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Enhancing Power Quality with PDO-FOPID Controller in Unified Power Quality Conditioner for Grid-Connected Hybrid Renewables 利用并网混合可再生能源统一电能质量调节器中的 PDO-FOPID 控制器提高电能质量
Q4 Engineering Pub Date : 2024-02-26 DOI: 10.4314/njtd.v20i4.1805
S. Nagaraju, B. Chandramouli
Addressing the pressing research problem of power fluctuations and grid harmonics in the integration of renewable energy, our  proposed control strategy utilizes the Prairie Dog Optimization Fractional Order Proportional Integral Derivative (PDO-FOPID) controller  within a Unified Power Quality Conditioner (UPQC) system. This innovative approach is tailored to mitigate harmonics and meet load  requirements in grid-connected hybrid renewables. The UPQC system is instrumental in regulating coupling point voltage, countering  voltage and current harmonics to enhance overall power quality. The PDO-FOPID controller dynamically adapts control parameters to system dynamics and load changes, ensuring a stable power supply despite the variability of renewable sources. Simulations in MATLAB/ Simulink confirm its superiority over traditional control strategies, such as PI, sliding mode, and fuzzy control, in harmonics mitigation,  load fulfilment, and power stability. By effectively addressing these challenges, our proposed solution not only contributes to resolving a  critical research problem but also advances the seamless integration of Hybrid Renewable Energy Sources (HRES) into power systems,  thereby enhancing overall grid performance and the efficacy of renewable energy integration. 
为了解决可再生能源并网中电力波动和电网谐波这一紧迫的研究问题,我们提出的控制策略利用了统一电能质量调节器(UPQC)系统中的草原犬优化分数阶比例积分微分(PDO-FOPID)控制器。这种创新方法专为减轻谐波和满足并网混合可再生能源的负载要求而量身定制。UPQC 系统有助于调节耦合点电压,消除电压和电流谐波,从而提高整体电能质量。PDO-FOPID 控制器可根据系统动态和负载变化动态调整控制参数,确保在可再生能源变化的情况下仍能稳定供电。在 MATLAB/ Simulink 中进行的仿真证实,与 PI、滑动模式和模糊控制等传统控制策略相比,PDO-FOPID 控制器在谐波缓解、负荷满足和电力稳定性方面更具优势。通过有效应对这些挑战,我们提出的解决方案不仅有助于解决一个关键的研究问题,还能推进混合可再生能源(HRES)与电力系统的无缝集成,从而提高整体电网性能和可再生能源集成的效率。
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引用次数: 0
Morphological, Mechanical and Thermal Characteristics of PLA /Cocos nucifera L Husk and PLA/Zea mays Chaff Lignin Fibre Mats Composites 聚乳酸/椰壳和聚乳酸/玉米糠木质素纤维垫复合材料的形态、机械和热特性
Q4 Engineering Pub Date : 2024-02-26 DOI: 10.4314/njtd.v20i4.1561
O. Gbenebor, C. Odili, V.D. Obasa, E. F. Ochulor, S.O. Kusoro, O.C. Udogu-Obia, S.O. Adeosun
Polylactide (PLA) is a biodegradable polymer with low elongation which limits its use in some applications. The incorporation of biowaste  particles has been employed to improve its properties. This work thus examines the impact of lignin particles reinforced on electrospun  PLA fibre mats. Acid hydrolysis (1M of HCl at 60 and 100 oC for 2 and 4 h was used to extract lignin from Cocos nucifera L (CNHL) and Zea  Mays Chaff (CCL). Lignin particles were added to molten PLA, stirred, and electrospun at 26 kV, using a static aluminum collector plate placed at 121mm from the spinneret tip. Morphological examination reveals that fibre diameter of neat PLA (9.7 µm) increased from 107  – 285 % with the additions of reinforcements. Maximum tensile strength of 1.03 MPa is recorded for PLA/CNHL 60oC /2 h. This composite  maintains the highest elongation of 0.069 % compared to neat PLA (0.046 %). X-Ray diffractometer (XRD) result informs that the  crystallinity of neat PLA (67.6 %) improves by 3%, with the use of CNHL 60 oC/ 2 h. Thermo gravimetric analysis (TGA) result shows that  both fibre composites possess better thermal stability (380 oC) compared to reinforcing PLA fibre (319 oC).               
