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Oxidation of Pear Seed Oil During Storage 梨籽油在贮存过程中的氧化作用
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.007
Otache Monday Abel, Amaebino Obi Philemon, Amagbor Chinelo Stella, C. Ejeomo, Enakireru Davis Bobby, Esemedafe Josephine Ufuoma
The effects of storage on the oxidative deterioration of crude Pear Seeds Oil (PSO), obtained by soxhlet extraction, were studied. Oxidation was monitored after 6 months via several analytical techniques: peroxide value, iodine value, free fatty acids, Fourier-transform infrared spectroscopy (FTIR), and Gas chromatography–mass spectrometry (GC-MS). The slow detorioration of the oil was an indication that oxidation was strongly dependent on temperature, oxygen availability and the presence of Cu2+. The mass spectra from the GC-MS results reveal the formation of secondary oxidation products, thereby denoting a transformation of primary hydroxyperoxides. This assertion is further strengthen based on the increasing value of the total Saturated Fatty Acids (SFA) from 26.09 to 29.44 % and a corresponding decrease for Unsaturated Fatty Acid (UFA) from 71.28 to 68.80 %. Other physicochemical analysis, shows that an average Iodine value recorded a reduction from 40.377 to 39.193 at a rate of 2.9 %, free fatty acid also recorded an increase at 15.18 %. Furthermore, the acid value also recorded a 2.60 % reduction. An increase in the peroxide value from 6.243 to 7.452 at a rate of 16.22 %, is a confirmation of possible formation of secondary oxidation products as revealed by the GC-MS mass spectra. Therefore the need to pay close attention during production, transportation as well as the presence of possible Cu2+ is key to addressing slow oxidation that is capable of impairing the quality of the oil.
以索氏提取法得到的梨籽油为原料,研究了贮藏条件对其氧化变质的影响。6个月后,通过几种分析技术监测氧化情况:过氧化值、碘值、游离脂肪酸、傅里叶变换红外光谱(FTIR)和气相色谱-质谱(GC-MS)。油的缓慢变形表明氧化强烈依赖于温度、氧的可用性和Cu2+的存在。质谱分析结果显示二次氧化产物的形成,表明伯羟基过氧化物的转化。饱和脂肪酸(SFA)从26.09 %增加到29.44 %,而不饱和脂肪酸(UFA)从71.28 %下降到68.80 %,进一步加强了这一论断。其他理化分析表明,平均碘值从40.377下降到39.193,下降率为2.9%,游离脂肪酸也增加了15.18%。此外,酸值也降低了2.60%。过氧化值从6.243增加到7.452,以16.22%的速率增加,证实了GC-MS质谱显示可能形成二次氧化产物。因此,在生产、运输以及可能存在的Cu2+过程中,需要密切关注,这是解决缓慢氧化的关键,因为缓慢氧化会损害油的质量。
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引用次数: 0
Forecasting Of Malaysia Gold Price with Exponential Smoothing 指数平滑法预测马来西亚黄金价格
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.005
Heidi Airisha Abdul Rahman, Muhammad Firdaus Ros Azizi, Muhammad Fahmi Saruand, Nur Amalina binti Shafie
Gold is a precious asset has attract the investors to invest. Investors has interest to know the basic knowledge about gold price and the prediction price. Prediction price will help the investors to determine the benchmark of the gold price. However, various method can be predict the price. Therefore, the objective of this study to determine the best model to forecast the Malaysia gold price. This study focus used Exponential Smoothing (ETS) forecasting models which are Single Exponential Smoothing (SES), Double Exponential Smoothing (DES), and Holt-Winters Exponential Smoothing. The best model is used to forecast the gold price in Malaysia for the next 12 months by using data from March 2016 until February 2021.The best model is determined by choosing the lowest Root Mean Squared Error (RMSE) value. The outcome for the lowest RMSE shows that DES is the best model for forecasting the gold price in Malaysia for the next 12 months. The result of the forecasting shows that the gold price will decrease from March 2021 until February 2022, and this could be due to the COVID-19 pandemic in Malaysia. Therefore, it will be a good opportunity for investors to buy gold in this period since the price is decreased and investors can sell it at the highest price in the future.
