NUST Journal of Engineering Sciences最新文献_第5页

High Temperature Effectiveness of Ginger Extract as Green Inhibitor for Corrosion in Mild Steel 生姜提取物对低碳钢的高温缓蚀效果研究

NUST Journal of Engineering Sciences Pub Date : 2019-03-10 DOI: 10.24949/NJES.V11I1.266

M. Sohail, F. Hussain, A. Chandio, Maryam Sheikh

{"title":"High Temperature Effectiveness of Ginger Extract as Green Inhibitor for Corrosion in Mild Steel","authors":"M. Sohail, F. Hussain, A. Chandio, Maryam Sheikh","doi":"10.24949/NJES.V11I1.266","DOIUrl":"https://doi.org/10.24949/NJES.V11I1.266","url":null,"abstract":"Corrosion is one of the major problems of mild steels in acidic medium. This can be minimized by the application of corrosion inhibitors, however; the most of inhibitors are toxic in nature. Therefore inhibitors from green sources are highly desirable to maintain the sustainability of the environmental system. Consequently, in this study ginger was selected; its juice extracted mechanically and used as an inhibitor. The different concentrations of ginger extract such as 0.25ml, 0.5ml, 0.75ml and 1ml were mixed in 0.1 M HCl solution to record the effect of inhibitor on corrosion rate at room temperature and at an elevated temperature of 50ᵒC. Electrochemical linear polarization resistance (LPR) tests were carried out to determine the corrosion rates at both temperatures with different additions of the inhibitor respectively. The LPR test uses three electrodes, first electrode of AISI 1019 (mild steel), second electrode is standard electrode of saturated calomel while the third electrode consists of graphite, which is called counter electrode, to measure potential difference. The whole assembly was dipped in the solution having varying concentration of inhibitors. The corrosion rate was found to be higher in the absence of ginger- extract. Conversely, the corrosion rate was dramatically reduced more prominently at 50oC but was less effective at Troom; with the trace-additions of ginger-inhibitor. So this research would be the good contribution to overcome the deterioration of mild steel and increase its life at ambient temperatures, by using economically available environmentally-friendly organic compound specially the use of locally available raw material should be focused.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115039353","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: 8

Geotechnical Characteristics of Subsoil for Different Sectors of Islamabad 伊斯兰堡不同地段底土的岩土力学特征

NUST Journal of Engineering Sciences Pub Date : 2019-03-10 DOI: 10.24949/NJES.V11I1.179

M. Din, J. Ali, A. Q. Khan, F. Sami

{"title":"Geotechnical Characteristics of Subsoil for Different Sectors of Islamabad","authors":"M. Din, J. Ali, A. Q. Khan, F. Sami","doi":"10.24949/NJES.V11I1.179","DOIUrl":"https://doi.org/10.24949/NJES.V11I1.179","url":null,"abstract":"Geotechnical site investigations are essential in determining subsoil stratigraphy and soil strength and is considered mandatory for design of foundations. This study presents the generalized profiles for subsurface stratigraphy and insitu soil strength (average SPT N values) for different sectors of Islamabad on the basis of wide-ranging experimental work carried out by several agencies in fieldand laboratory testing carried out at the number of locations in the study area. Data from 208 geotechnical site investigations of Islamabad have been collected and subsurface profiling for those sectors is carried out that had more than four data points. The experimental data of the study area has shown potential for development of profile map for 11 different sectors of Islamabad using data of 144 geotechnical site investigations. Generalized soil profile and average SPT N values for each sector have been generated to a depth of 7m which is considered sufficient for lightly loaded structures with shallow foundations. Average SPT N value profile coupled with soil stratigraphy for each zone is established that can used to determine shear strength parameters and bearing capacity of soil using SPT based empirical correlations. The generalized soil profiles will be helpful during feasibility study and planning geotechnical site investigations for mega projects and can also be used to determine engineering properties of subsoil for small scale projects.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127139682","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: 3

Set point tracking of Ball and Beam System Using Genetic Algorithm based PI-PD Controller 基于PI-PD控制器遗传算法的球梁系统设定点跟踪

NUST Journal of Engineering Sciences Pub Date : 2019-03-10 DOI: 10.24949/NJES.V11I1.287