聚乳酸(PLA)是一种可生物降解的聚合物,其伸长率较低,这限制了它在某些应用中的使用。人们采用加入生物废料颗粒的方法来改善其性能。因此,这项研究探讨了木质素颗粒对电纺丝聚乳酸纤维毡的影响。采用酸水解法(1M 的盐酸在 60 和 100 摄氏度下水解 2 和 4 小时)从 Cocos nucifera L (CNHL) 和 Zea Mays Chaff (CCL) 中提取木质素。将木质素颗粒加入熔融聚乳酸中,搅拌并在 26 千伏电压下进行电纺,使用的静态铝收集板距喷丝板顶端 121 毫米。形态学检查显示,添加增强剂后,纯聚乳酸的纤维直径(9.7 微米)增加了 107 - 285%。与纯聚乳酸(0.046 %)相比,这种复合材料的伸长率最高,达到 0.069 %。X 射线衍射仪(XRD)结果表明,使用 CNHL 60 oC/2 h 后,纯聚乳酸的结晶度(67.6%)提高了 3%。热重分析(TGA)结果表明,与增强聚乳酸纤维(319 oC)相比,两种纤维复合材料都具有更好的热稳定性(380 oC)。
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引用次数: 0
Performance Analysis of Intelligent Computational Algorithms for Biomass Higher Heating Value Prediction 生物质高热值预测智能计算算法的性能分析
Q4 Engineering Pub Date : 2024-02-26 DOI: 10.4314/njtd.v20i4.1856
U. A. Dodo, M. A. Dodo, A.F. Shehu, Y.A. Badamasi
Higher heating value (HHV) is an essential parameter to consider when evaluating and choosing biomass substrates for combustion and  power generation. Traditionally, HHV is determined in the laboratory using an adiabatic oxygen bomb calorimeter. Meanwhile, this  approach is laborious and cost-intensive. Hence, it is essential to explore other viable options. In this study, two distinct artificial  intelligence-based techniques, namely, a support vector machine (SVM) and an artificial neural network (ANN) were employed to develop  proximate analysis-based biomass HHV prediction models. The input variables comprising ash, volatile matter, and fixed carbon were  paired to form four separate inputs to the prediction models. The overall findings showed that both the ANN and the SVM tools can guarantee accurate prediction in all the input combinations. The optimal prediction performances were observed when fixed carbon and  volatile matter were paired as the input combination. This combination showed that the ANN outperformed the SVM, having presented  the least root mean squared error of 0.0008 and the highest correlation coefficient of 0.9274. This study, therefore, concluded that the  ANN is more preferred compared to SVM for biomass HHV prediction based on the proximate analysis. 
