel produced from these parameters showed the highest adsorption capacity of 7.90 g of oil adsorb per g of hydrogel. This study has provided useful information on the functional groups of graphene-based hydrogels in addition to their oil adsorption capability.
Particle Swarm Optimization based Power Control Algorithms for SWIPT-Assisted D2D Communications Underlaying Cellular Networks
Authors: Xia Xueyao , Kang Guixia
Published: April 2020

We studied power control algorithms for SWIPT-assisted D2D communications underlaying cellular networks in this paper. The particle swarm optimization (PSO) based power control algorithm is put forward to mitigate the interference and enhance the sum throughput of D2D networks. In order to avoid falling into the local optimum, we combined simulated annealing with particle swarm optimization(SA-PSO) to improve performance of the algorithm. The main idea is to allocate proper transmitting powers to D2D links while maximizing the total throughput. Unlike other related works, the transmitting power and the power splitting ratio are both optimized in this paper. Simulation results demonstrate our algorithms are conductive to boosting the total throughput of D2D networks. The PSO and SA-PSO based algorithms outperform the game-theory based algorithm in terms of the sum throughput of D2D networks.
Situation Projection Based on Multi-time-scale Recursive Dynamic State Estimation
Authors: Li Liangzi , Li KeJun , Sun Kaiqi , Liu Zhijie , Liu Wentao
Published: April 2020

In order to solve the problem of lacking of situation awareness in smart distribution network, this paper proposed a real-time situation projection method for distribution network based on multi-time-scale dynamic state estimation. Based on hybrid measurement including micro PMU, a multi-time-scale recursive dynamic state estimation was realized through recursive transformation between state projection and pseudo measurement. A pseudo measurement Correction algorithm is implemented in the proposed state estimation loop to increase the estimation accuracy. Utilizing the historic states data calculated from the proposed state-measurement recursive dynamic state estimation, a novel real-time situation projection method is proposed in this paper. With the modelling of partitioned multivariate time series analysis, the proposed situation projection method is achieved by predicting the situation indexes for the distribution network operator in real time. Simulation validates the feasibility of the proposed method to improve the situation awareness level in the distribution network.
Research on Three-phase Ground Fault Diagnosis Technology Based on Two Terminal Measurement Points
Authors: Yao Zheng , Hu Yutao , Yu Xin , Mei Suzhen , Si Hongxiao , Yu Xiaochen
Published: April 2020

Because the distribution power network is very complex, and easy to cause trouble, The signal is too small to be submerged in the noise, So it is hard to find where the fault is from the branches. based on the distributed parameter model of transmission lines, this paper proposes a fault location method of multi branch distribution lines based on the distributed parameter model of transmission lines. It will affect the whole network to generate faults. Find the fault line through network analysis, and then find the fault point on that line through calculation The simulation results prove the correctness and accuracy of this method, and provide a theoretical basis for the fault location of distribution lines.
Research on ADRC of Double Buck Inverter
Authors: Zhang Zixi , Xiong Hejin , Tang Rongjiang
Published: April 2020

The traditional double buck full bridge inverter adopts the hysteresis current control mode, and the current is in the half cycle. Because of its no bridge arm through, high voltage utilization and high efficiency, it is widely used. Based on the disturbance caused by power supply fluctuation, external noise and system parameter change, this paper proposes an auto disturbance rejection control (ADRC) strategy. The simulation results show that the ADRC strategy can make the double buck full bridge inverter have good waveform tracking performance, good robustness, stability and high accuracy.
Design of Multi-band Circularly Polarized Microstrip Antenna
Authors: Han Qinghua , Shi Mingdeng
Published: April 2020

Design a multi-band circularly polarized microstrip antenna for ISM (2.4GHz, 5.8GHz) and WiMAX (3.3GHz-3.6GHz).Using Ansoft HFSS15.0 for the simulation analysis, The size of the resonance point and the resonance bandwidth are adjusted by opening four triangular grooves on four sides of the radiation patch. The simulation results show that the frequency band of the antenna’s return loss below -10dB is 2.38GHz-2.52GHz,3.37GHz-3.45GHz, and 5.6GHz-5.9GHz. The antenna meets the design requirements of multi-frequency and miniaturization.
Research on Multi-target Signal Separation and Processing Method
Authors: Lv Hong , Li Jun , Xu Hongfeng , Sun Quanling
Published: April 2020

Nowadays, intelligent cities and transportation are being implemented in major cities around the world. In unmanned vehicles, autonomous identification and separation of moving targets is the essential and important part of intelligent transportation. This paper proposes a multi-object separation algorithm in order to solve the security problems that can promote smart transportation. This paper deals with multi-target signals based on MATLAB. In terms of distance, between the cars (targets) that can be separated, multiple targets are separated by matched filter and FFT algorithm, then the performance of the research is expressed by distance resolution. The separable target distance is up to 200 m, and the resolution is up to 0.6 m; in the terms of speed, multiple targets are separated by the Doppler transform, then the performance of the research is reflected in the form of speed resolution. The speed at which the separated target can be identified is up to 200km/h, and the resolution is up to 1.8km/h, otherwise, both stationary and moving targets can be identified. Finally, all the results are obtained by MTALAB simulation.
Trajectory Prediction Based on Machine Learning
Authors: Su Lumin , Li Li
Published: April 2020