T. Ali, S. A. Malik, M. Adeel, Muhammad Amir

{"title":"Set point tracking of Ball and Beam System Using Genetic Algorithm based PI-PD Controller","authors":"T. Ali, S. A. Malik, M. Adeel, Muhammad Amir","doi":"10.24949/NJES.V11I1.287","DOIUrl":"https://doi.org/10.24949/NJES.V11I1.287","url":null,"abstract":"The ball and beam system is one of the commonly used benchmark control apparatus for evaluating numerous different real systems and control strategies. It is an inherently nonlinear and open-loop unstable system. In this paper, we have suggested an Evolutionary Algorithm (EA) based Proportional Integral-Proportional Derivative (PI-PD) controller for the set point tracking of this well-known ball and beam system. A linearized model of the ball and beam system is deduced and PI-PID control methodology is employed. The popular EA technique such as Genetic algorithm (GA) is used for tuning of the controller. The optimized values of the controller parameters are achieved by solving a fitness function using GA. The transient performance of the proposed GA based PI-PD controller (GA-PI-PD) is evaluated by carrying set point tracking analysis of the ball and beam system through MATLAB/Simulink simulations. Furthermore, the performance of GA-PI-PD controller is investigated using four different performance indices such as Integral of squared value of error (ISE), Integral of time multiplied by squared value of error (ITSE), Integral of absolute value of error (IAE) and Integral of time multiplied by absolute value of error (ITAE). The comparison of transient performance including rising time, settling time and % overshoot is made with SIMC-PID and H-infinity controllers. The comparison reveals that GA-PI-PD controller yielded transient response with small % overshoot and settling time. The superior performance of the GA-PI-PD controller has witnessed that it is highly effective for maintaining good stability and the setpoint tracking of ball and beam system with fast settling time and less overshoot than SIMC-PID and H-infinity controllers.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122481938","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: 4

Hydrodynamic and combustion behavior of low grade coals in the riser of a circulating fluidized bed combustor 低品位煤在循环流化床燃烧室提升管内的流体力学和燃烧特性

NUST Journal of Engineering Sciences Pub Date : 2019-03-10 DOI: 10.24949/NJES.V11I1.436

A. Hussain, Faraz Junejo, M. N. Qureshi, A. Haque

引用次数: 1

Parametric Statistical Significance of Iron (II) Ions Adsorption by Coconut Shell in Aqueous Solutions 椰壳吸附水溶液中铁离子的参数统计意义

NUST Journal of Engineering Sciences Pub Date : 2019-03-10 DOI: 10.24949/NJES.V11I1.285

B. Olufemi, A. Nlerum

{"title":"Parametric Statistical Significance of Iron (II) Ions Adsorption by Coconut Shell in Aqueous Solutions","authors":"B. Olufemi, A. Nlerum","doi":"10.24949/NJES.V11I1.285","DOIUrl":"https://doi.org/10.24949/NJES.V11I1.285","url":null,"abstract":"The parametric statistical adsorption of chemically unmodified coconut shell powder (CSP) to adsorb iron (II) ions from aqueous solutions was examined in this work. It was observed that the adsorption capacity increased with increasing adsorbent dose, reducing adsorbate dose, increasing contact time, decreasing temperature and reducing particle size. As observed about one gram of the adsorbent was sufficient enough to remove 98 % iron (II) ions. A total contact time of about 40 minutes was sufficient for almost complete adsorption of the ions, while a pH of about 6.0 exhibited the maximum adsorption capacity. The sorption data were fitted into Langmuir, Freundlich, Temkin and the Dubinin-Radushkevich isotherms, fitted most with the Freundlich Isotherm model. The energy values obtained from the Temkin and Dubinin-Radushkevich isotherm model indicated high chemisorption phenomenon with the adsorbents. Investigation of some kinetic models confirmed that the adsorption of iron (II) ions using CSP was a pseudo-second order kinetic process, which further corroborates that chemisorption dominates the adsorption. Fourier Transform Analysis (FTIR) further established and justified the outcome of the study. The adsorption was parametrically justified statistically with Analysis of Variance (ANOVA) and Bonferroni-Holm Posthoc significance test. Conclusively, coconut shell proved strongly to be an effective and suitable adsorbent for removing iron (II) ions from aqueous solutions.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"283 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131831975","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

On the Effect of γ-phase transformation kinetics upon microstructure response of Cold Heading Quality Steel γ-相变动力学对冷镦优质钢组织响应的影响

NUST Journal of Engineering Sciences Pub Date : 2018-12-31 DOI: 10.24949/njes.v11i2.399