高热值(HHV)是评估和选择用于燃烧和发电的生物质基质时需要考虑的一个基本参数。传统上,HHV 是在实验室使用绝热氧弹热量计测定的。同时,这种方法费力且成本高昂。因此,有必要探索其他可行的方案。本研究采用了两种不同的人工智能技术,即支持向量机(SVM)和人工神经网络(ANN),来开发基于近似分析的生物质 HHV 预测模型。由灰分、挥发物和固定碳组成的输入变量配对形成预测模型的四个独立输入变量。总体结果表明,ANN 和 SVM 工具都能保证对所有输入组合进行准确预测。当固定碳和挥发性物质配对作为输入组合时,预测效果最佳。这一组合显示,ANN 的表现优于 SVM,其均方根误差最小为 0.0008,相关系数最高为 0.9274。因此,本研究得出结论,在基于近似分析预测生物质 HHV 时,ANN 比 SVM 更受青睐。
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引用次数: 1
Optimal capacitor planning for power factor improvement using hybrid particle swarm and harmony search optimization 基于混合粒子群和和谐搜索优化的功率因数优化电容器规划
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1825
A. H. Ibrahim, E. C. Ashigwuike, W. Oluyombo, A. A. Sadiq
Industrial loads reduce the Power Factor (PF) of supply systems, causing increases in power losses, damaging equipment and higher utility bills. Optimization techniques are used in planning reactive sources to improve PF of power systems. However, conventional techniques suffer difficulties in passing over local optimal, divergence risk, constraints handling or computing higher order derivatives. Herein, the hybridization of Particle Swarm and Harmony Search Algorithm (PS – HSA) is developed for optimal capacitor planning to improve PF, and comparison is made with the Enhanced Particle Swarm Optimization (EPSO) and Improved Adaptive Harmony Search Algorithm (IAHSA). The test systems are the Modified IEEE 6 and 16 buses and nodes respectively. To create semblance of industrial load dominated power systems, the test networks were modified by increasing the reactive load demand at all buses of the IEEE 6 and 16 by 50% and 70% respectively. The capacitor is modelled as static shunt-controlled element deployed to inject reactive power at buses/nodes. Results show that for IEEE 6 buses, PF improved from 0.68 to 0.8983, 0.8986 and 0.8992 with EPSO, IAHSA and hybrid PS – HSA respectively. Similarly, in IEEE 16 nodes, PF improved from 0.76 to 0.9439, 0.943, and 0.944 with EPSO, IAHSA and hybrid PS – HSA respectively. Furthermore, real power losses reduced from 16.94 MW to 14.03 MW in IEEE 6 buses, translating to 17.2% reduction with the hybrid PS - HSA. While in IEEE 16 nodes, reduction is from 0.719 MW to 0.69 MW accounting for 4% reduction, also with the hybrid PS - HSA.
工业负荷降低了供电系统的功率因数(PF),导致电力损耗增加、设备损坏和水电费上涨。优化技术用于规划无功电源,以提高电力系统的功率因数。然而,传统技术在克服局部最优、发散风险、约束处理或计算高阶导数方面存在困难。在此基础上,提出了粒子群与和谐搜索算法(PS - HSA)相结合的电容优化规划方法,并与增强型粒子群优化算法(EPSO)和改进自适应和谐搜索算法(IAHSA)进行了比较。测试系统分别采用改进的ieee6和ieee16总线和节点。为了创造工业负荷主导的电力系统的外观,通过将ieee6和ieee16的所有总线的无功负载需求分别增加50%和70%,对测试网络进行了修改。电容器被建模为静态并联控制元件,部署在总线/节点注入无功功率。结果表明,对于ieee6总线,EPSO、IAHSA和混合PS - HSA分别将PF从0.68提高到0.8983、0.8986和0.8992。同样,在IEEE 16节点中,EPSO、IAHSA和混合PS - HSA的PF分别从0.76提高到0.9439、0.943和0.944。此外,IEEE 6总线的实际功率损耗从16.94 MW降低到14.03 MW,在混合PS - HSA下降低了17.2%。而在IEEE 16节点中,同样采用混合PS - HSA,从0.719 MW减少到0.69 MW,减少了4%。
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引用次数: 0
Wind resource of Ilorin City for vortex-induced wind turbine power generation and off-grid electrification 伊洛林市风力资源用于涡激风力发电和离网电气化
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1795
T. Yahaya, H. A. Ajimotokan, J. A. Adebisi, I. I. Ahmed, T. K. Ajiboye, S. Abdulkareem, K. R. Ajao
This study examined the appraisal of wind resources of Ilorin, Nigeria for vortex-induced wind turbine power generation and off-grid electrification. The technical potential of Modern-Era Retrospective Analysis for Research and Application, version 2 (MERRA-2) was employed as a tool to generate an estimated wind resource of Ilorin city, using five different hub-heights (10, 30, 50, 70, and 90 m). A statistical analysis of wind characteristics for 21 years from 2001 to 2021 was carried out using Weibull distribution function. The daytime and night-time wind characteristics were studied to determine prospective and investment hub-height(s). It was observed that the study area is a low wind region with a minimum and maximum mean wind speed of 2.89 m/s at 10 m and 7.68 m/s at 90 m, respectively. Wind turbines with cut-in wind speed of 2, 2.5, and 3 m have operational chances of 98%, 95% and 88%, respectively. Wind power density at 10, 30, and 50 m elevations was classified as poor while at 70 and 90 m elevations, was regarded as marginal and fair, respectively.