黄金是一种珍贵的资产,一直吸引着投资者进行投资。投资者有兴趣了解黄金价格的基本知识和预测价格。预测价格将帮助投资者确定黄金价格的基准。然而,各种方法可以预测价格。因此,本研究的目的是确定预测马来西亚黄金价格的最佳模型。本研究主要使用指数平滑(ETS)预测模型,即单指数平滑(SES)、双指数平滑(DES)和Holt-Winters指数平滑。最好的模型是使用2016年3月至2021年2月的数据来预测马来西亚未来12个月的黄金价格。通过选择最小的均方根误差(RMSE)值来确定最佳模型。RMSE最低的结果表明,DES是预测未来12个月马来西亚黄金价格的最佳模型。预测结果显示,从2021年3月到2022年2月,黄金价格将下跌,这可能是受马来西亚新冠肺炎疫情的影响。因此,这段时间是投资者购买黄金的好机会,因为价格下降,投资者可以在未来以最高价格出售黄金。
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引用次数: 0
Impact of Provenance on Phytochemical Attributes of Pigmented Landrace Maize Varieties 种源对有色地方玉米品种植物化学特性的影响
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.009
James Majamanda, M. Katundu, V. Ndolo, D. Tembo
Maize is one of the most diverse cereal crops that contribute highly in calorie supply to human diet. Pigmented maize secondary metabolites which are phytochemicals of healthy importance include carotenoids and phenolics which act as precursors of vitamin A and antioxidants respectively. Pigmented landrace maize is cultivated by smallholder farmers in their localities. Three different pigmented maize varieties from different growing districts were analysed for total carotenoids content (TCC) and total phenolic content (TPC), using spectrophotometer. The districts experience a warm temperate climate and higher rainfall in summer than in winter but they differ in that Ntcheu has highest average annual temperature of 20.3°C while Dedza receives the highest annual precipitation of about 1010 mm. Mzimba has an average annual temperature of 20.1°C and receives about 915 mm of precipitation annually. Individual carotenoids were analysed using high performance liquid chromatography (HPLC). TCC were significantly higher (p < 0.05) in Ntcheu and Mzimba provenances compared to Dedza. Lutein (22.84 ± 1.25 µg/g) and Zeaxanthin (23.16 ± 2.44 µg/g) were highest in landrace orange maize from Ntcheu. Mzimba provenance showed highest beta-cryptoxanthin (8.60 ± 2.15 µg/g). TPC were not significantly different between Dedza (204.29 ± 0.35 mg/Kg) and Mzimba (207.65 ± 0.22 mg /kg) red maize. Ntcheu provenance showed the least TPC (184.06 ± 0.61 mg/Kg). It seems provenance influenced phytochemical attributes of pigmented landrace maize varieties in some instances. This study also revealed that post-harvest handling of pigmented landrace maize affects phytochemical content. Care should, therefore, be taken in handling pigmented landrace maize to avoid phytochemical loses. Farmers and all other stakeholders in Malawi are encouraged to produce and include pigmented landrace maize varieties in their diets in order to gain the associated health benefits. Further studies are needed for complete characterisation of phenolic compounds of pigmented landrace maize of Malawi.