With the rapid development of the Internet and positioning technology, trajectory prediction has become a popular research direction because of its wide range of application scenarios. However, the trajectory points are represented only by a series of incomprehensible numerical labels in current studies, and the extraction of the stay points are also lack of time consistency. On the other hand, conventional trajectory prediction models do not make full use of the trajectory context information, as well as only predict the position of the next stay points, which limits the prediction accuracy. To fulfill the above problems, the trajectory prediction method based on machine learning is studied. In this paper, a spatial information extraction method based on multistage cluster is proposed, as well as the LSTM model and the bidirectional LSTM model in the deep learning are used to predict the next position. Experimental results show that the novel method proposed can better represent the semantic information of trajectory and improve the prediction performance greatly.
Dilated Residual Spatial Attentive Generative Adversarial Network for Single Image De-raining
Authors: Xing Junyao , Bi Xiaojun
Published: April 2020

This paper propose a dilated residual spatial attentive generative adversarial network for single image de-raining. The improved spatial attentive mechanism is combined with the dilated convolution residual module to optimize the Condition Generative Adversarial Network(CGAN) structure, to solve two problems still exist in the task of removing rain from a single image: First, the rain streaks contained in the dataset we can use are limited, and in the case of real rainy days, the rain streak density is diverse, it is impossible to simulate them completely and accurately. Then, the existing rain removal models cannot remove rain streaks properly for images with different rain streak density which attend to over or under rain removal. In our methods, Firstly, the dilated convolution module is used to enhance the feature extraction of rain streaks, and then an attention map is generated by the spatial attention mechanism module to accurately locate the position of rain streaks, and the rain streaks are extracted as the foreground information by combining the two parts of the network to guide the subsequent rain removal operation; Then the rain streaks is removed through the Contextual auto-encoder, combining with PatchGAN discriminator. The experimental results on two synthetic dataset and real-world rain image show that the network model proposed in this paper has high generalization ability under different rainfall conditions. it improves the rain removal effect of the model on the most realistic public dataset, and improves the recovery ability of image details while effectively removing rain on other public datasets, which verifies the effectiveness of the model in improving the generalization ability and improving the image quality after rain removal. At the same time, the effect of rain removal is better than other methods on the real rain images, which proves that the method proposed in this paper has high practical application value.
Development of Networked NC Practical Training System
Authors: Fan Hongmei , Zhang Chuncheng
Published: April 2020

With the development of information technology, networked education has become the trend. It is one of the effective measures to solve many problems in higher education to make full use of the modern information technology educational resources and to carry out the professional teaching based on network widely. To meet the needs of networked teaching and experiments of NC(Numeric Control) principle course, this paper develops a web-based NC practical training system based on WINDOWS operating system, which uses Tomcat to build a WEB server, and uses JAVA language to manage ORACLE database. The networked NC practical training system provides a good platform for the students majoring in numeric control. This platform can not only deepen their understanding and mastery of numerical control expertise, but also cultivate their ability of system design and development.
Comprehensive Evaluation Method of Office Building Energy Consumption Based on Improved Multi-index
Authors: Chai Kang , Yu Junqi , Tian Ying , Zhao Anjun , Gao Jiaojiao , Nie Jikai
Published: April 2020

In view of the imperfection in the selection of energy consumption characteristics and energy conservation evaluation methods, this paper proposes an energy consumption analysis and energy conservation evaluation method suitable for office buildings. Through the analysis of office building energy consumption monitoring layer data, establishing standard of building energy consumption data sets, including office building day by day, month by month, year after year way of energy consumption and heating and cooling is analyzed, and aiming at the problem of building energy efficiency evaluation index weights are difficult to determine the, combined with the feature of energy consumption was proposed to build multiple indexes comprehensive evaluation of energy consumption. Through the example of office building, the evaluation results are verified, which proves that this method can evaluate the energy consumption of buildings reasonably and feasible, and provides a new idea for the comprehensive evaluation of building energy conservation.
Graph-Theoretic Models for the Holistic Analysis of Actor-Networks with Emergent Properties
Authors: Tselykh Alexey , Denisov Boris
Published: April 2020

This paper presents the results of a research in modeling a concept of a black box and a mechanism of translation in sociotechnical actor-networks with emergent properties based on the extended and powerful formalisms of hypergraphs, directed hypergraphs, hypernetworks, metagraphs, and nested metagraphs. We introduce graph-theoretical models that allow for systemic studies and holistic analysis of actor-networks using rich mathematical apparatus of a set theory. The main object of the research are actor-networks in Science and Technology Studies. We hope that our contribution to the arsenal of graphical presentation tools and rigorous mathematical models for actor-network analysis will encourage the transition from qualitative to quantitative studies and the wider practical application of actor-network theory.
Independency of Knowledge Diffusion Analyzed by Inverse Citation Networks
Authors: Chi Qiaozheng , Ma Yinghong
Published: April 2020