本研究考察了尼日利亚伊洛林的风力资源评价,用于涡激风力发电和离网电气化。利用《现代研究与应用回顾性分析》第2版(MERRA-2)的技术潜力,利用5个不同的枢纽高度(10、30、50、70和90 m)对伊洛林市的风资源进行估算,并利用威布尔分布函数对2001 - 2021年21年的风特征进行统计分析。研究了白天和夜间的风特征,以确定预期和投资中心的高度。研究区为低风区,10 m处最小平均风速2.89 m/s, 90 m处最大平均风速7.68 m/s。切割风速为2米、2.5米和3米的风力涡轮机的运行几率分别为98%、95%和88%。10 m、30 m和50 m海拔高度的风力密度为差,70 m和90 m海拔高度的风力密度为边际和一般。
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引用次数: 0
Mechanical characteristics and regression models of rice husk silica reinforced natural rubber composites 稻壳硅增强天然橡胶复合材料力学特性及回归模型
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1695
P. A. Ubi, N. A. Ademoh, A. S. Abdulrahman, A. B. Hassan, J. D. Dashe, S. W. Oyeyemi, F. Ngolemasango
Carbon black and silica fillers have been widely used as reinforcing fillers in tyres and engine mounts. However, both fillers are non-renewable and with REACH legislation in Europe, the USA and elsewhere, where some of these fillers are termed hazardous due to the presence of polyaromatic hydrocarbons (PAHs), there is a need to search for sustainable alternative fillers to wholly or partially replace carbon black as a filler. This research studied rice husks-derived silica (RHS) as a filler in natural rubber (NR). The characteristics of RHS at 50 phr to 90 phr filler loading levels were examined to determine its suitability as a substitute for unsustainable carbon black (N772) fillers used in the rubber industry. Bound rubber content, crosslink density, tensile strength, young modulus, tear strength, shore A hardness, compressive set, and elongation at break were measured. Regression models were generated and the correlation of determination (R2) values was obtained. The RHS composites resulted in maximum tensile strength of 13.20 MPa at 90 phr, tear strength of 119 MPa at 90 phr, shore A hardness of 69 at 90 phr, compressive set of 6.72% at 80 and 90 phr, elongation at break of 453.60% at 80 phr, bound rubber content of 92.14% at 50 phr and crosslink density of 3.87×10-2 mol/cm3 at 70 phr. The results obtained were within the range of those obtained for the carbon black filled composites across various loading levels. The R2 value of mechanical characteristics for the RHS and N772 samples respectively were 50.06% and 62.18% (bound rubber content), 97.62% and 99.85% (tensile strength), 98.44% and 63.97% (tear strength), 89.16 and 97.40% (Shore A hardness), 32.90% and 91.80% (compressive set), a d 50.91% and 46.91% (elongation at break). Rice husk-derived Silica filled natural rubber composites showed favourable mechanical properties and can substitute traditional fillers in tyres, rubber engine mounts, bushings, seals and doormats.