玉米是最多样化的谷类作物之一,对人类饮食的热量供应贡献很大。色素玉米次生代谢产物是具有健康重要性的植物化学物质,包括类胡萝卜素和酚类物质,它们分别作为维生素A和抗氧化剂的前体。有色地方玉米是由当地的小农种植的。采用分光光度计对不同产地的3个色素玉米品种进行了类胡萝卜素含量(TCC)和总酚含量(TPC)测定。这些地区都是温暖的温带气候,夏季降雨量比冬季多,但它们的不同之处在于,恩秋的年平均气温最高,为20.3°C,而德扎的年降雨量最高,约为1010毫米。姆辛巴的年平均气温为20.1°C,年降雨量约为915毫米。采用高效液相色谱法对单个类胡萝卜素进行分析。Ntcheu和Mzimba种源的TCC显著高于Dedza种源(p < 0.05)。其中叶黄素(22.84±1.25µg/g)和玉米黄质(23.16±2.44µg/g)含量最高。Mzimba种源β -隐黄质含量最高(8.60±2.15µg/g)。红玉米的TPC在Dedza(204.29±0.35 mg/Kg)和Mzimba(207.65±0.22 mg/Kg)之间无显著差异。Ntcheu种源TPC最低(184.06±0.61 mg/Kg)。在某些情况下,种源似乎影响了有色地方玉米品种的植物化学特性。本研究还揭示了采收后处理有色地方玉米对植物化学成分的影响。因此,在处理着色的地方品种玉米时应注意避免植物化学损失。马拉维鼓励农民和所有其他利益攸关方生产并将有色地方玉米品种纳入其饮食,以获得相关的健康益处。马拉维有色地方玉米酚类化合物的完整鉴定需要进一步的研究。
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引用次数: 1
Introduction of Ostrowski Homotopy Continuation Method for Solving Nonlinear Equations Using Mathematica 引入Ostrowski同伦延拓法求解非线性方程
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.004
Hafizudin Mohamad Nor, A. I. Asnor, Z. R. Yahya, M. Z. Ahmad
The solution to a nonlinear equation is found in this study by combining a classical and a powerful method. Basically, it is well known that the Homotopy Continuation Method (HCM) is a powerful method that has been used for solving the problem of the classical method. A new approach is introduced in this study which is known as the Ostrowski Homotopy Continuation Method (Ostrowski-HCM) with a purpose to overcome the divergence problem that arises from the classical Ostrowski’s method when a bad initial guess is used. To put it simply, when the derivative of a given function at the starting point is equal to zero, the problem arises. As a result, the division by zero renders the scheme invalid. In addition, a mathematical software, Mathematica 7.0, is used to implement the Ostrowski-HCM results. Thus, from the analysis of the results, it is proven that the Ostrowski-HCM is reliable and advantageous for solving the nonlinear equation.
本文采用经典方法和强大方法相结合的方法求解了一类非线性方程。基本上,众所周知,同伦延拓法(HCM)是一种强大的方法,已被用于解决经典方法的问题。本文提出了一种新的方法,即Ostrowski同伦延拓法(Ostrowski- hcm),以克服经典Ostrowski方法在初始猜想不准确时产生的散度问题。简单地说,当给定函数的导数在起始点等于零时,问题就出现了。因此,除零会使该方案无效。此外,利用数学软件Mathematica 7.0对Ostrowski-HCM结果进行了实现。因此,从结果的分析,证明了Ostrowski-HCM是可靠的,有利于求解非线性方程。
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引用次数: 0
Detection of Low Dose-Gamma Irradiated Spices by Photostimulated Luminescence (PSL) Technique 光激发发光(PSL)技术检测低剂量γ辐照香料
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.006
F. Shamsudin, M. Yasir
Photostimulated Luminescence (PSL) has been widely used as a rapid screening technique for the detection of various irradiated foods. This study aims to investigate the efficacy of the PSL technique in the detection of low dose-gamma irradiated spices available in the Malaysia market. Samples of clove, coriander, fenugreek, turmeric powder and curry powder were irradiated at very low doses; 0 (control), 0.2, 0.5 and 1 kGy using Cobalt-60 as a source. PSL measurements and analysis were undertaken under subdued lighting following EN 13751 methods. The PSL value in the form of photon counts (PCs/60s) of all samples as a function of the irradiation dose after 7 days of storage were determined which revealed that the PSL value increases proportionally to the radiation dose applied. The PSL also was able to discriminate between the non-irradiated (<700 PCs/60s, negative) and irradiated (>5000 PCs/60s, positive) samples after 7 days of storage. Coriander generates the highest PCs at the lowest dose (0.2 kGy) and highest dose (1 kGy) after that storage period. The PSL value of all spice samples is considered accurate and consistent at all irradiation doses. This technique is highly reliable for the detection of irradiated spices available in the Malaysia market.