S. Abro, Muhammad Sohail Hanif, Fayaz Hussain Kandhro

{"title":"On the Effect of γ-phase transformation kinetics upon microstructure response of Cold Heading Quality Steel","authors":"S. Abro, Muhammad Sohail Hanif, Fayaz Hussain Kandhro","doi":"10.24949/njes.v11i2.399","DOIUrl":"https://doi.org/10.24949/njes.v11i2.399","url":null,"abstract":"Cold heading quality CHQ steel is a versatile form over other steels as they are used non-heat treated; their strengthening mechanism is achieved through cold heading operations. Metal is therefore stretched without applying any source of heat, metal flow during the cold heading operation must depend on grains flow which increases the mechanical properties such as strength, resistance to indentation and toughness. It is therefore necessary to form the isotropic grains before applying cold heading operation may increase the properties. Gamma phase formation during the heat treatment is crucial factor for cold operation. An effort is made in this research work to study and find out the Austenite nucleation and growth morphology of commercial CHQ steel through continuous heating experiments by utilizing lead-bath up-quenching technique at differentaustenizing temperature ranges. High class Optical Microscope Olympus GX51, scanning electron microscopy techniques have been utilized to reveal and interpret the microstructure and it was found that At the 740°C, the microstructure shows the lack of homogeneity in the structure hence cold-head-ability of CHQ steel is anisotropic but at the high temperature in austenite domain at 60sec the resultant austenite is highly homogenous due to high volume fraction of austenite has been formed then the cold-head-ability properties of CHQ steel turned to be isotropic. Keywords: Up-quenching, cold heading steel, gamma transformation, heating rate etc.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"8 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114007564","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: 5

Comparative study of cut and abrasion resistance performance of gloves made from high performance composite yarns 高性能复合纱手套抗剪、耐磨性能的对比研究

NUST Journal of Engineering Sciences Pub Date : 2018-12-01 DOI: 10.24949/njes.v11i2.327

N. Akhtar, M. Malik, A. Bakkar

{"title":"Comparative study of cut and abrasion resistance performance of gloves made from high performance composite yarns","authors":"N. Akhtar, M. Malik, A. Bakkar","doi":"10.24949/njes.v11i2.327","DOIUrl":"https://doi.org/10.24949/njes.v11i2.327","url":null,"abstract":"Cut resistant gloves are generally made from different types of high performance composite yarns. To achieve a certain level of cut resistance, material type, material composition and yarn linear density are changed which however make it sometimes difficult to decide the most suitable combination of the materials. In this work, eighteen seamless gloves were made by using core and sheath friction-spun yarns of various linear densities and core types, and their cut resistance performances were compared.For this purpose, eighteen composite yarns with three linear densities i.e. 118 tex (Ne 5), 98 tex (Ne 6) and 84 tex (Ne 7) were made on a friction spinning machine by using 5.55tex (50 denier), 11.11 tex (100 denier), 16.66 tex (150 denier), 33.33 tex (300 denier) multifilament glass yarns, and 89 denier (40 micron) and 139 denier (50 micron) monofilament steel yarn as core and Kevlar®29 staple fiber as sheath. Mechanical tests of the yarns showed that the tensile strength and tenacity of yarns increased as the linear density of glass yarns increased, whereas elongation at break and time to break increased with an increase of linear density of steel monofilament yarn. Coefficient of friction of all the yarns did not show any significant trend. Abrasion and cut resistance of the gloves made from 118 tex (Ne 5) composite yarn with 5.55tex (50 denier) glass yarn as core showed the best results, whereas no significant difference was seen in the dexterity of all the gloves.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121020141","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

Potential Impact of Computational Techniques to Express the Solid Dynamics in (Gas-Liquid-Solid) Multiphase Reactors 计算技术对(气-液-固)多相反应器中固体动力学表达的潜在影响

NUST Journal of Engineering Sciences Pub Date : 2018-12-01 DOI: 10.24949/njes.v11i2.504