炭黑和二氧化硅填料被广泛用作轮胎和发动机支架的增强填料。然而,这两种填料都是不可再生的,并且随着欧洲、美国和其他地方的REACH法规,其中一些填料由于存在多芳烃(PAHs)而被称为有害的,因此需要寻找可持续的替代填料来全部或部分取代炭黑作为填料。研究了稻壳衍生二氧化硅(RHS)作为天然橡胶(NR)的填料。研究了RHS在50phr至90phr填料负荷水平下的特性,以确定其作为橡胶工业中不可持续炭黑(N772)填料的替代品的适用性。测量了粘结橡胶含量、交联密度、拉伸强度、杨氏模量、撕裂强度、邵氏硬度、压缩集和断裂伸长率。建立回归模型,得到判定值(R2)的相关性。RHS复合材料在90 phr时的最大抗拉强度为13.20 MPa,撕裂强度为119 MPa, 90 phr时的shore A硬度为69,80和90 phr时的压缩集为6.72%,80 phr时的断裂伸长率为453.60%,50 phr时的结合胶含量为92.14%,70 phr时的交联密度为3.87×10-2 mol/cm3。所得结果与炭黑填充复合材料在不同载荷水平下的结果一致。RHS和N772试样的力学特性R2值分别为50.06%和62.18%(结合胶含量)、97.62%和99.85%(抗拉强度)、98.44%和63.97%(撕裂强度)、89.16和97.40%(邵氏硬度)、32.90%和91.80%(压缩集)、50.91%和46.91%(断裂伸长率)。稻壳衍生的二氧化硅填充天然橡胶复合材料具有良好的机械性能,可以替代轮胎、橡胶发动机支架、衬套、密封件和门垫中的传统填料。
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引用次数: 0
Oil extraction from <i>Treculia africana</i> seeds: process conditions, kinetic and thermodynamic studies &lt;i&gt;非洲非洲&lt;/i&gt;种子:工艺条件、动力学和热力学研究
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1419
O. O. Okwonna, A. A. J. Obuebite, I. J. Otaraku
The declining global supply and sources of vegetable oil consumed across different parts of the world have become a source of growing concern. Finding alternative sources demands concerted efforts and studies on other agricultural products not adequately utilized. This study investigates the extraction of oil from Treculia africana seeds using n-hexane as a solvent. The effect of heat pre-treatment of the seed samples on the process was also investigated using oven-drying and sun-drying methods, respectively. The pre-treatment process had no effect on the physicochemical properties of the extract except the maximum yields at 60 min obtained as 42.5 and 40.31%, respectively. Characterization of the extract using the physicochemical properties of the oil showed specific gravity 0.931, saponification value 624.4 mgNaOHg-1oil, acid value 2.57 mgKOHg-1oil, and iodine value 14.13mg100g-1 which indicates its suitability for consumption, soap making, production of pharmaceuticals and as a lubricant. The Kinetics of the process which was studied under different temperatures and time intervals indicate a first-order reaction. Several thermodynamic parameters were determined such as activation energy, enthalpy, and entropy. These physicochemical properties indicate that the extract is comparable to the vegetable oil obtained from other sources. The kinetics and thermodynamics studies indicate the spontaneity of the process showing that the energy required to break the solute-solvent/solvent-solvent interaction was more significant than that required to maintain the bonds between them thereby favouring the forward reaction and product formation.