光激发发光(PSL)技术作为一种快速筛选技术已被广泛应用于各种辐照食品的检测。本研究旨在调查PSL技术在马来西亚市场上检测低剂量γ辐射香料的功效。丁香、香菜、胡芦巴、姜黄粉和咖喱粉的样品受到极低剂量的辐射;0(对照),0.2,0.5和1 kGy使用钴-60作为源。PSL测量和分析在柔和照明下按照EN 13751方法进行。测定了储存7天后所有样品的光子计数(PCs/60s)的PSL值与辐照剂量的关系,结果表明,PSL值随辐照剂量的增加而成比例增加。PSL还能够在储存7天后区分未辐照(5000 PCs/60s,阳性)的样品。在最低剂量(0.2 kGy)和最高剂量(1 kGy)下,香菜产生的pc量最高。所有香料样品的PSL值在所有辐照剂量下都被认为是准确和一致的。这项技术是高度可靠的检测辐照香料可在马来西亚市场。
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引用次数: 0
Comparison of Tool Wear Mechanisms During Drilling of Aluminium Alloy 7075 in Dry and Chilled Air Conditions 7075铝合金在干燥和低温条件下钻孔时刀具磨损机理的比较
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.008
N. Mydin, A. Dahnel, Natasha A. Raof, Nor Khairushima MUHAMAD KHAIRUSSALEH, Suhaily Mokhtar
Aluminium alloys are widely used in manufacturing industry due to the need of lightweight components and low production cost. However, mechanical assembly of the alloy which requires drilling operations is challenging due to chip accumulation and heat at the cutting tool and workpiece interface. This often causes material adhesion on cutting edges, built-up edge, accelerated tool wear, shorter tool life and poor drilled hole quality. This paper investigates the effect drilling conditions (dry and chilled air at 10°C) on the wear mechanisms of tungsten carbide cutting tools during drilling Aluminium alloy 7075 (Al 7075) at two different feed rates. Chilled or cold air was used as a cooling medium in drilling Al 7075 to promote green manufacturing. Drilling operations of Al 7075 were performed at a constant cutting speed of 123 m/min with feed rates of 0.01 and 0.1 mm/rev. The cutting tools’ flank wear were measured using an optical microscope with Dino-Capture software and further examination on the tool wear (e.g., built-up edge, built-up layer, and crack) were conducted using Scanning Electron Microscopy (SEM). The results of this study indicate that at higher feed rate of 0.1 mm/rev, adhesive wear is dominant due to the presence of evident material adhesion and fractures on the cutting edges. The use of chilled air was found to cause less material adhesion, however more edge fracture occurred which could be due to workpiece hardening. Therefore, it is inferred that drilling Al 7075 with chilled air requires harder and stronger cutting tool in order prolong the tool life.
铝合金由于部件轻量化和生产成本低,在制造业中得到了广泛的应用。然而,由于切削工具和工件界面的切屑积累和热量,需要钻井作业的合金的机械装配具有挑战性。这通常会导致材料粘附在切削刃上,形成边缘,加速刀具磨损,缩短刀具寿命和钻孔质量差。本文研究了在两种不同进给速率下,钻孔条件(10℃干燥空气和10℃冷冻空气)对硬质合金刀具在钻孔7075铝合金(Al 7075)时磨损机理的影响。在a7075钻孔过程中,采用冷冻或冷空气作为冷却介质,以促进绿色制造。Al 7075以123 m/min的恒定切削速度,0.01 mm/rev和0.1 mm/rev进行钻井作业。使用光学显微镜和Dino-Capture软件测量刀具的刃口磨损,并使用扫描电子显微镜(SEM)进一步检测刀具磨损(如堆积边缘、堆积层和裂纹)。研究结果表明,在0.1 mm/rev的较高进给速率下,由于切削刃上存在明显的材料粘附和断裂,黏着磨损占主导地位。研究发现,冷却空气的使用减少了材料的粘附性,但由于工件硬化,出现了更多的边缘断裂。因此,可以推断,用冷冻空气钻削Al 7075,为了延长刀具寿命,需要更硬、更强的刀具。
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引用次数: 1
Temperature Variability Comparison Using Mann-Kendall Test 使用Mann-Kendall检验比较温度变异性
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.003
Ogunsola O.E., Dilau K.A., Ayokunnu O.D.