S. K. Suri

{"title":"Potential Impact of Computational Techniques to Express the Solid Dynamics in (Gas-Liquid-Solid) Multiphase Reactors","authors":"S. K. Suri","doi":"10.24949/njes.v11i2.504","DOIUrl":"https://doi.org/10.24949/njes.v11i2.504","url":null,"abstract":"The computational fluid dynamics codes play a paramount role by demonstrating the system dynamics. The solid dynamics in a multiphase reactor can be analysed from (Chaos, Fractures, Clustering Discrete Element and Eulerian-Langrangian) simulation methods. The Chaos analysis is studied from pressure variation and time series. It includes the characterization of the flow region and their transition. The correlation dimension from the gas phase will describe the scale behaviour in the Chaos analysis. An effective flow model with definite investigation is obtained from this analysis. The flow regimes will be characterized by the structures variation. The volume of fluid and continuum surface force models elaborate on the fluidized bed bubble dynamics in the reactor. The bubbles formation and gasification process of (Fuel gas) are studied from parameters by including (Minimum fluidization velocity, Gas surface tension, Gas viscosity and Density). The results demonstrate the parameters which are influenced by (Particle density and Size). The investigation in time series signals for the biomass gasification process will be demonstrated from the fluidized bed hydrodynamics and system basics. The solid dynamics has been investigated by indicating a novel bubbling in biomass (Wood) in the gasification process time signals. The indication of complex signals in solid dynamics can be obtained from it simultaneously.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134465214","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

A low latency quaternion-based web transmission system for augmented reality applications 增强现实应用的低延迟四元数web传输系统

NUST Journal of Engineering Sciences Pub Date : 2018-12-01 DOI: 10.24949/NJES.V11I2.405

U. Ijaz, A. D. Butt, Muhammad Husnain Khalid, Muhammad Fraz Anwar, M. Malik

{"title":"A low latency quaternion-based web transmission system for augmented reality applications","authors":"U. Ijaz, A. D. Butt, Muhammad Husnain Khalid, Muhammad Fraz Anwar, M. Malik","doi":"10.24949/NJES.V11I2.405","DOIUrl":"https://doi.org/10.24949/NJES.V11I2.405","url":null,"abstract":"This work deals with the development and testing of a low latency Animation Transmission Technology (ATT) for augmented reality applications. This web-based transmission system based on AutoBahn Pyhton web server and WebSocket LibrarY (WSLAY) integrated clients has been studied to reduce packet header size and to simultaneously allow a large number of Users to interact with each other. The transmission system in the proposed system architecture allows motion sensor’s acquisition software to easily send compressed 3D quaternion-based data from transmitter to the rendering softwares at receiver side to generate real time 3D animation on an avatar. Furthermore, effects of lossy compression of quaternion data and server limitation have also been considered. Initial simulation test results with the Python server alongside WSLAY integrated clients with virtual motion sensors have been presented in this work. It has been evaluated that the network delay (ND) has a huge improvement from more than 300 ms to less than 25 ms at 100 Hz sensor sampling rate once lossy compression of 3D quaternion data is implemented. Furthermore, the effect of motion sensor sampling frequency and broadcast server limitation on maximum number of simultaneous users/sensors is also described in this work.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132263836","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

Critical Events of Fog Attenuation Using Visibility Data in Lahore, Pakistan. 利用能见度资料分析巴基斯坦拉合尔雾衰减的关键事件。

NUST Journal of Engineering Sciences Pub Date : 2018-12-01 DOI: 10.24949/njes.v11i2.394

S. M. Yasir, M. Salman, M. Saleem

{"title":"Critical Events of Fog Attenuation Using Visibility Data in Lahore, Pakistan.","authors":"S. M. Yasir, M. Salman, M. Saleem","doi":"10.24949/njes.v11i2.394","DOIUrl":"https://doi.org/10.24949/njes.v11i2.394","url":null,"abstract":"Free-space optics (FSO) communication system is mature, unique and promising technology which is used in various countries to meet high data rate demand and last mile connectivity. FSO link has a capacity to be utilized as a primary communication links by replacing RF communication systems because of its advantages of unregulated bandwidth, broader spectrum of frequency at low power consumption. Now a days researchers has great interest in this technology because of several features and benefits of larger bandwidth, less power consumption, low installations cost, simple to install, no congestion in spectrum, secure and reliable communication without issues of right of way. In free space optical communication, environment layer is used for signal transmission which can be effected from severe weather conditions like smog, dust, smoke, rain and fog etc. In all these severe weather environments, winter fog is one of the main problem because of it offers high optical attenuation on communication link. In this investigation the entire winter season has been observed. There are four fog events which attenuate the optical signal most. Optical attenuation is estimated using three famous fog prediction models like Al Naboulsi, Kim and at wavelengths of 850nm, 1350nm, and 1550 nm. ","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114968249","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: 3