全球植物油供应和世界各地植物油消费来源的下降已成为人们日益关注的问题。寻找替代来源需要协调一致的努力,并对其他未得到充分利用的农产品进行研究。本研究以正己烷为溶剂,研究了从非洲treulia种子中提取油的方法。分别采用烘箱干燥法和日光干燥法研究了种子样品的热处理对该过程的影响。预处理工艺对提取液的理化性质没有影响,但60 min的最大得率分别为42.5%和40.31%。利用油的理化性质对提取液进行表征,其比重为0.931,皂化值为624.4 mgKOHg-1oil,酸值为2.57 mgKOHg-1oil,碘值为14.13mg100g-1,适合于消费、制皂、制药和润滑剂生产。在不同温度和时间间隔下的动力学研究表明,该过程为一级反应。确定了几个热力学参数,如活化能、焓和熵。这些物理化学性质表明,该提取物可与从其他来源获得的植物油相媲美。动力学和热力学研究表明,该过程的自发性表明,打破溶质-溶剂/溶剂-溶剂相互作用所需的能量比维持它们之间的键所需的能量更大,从而有利于正向反应和产物形成。
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引用次数: 0
Comparative analysis of deep learning techniques based COVID-19 impact assessment on electricity consumption in distribution network 基于深度学习技术的新冠肺炎对配电网用电量影响评估的对比分析
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1375
A. O. Amole, S. Oladipo, D. Ighravwe, K. A. Makinde, J. Ajibola
Energy is a fundamental human need for several activities. Energy can be impacted by several factors ranging from technical to social and environmental. The impact of COVID-19 outbreak on the energy sector is enormous with serious global socioeconomic disruptions affecting all economic sectors, including tourism, industry, higher education, and the electricity industry. Based on the unstructured data obtained from Eko Electricity Distribution Company this paper proposes three deep learning (DL) models namely: Long Short-Term Memory (LSTM), Simple Recurrent Neural Network (SimpleRNN), and Gated Recurrent Unit (GRU) were used to analyse the effect of COVID-19 pandemic on energy consumption and predict future energy consumption in various district in Lagos, Nigeria. The models were evaluated using the following performance metrics namely: Mean Absolute Percentage Error (MAPE), Mean Squared Error (MSE), Root Mean Squared Error (RMSE), and Mean Absolute Error (MAE). On overall, the lowest MAPE, MAE, RMSE, and MSE of 0.120, 71.073, 93.981, and 8832.466 were obtained for LSTM in Orile, SRNN in Ijora, and GRU in Ijora, respectively. Generally, the GRU performed better in predicting energy consumption in most of the districts of the case study than the LSTM and SimpleRNN. Hence, GRU model can be considered the optimal model for energy consumption prediction in the case study. The importance of having this model is that it can help the government and other stakeholders in economic planning of electricity distribution networks.
能源是人类若干活动的基本需要。能源可以受到从技术到社会和环境等几个因素的影响。COVID-19疫情对能源部门的影响是巨大的,严重的全球社会经济中断影响到所有经济部门,包括旅游业、工业、高等教育和电力行业。基于Eko配电公司的非结构化数据,本文提出了长短期记忆(LSTM)、简单递归神经网络(SimpleRNN)和门控递归单元(GRU)三种深度学习(DL)模型,分析了COVID-19大流行对尼日利亚拉各斯各区能源消耗的影响,并预测了未来的能源消耗。使用以下性能指标对模型进行评估:平均绝对百分比误差(MAPE)、均方误差(MSE)、均方根误差(RMSE)和平均绝对误差(MAE)。总体而言,Orile的LSTM、Ijora的SRNN和Ijora的GRU的MAPE、MAE、RMSE和MSE最低,分别为0.120、71.073、93.981和8832.466。总体而言,GRU在预测案例研究的大部分地区的能源消耗方面优于LSTM和SimpleRNN。因此,GRU模型可以被认为是案例研究中最优的能耗预测模型。拥有这个模型的重要性在于,它可以帮助政府和其他利益相关者进行配电网络的经济规划。
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引用次数: 0
Production of medium chain fatty acids from ensiled potato peels; effect of inoculum type and kinetic study 青贮马铃薯皮生产中链脂肪酸的研究接种类型的影响及动力学研究
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1383
J. A. Undiandeye, S. Kiman, J. V. Anaele
Medium chain fatty acids (MCFAs) are fatty acids containing 6 to 12 carbon atoms with a wide range of industrial application. They can be produced by the fermentation of waste biomass through a process called chain elongation (CE). During CE, the type of inoculum used plays a key role in determining the optimal yield of MCFAs. In this study, we showed, for the first time, the use of three different inocula including leachate, rumen fluid and digestate from a biogas reactor for the batch fermentation of ensiled potato peels for MCFAs production. Results showed that the highest chain elongation was obtained when leachate was used as inoculum with a maximum yield of 57, 4 and 26 g/kgVS for caproic acid, heptanoic acid and caprylic acid respectively. A kinetic study shows that the production of MCFAs from ensiled potato peels was better described by the first-order model than by the modified Gompertz model.