Climate change in terms of extreme temperature has been a global concern, and Nigeria has not been an exception. However, analysis of climatic trend comparison between the northern and southern part of Nigeria, especially in terms of temperature variability is rarely found among the available works of literature. Thus, this work therefore analyzed and compared the average temperature trends of six stations each from the far north and south of Nigeria for 30 years (1981 to 2010) using statistical analysis and the Mann-Kendall test, as a nonparametric procedure in assessing the temperature trends. However, from the results of the analysis, it was observed that at a 1% significance level, the Mann-Kendall test of the temperature trend in all the six stations considered from the south was rising significantly, while for those in the north there was no significant temperature rise in five of the six stations considered which nevertheless dropped to four stations at 5% significant level. Moreover, correlations were observed to exist only amongst stations with significant temperature trends. Hence, based on this observation, it can be concluded that the climate in the southern part of Nigeria is more prone to extreme temperature variation than that of the northern part.
极端温度方面的气候变化一直是全球关注的问题,尼日利亚也不例外。然而,对尼日利亚北部和南部的气候趋势比较的分析,特别是在温度变化方面,在现有的文献中很少发现。因此,本研究使用统计分析和Mann-Kendall检验作为评估温度趋势的非参数程序,分析和比较了尼日利亚远北和远南6个站点30年(1981年至2010年)的平均温度趋势。然而,从分析结果来看,在1%显著水平下,南方6个站点的Mann-Kendall检验的温度趋势都显著上升,而北方6个站点中有5个站点的温度趋势没有显著上升,但在5%显著水平下下降到4个站点。此外,相关性仅存在于具有显著温度趋势的台站之间。因此,根据这一观测结果,可以得出结论,尼日利亚南部的气候比北部更容易发生极端温度变化。
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引用次数: 2
Optimal Control of a Three-State Diabetic Population Model with Interventions 具有干预的三状态糖尿病人群模型的最优控制
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.002
H. Nasir
This paper studies an optimal control problem to describe the population dynamics of diabetes in the presence of intervention effects. We propose two control variables representing the interventions to reduce the incidence of diabetes, and the interventions to reduce the incidence of complications. By applying the optimal control theory, we seek to minimize the relative cost associated with the intervention efforts and to reduce the total number of people with diabetes. The solution to the optimality system is approximated by using the Forward-Backward Sweep Method. The numerical simulations show that the number of diabetics who develop complications can be reduced by adopting optimal control strategies.
本文研究了一个最优控制问题,以描述存在干预效应的糖尿病人群动态。我们提出两个控制变量,分别代表降低糖尿病发生率的干预措施和降低并发症发生率的干预措施。通过应用最优控制理论,我们寻求最小化与干预努力相关的相对成本,并减少糖尿病患者的总数。最优系统的解用正向-反向扫描法逼近。数值模拟结果表明,采用最优控制策略可以减少糖尿病患者并发症的发生。
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引用次数: 0
A Bayesian Parametric Estimation of Beta Kumaraswamy Burr Type X (Beta Kum-BX) Distribution Based on Cure Models with Covariates 基于带有协变量的Cure模型的Beta Kumaraswamy Burr型X (Beta Kum-BX)分布的贝叶斯参数估计
Q3 Multidisciplinary Pub Date : 2022-06-28 DOI: 10.30880/jst.2022.14.01.001
U. Madaki, Mohd. Rizam Abu Bakar
In statistical models for censored survival data which includes a proportion of individuals who are not subject to the event of interest under study are known as the long-term survival cured models. It has two most adopted and common models used in estimating the cure fraction namely: the mixture (standard cure) and the non-mixture models. In this research work, we introduce a Bayesian approach using the two models for survival data based on the Beta Kumaraswamy Burr Type X distribution with six parameters and compared with two existing models: beta-Weibull and beta-generalized exponential distributions in analyzing a real-life dataset. The proposed approach allows the inclusion of covariates in the model. The parameter estimation was obtained by maximum likelihood and Bayesian analysis methods. The win Bugs and MCMC pack library in R softwares were employed for the Gibbs sampling algorithm in other to obtain the posterior summaries of interest and also the trace plots by the applying of real data sets and a simulation study was done based on cure models to compare the performance of both models relating to actual sense of motivation and novelty which clarifies the usefulness of the proposed methodologies.