With the development of worldwide knowledge-based economy, structures of knowledge diffusion in scientific research have become extremely complex and dynamic. Properly evaluating the knowledge diffusion would encourage authors to pursue high quality researches. Hence, this paper presents a novel metric of independency of knowledge diffusion (IKD) on the published paper v, defined as the ratio of citation counts of v without its references’ to citation counts of v and its references’ minus their commons’. Utilizing the inverse citation network formed by published papers in American Physical Society (APS) from 1997 and 2016, the experimental results show that the distributions of IKD are following power law behaviors and the values of IKD are affected by citation counts and involved cooperative institutions. It is reasonable to assess the performances of knowledge diffusion by the metric of IKD.
Research on Financial Software Selection Decisions Based on a Fuzzy Evaluation Model
Authors: Shao Changyan , Xu Sheng , Wang Xiaojia
Published: April 2020

Appropriate financial software is the foundation of strengthening the enterprise information construction. For enterprises, choosing appropriate financial software is not only conducive to improving the efficiency and profitability of business processing, but also to ensuring the authenticity of financial information and the accuracy of decision-making. In this paper, we first established an evaluation index system of financial software evaluation, and then combined two-dimensional uncertain linguistic variables (2DULV) and grey relational analysis (GRA) to evaluate and select the financial software. Finally, the effectiveness of the proposed 2DULV-GRA model is verified by an example of an enterprise. The fuzzy evaluation model proposed in this paper allows decision-makers to express uncertainty, which provides a reference for the enterprise decision-making.
Taguchi-fuzzy Theory Applied to Optimization of Teaching Module
Authors: Wu Bo-Wen , Huang Chou-Chun , Lin Wen-Chieh
Published: April 2020

In this study, a case-reference teaching method was selected, and Taguchi L9 orthogonal table combined with fuzzy control system was adopted to minimize the experimental design, maintain the high precision of the experimental data, and successfully develop the optimal analysis of teaching design mode. This model can effectively improve the quality of teaching. The research results have made a significant contribution to the optimization of teaching design, and can be replicated and followed up.
Research on Airline Route Optimization Based on Ant Colony Optimization Algorithm
Authors: Feng Shemiao
Published: April 2020

International route network planning is an important issue in airline management decision. To solve the problem, in this paper the author introduces the concept of optimal air transport route, proposes the ant colony algorithm to solve the network optimization, then the new method for this problem is presented in the paper. At last, a typical simulation study was carried out to illustrate its validity. It is founded that ACO algorithms is reliable and effective for aviation network optimization problems.
Anomaly Detection Based on Locality Sensitive Hashing with Genetic Algorithm
Authors: Zhang Tao , Fan Zijuan , Yu Xiangyu
Published: April 2020

With the increase of public safety awareness, video anomaly detection has attracted researchers’ attention. In the paper, a novel approach is proposed to detect anomalies in the video. It is based on Locality Sensitive Hashing (LSH), which maps similar data to the same bucket with high probabilities, and non-similar data is mapped to the same bucket with a low probability to detect abnormal videos that are not similar to normal videos. In order to improve the probability of similar data mapping into the same bucket, the Genetic Algorithm (GA) is used to optimize the entire hash function group while maintaining the diversity of the hash function group. The algorithm gets AUC 0.78 on the dataset UCSD ped1 and AUC 0.94 on the dataset UCSD ped2, which confirmed the effectiveness of the algorithm.
Battery Equalization Strategy for LiMn2O4 Battery Based on Fuzzy Control
Authors: Zhang Songming , Ma Xiao , Qiu Danfeng
Published: April 2020

With the pollution of the environment and the shortage of energy, new energy vehicles, especially electric vehicles (EVs), have received more and more attention. Power batteries are the most important part of new energy vehicles. Electric vehicles usually require hundreds or even thousands of batteries as the power source, but there are inconsistencies between these batteries due to manufacturing process limitations. This situation will cause over-charging and over-discharging of the batteries, which seriously affects the safety of the battery packs. In order to solve this problem, this paper proposed a battery equalization strategy based on fuzzy control, and simulated the strategy in MATLAB/SIMULINK. The result proved that the scheme could automatically balance the batteries, which effectively prevented over-charging and over-discharging of the batteries.
Permanence, Extinction and Periodic Solution of a Non-autonomous Cooperative System with Stage Structure
Authors: Halik Azhar , Muhammadhaji Ahmadjan , Mahemuti Rouzimaimaiti
Published: April 2020

This paper studies a class of non-autonomous two-species cooperative system with stage structure. Some sufficient conditions on the boundedness, permanence, extinction, periodic solution of the system are established by using the comparison method.