中链脂肪酸(MCFAs)是含有6至12个碳原子的脂肪酸,具有广泛的工业应用。它们可以通过称为链延伸(CE)的过程通过废弃生物质发酵产生。在CE过程中,所使用的接种物类型对mcfa的最佳产量起着关键作用。在这项研究中,我们首次展示了使用三种不同的接种剂,包括渗滤液、瘤胃液和沼气反应器中的消化液,对青贮马铃薯皮进行分批发酵,以生产MCFAs。结果表明,以渗滤液为接种剂,己酸、庚酸和辛酸的产率最高,分别为57、4和26 g/kgVS;动力学研究表明,一阶模型比改进的Gompertz模型更能描述青贮马铃薯皮产生MCFAs的过程。
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引用次数: 0
Automatic classification of breeds of dog using convolutional neural network 基于卷积神经网络的犬种自动分类
Q4 Engineering Pub Date : 2023-10-15 DOI: 10.4314/njtd.v20i3.1485
P.O. Adejumobi, I.O. Adejumobi, O.A. Adebisi, S.O. Ayanlade, I.I. Adeaga
Dog is a mammal that has been a friend of man for ages, it is naturally a domestic animal with a high level of phenotype differences in behaviour and morphology. Breeding and crossbreeding activities have increased the number of dog breeds globally, thereby resulting in dogs with inter breed similarities and intra breed differences thereby creating a difficulty in their classification. The American Kennel Club (AKC) classified breeds of dog into groups based on characteristic, purpose, behaviuor and uses in order to optimize the potentials in the breeds. However, most people find it difficult to identify and classify the dog breed groups. Existing works did not consider the automatic grouping of dog breeds. Hence, there is need for automatic techniques to classify dog breeds into groups with improved accuracy. This work used the concept of Convolutional Neural Network (CNN) to develop a model that will automatically classify dog breeds into group based on the American Kennel Club standard using the Stanford’s dog dataset. The developed model achieved 92.2% accuracy, 80.0% sensitivity, 95.3% specificity and 93.4% area under curve (AUC). The model’s performance is excellent compared to existing works that used the same dataset. The experimental result was validated with two classic CNN models (ResNet-50 and SqueezeNet) using the same parameters.
狗是一种哺乳动物,多年来一直是人类的朋友,它自然是一种家畜,在行为和形态上具有很高的表型差异。育种和杂交活动增加了全球犬种的数量,从而导致犬种间的相似性和犬种内的差异性,从而给犬种分类带来了困难。美国养犬俱乐部(AKC)根据狗的特点、用途、行为和用途将狗的品种分类,以优化品种的潜力。然而,大多数人发现很难识别和分类狗的品种群。现有的工作没有考虑犬种的自动分组。因此,有必要采用自动技术来提高犬种分类的准确性。这项工作使用卷积神经网络(CNN)的概念开发了一个模型,该模型将使用斯坦福大学的狗数据集,根据美国养犬俱乐部的标准,自动将狗的品种分类。该模型准确率为92.2%,灵敏度为80.0%,特异性为95.3%,曲线下面积(AUC)为93.4%。与使用相同数据集的现有研究相比,该模型的性能非常出色。用两个经典的CNN模型(ResNet-50和SqueezeNet)使用相同的参数对实验结果进行验证。
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引用次数: 0
期刊
Nigerian Journal of Technological Development
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