在剔除生存数据的统计模型中,包括一部分不受研究中感兴趣事件影响的个体,被称为长期生存治愈模型。在估计固化分数时,有两种最常用的模型,即混合模型(标准固化)和非混合模型。在本研究中,我们引入了一种贝叶斯方法,使用基于6个参数的β Kumaraswamy Burr X型分布的两种模型来分析生存数据,并与现有的两种模型(β - weibull和β -广义指数分布)进行了比较。所提出的方法允许在模型中包含协变量。采用极大似然分析和贝叶斯分析方法进行参数估计。另一方面,Gibbs抽样算法采用R软件中的win Bugs和MCMC包库,通过应用真实数据集获得兴趣的后验摘要和跟踪图,并基于cure模型进行了仿真研究,比较了两种模型在实际动机感和新颖性方面的性能,从而阐明了所提出方法的实用性。
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引用次数: 0
Microcontroller-based High-way Tunnel Electrical Controlling System 基于单片机的高速公路隧道电气控制系统
Q3 Multidisciplinary Pub Date : 2022-06-27 DOI: 10.20428/jst.v19i1.710
Asem Alhammady, Motea Alsamawi, Mokarram Aljamali, Abdullatif Alquradhi, Amin Elkustaban
High-way tunnels play an important role in our life. It’s used to solve a lot of problems such as reducing the crowds in the traffic and shortening the way from place to another. High-way tunnels have many forms like long tunnels, short tunnels and mountain tunnels. In Yemen, there are several high-way tunnels. These high-way tunnels have many problems such as repeated electricity cut off and collected water from the tunnels which result to stop vehicles to enter this tunnel. This paper suggests and implements a solution using Arduino Microcontroller to control all the electrical equipment of a highway tunnel to overcome all previous problems.
高速公路隧道在我们的生活中扮演着重要的角色。它被用来解决很多问题,比如减少交通拥挤和缩短从一个地方到另一个地方的距离。高速公路隧道有长隧道、短隧道和山地隧道等多种形式。在也门,有几条高速公路隧道。这些高速公路隧道存在着多次断电、隧道积水等问题,导致车辆无法进入隧道。本文提出并实现了一种利用Arduino单片机对高速公路隧道的所有电气设备进行控制的解决方案。
{"title":"Microcontroller-based High-way Tunnel Electrical Controlling System","authors":"Asem Alhammady, Motea Alsamawi, Mokarram Aljamali, Abdullatif Alquradhi, Amin Elkustaban","doi":"10.20428/jst.v19i1.710","DOIUrl":"https://doi.org/10.20428/jst.v19i1.710","url":null,"abstract":"High-way tunnels play an important role in our life. It’s used to solve a lot of problems such as reducing the crowds in the traffic and shortening the way from place to another. High-way tunnels have many forms like long tunnels, short tunnels and mountain tunnels. In Yemen, there are several high-way tunnels. These high-way tunnels have many problems such as repeated electricity cut off and collected water from the tunnels which result to stop vehicles to enter this tunnel. This paper suggests and implements a solution using Arduino Microcontroller to control all the electrical equipment of a highway tunnel to overcome all previous problems.","PeriodicalId":21913,"journal":{"name":"Songklanakarin Journal of Science and Technology","volume":"113 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79104317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
期刊
Songklanakarin Journal of Science and Technology
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