NUST Journal of Engineering Sciences最新文献

{"title":"Drinking water quality monitoring of centralized water storage reservoirs in various zones of the National University","authors":"Aiza Javed, H. Amjad, I. Hashmi","doi":"10.24949/njes.v15i2.721","DOIUrl":"https://doi.org/10.24949/njes.v15i2.721","url":null,"abstract":"Physico-chemical and microbiological pollutants may compromise quality of drinking water. This study aims to highlight various physico-chemical and microbial parameters of drinking water samples from centralized water storage reservoirs of National University. Major water quality parameters which were examined in this study includes pH, Electrical conductivity (EC), Turbidity, Total suspended solids (TSS), Total dissolved solids (TDS), Dissolved oxygen (DO), Residual chlorine, Hardness, Alkalinity. Moreover, microbial analysis of water samples was also carried out through Most Probable Number technique (MPN). Results show that all the physico-chemical parameters were within prescribed limits of World Health Organization and Pakistan Drinking Water Quality Standards (WHO/PDWQS) in both underground and overhead water storage reservoirs except DO ( 9.05-9.2 and 9.05-9.1 mg/L ), TSS (10-20 and 3.3-10 mg/L) and residual chlorine (0.08-0.14 and 0.19-0.28 mg/L) respectively. The MPN index values for both underground and overhead water storage reservoirs ranges between 16- >23 and 1.1-12 respectively and it shows  high microbial contamination in water due to low detection of residual chlorine. The results highlight that water from centralized water storage reservoirs of National University is unfit for drinking purposes. Statistical analysis such as paired t-test also reveals that water quality parameters from underground and overhead storage reservoirs are not significantly different from each other except EC and TDS having P values <0.05. It is necessary to safeguard water contamination in water storage reservoirs by monitoring regular inspections and chemical cleaning of water storage reservoirs otherwise it will cause serious threats to well-being of the community. \u0000Key words: water storage reservoirs, drinking water, microbial quality of water, physico-chemical parameters, paired t-test","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134464289","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}

{"title":"Optimization of TIG Welding Parameters for Ti-6Al-4V Titanium Alloy using the Taguchi Design of Experiment","authors":"A. Sattar, Azhar Hussain, M. Abbas, Muhammad Nadeem Azam, K. Mehmood, A. Wakeel, Sarim Ali","doi":"10.24949/njes.v15i2.731","DOIUrl":"https://doi.org/10.24949/njes.v15i2.731","url":null,"abstract":"This paper presents the effect of tungsten inert gas welding parameters (i.e. welding current, welding speed and filler wire speed) on weld bead geometry, notch tensile strength (NTS) and weld bead hardness of 2.0 mm thick annealed Ti6Al4V titanium alloy sheet welded in a square butt joint configuration using Taguchi L9 (33)   three level - three factor matrix.  Taguchi’s signal to noise ratios was calculated to obtain optimum welding parameters for Vickers hardness at weld area, Notch tensile strength (NTS), Front bead width (FBW) and Front reinforcement height (FRH). Analysis of Variance (ANOVA) was conducted to find statistically significant and insignificant factors with respect to each response. It was noted that welding speed has significant effect on weld hardness, notch tensile strength, front bead width and height. Optimum parameters for hardness were found to be 120A current, 400 mm / min welding speed and 250mm/min filler wire speed. Confirmation test using the optimal levels of welding parameters was also conducted in order to compare predicted results with values obtained through experimentation.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126389529","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}

{"title":"Denial of Service (DoS) Defences against Adversarial Attacks in IoT Smart Home Networks using Machine Learning Methods","authors":"Z. Iqbal, Azhar Imran, Amanullah Yasin, Adnan Alvi","doi":"10.24949/njes.v15i1.677","DOIUrl":"https://doi.org/10.24949/njes.v15i1.677","url":null,"abstract":"The availability of information and its integrity and confidentiality are important factors in information and communication of the system security. The DDoS attack generally means Distributed denial of services generates many enormous packets to slow and down the Services for actual users who use services. The study examines the impact of a considerable rise in the number of connected devices in the IoT concept on the quantity and volume of DDoS attacks. Thanks to machine learning-based technology, intrusion Detection Systems (IDS) can be versatile and efficient. However, the advancement of machine learning systems, alongside the application of the uses for Adversarial Machine Learning, has also introduced a new potential attack vector; machine learning models which support the uses of the IDS’ decisions may be subject to cyberattacks known as Adversarial Machine Learning (AML). AML is widely applicable to manipulating data and network traffic that transverse networked devices in the IoT setting. However, harmful network packets are frequently misclassified as benign perturbations in the machine learning classifier’s decision bounds. Because of this, machine learning-based detectors such as malware scanners skip those flaws and reduce the risk of delaying detection and spreading malicious code, and incurring issues such as personal information leaking, damaged hardware, and financial loss. Furthermore, this research investigates which DoS attack techniques should be implemented and how adversary samples should be constructed to strengthen the robustness of supervised models utilizing adversarial training. The system obtained 99.98% accuracy with XGBoost and 99.96% accuracy achieved with the decision tree and AdaBoost.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127270629","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}

{"title":"Experimental Investigation of Concrete Properties using Locally available Coarse Aggregates in Punjab, Pakistan","authors":"M. Khan, M. Shah, Muhammad Usman","doi":"10.24949/njes.v15i1.655","DOIUrl":"https://doi.org/10.24949/njes.v15i1.655","url":null,"abstract":"Concrete is the most widely used construction material worldwide. The concrete mainly consists of cement, water, fine aggregate(FA), and coarse aggregate(CA).CA is the main constituent of concrete in terms of weight and volume. The properties of CA can affect the fresh and mechanical properties of concrete. In the present study, CA from three different sources (Sargodha, Mangla, and Margalla) are used in three different mixes of grade M-20 (1:1.5:3) concrete. The FA aggregate source (Chenab) is kept the same in all three mixes with constant w/c=0.5. It is observed that the fresh properties of concrete with Margalla and Sargodha CA are better compared to the  Mangla source aggregate. This is because the CA of both the sources is relatively smooth in shape compared to the Mangla source that improves the flowability of concrete. While the lesser flowability of the Mangla source concrete is due to CA used is flaky, elongated, and has high absorption. The mixes with Margalla and Sargodha aggregate also performed slightly better in terms of mechanical properties. But overall, a significant difference occurred in the fresh properties of mixes compared to mechanical properties. Hence, it can be said that in normal strength concrete the different sources of aggregate mainly affect the fresh properties of concrete.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132388669","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}

{"title":"To Study the Structural, Optical and Magnetic Properties of Ni-Fe Doped ZnO Diluted Magnetic Semiconductors","authors":"Abdul Rehman, N. Rizvi, Muhammad Tahir Khan","doi":"10.24949/njes.v15i1.678","DOIUrl":"https://doi.org/10.24949/njes.v15i1.678","url":null,"abstract":"The iron and Nickel co-doped in zinc oxide nano-particle, Zn1-x-yFexNiyO {(x=0, y=0), (x=0.05, y=0), (x=0, y=0.05), (x=0.03, y=0.02)} were prepared by Sol-Gel technique. This type of synthesis is used for the manufacture of a Field Effect Transistor (FET) detector which is extremely sensitive, secure, and capable of reproducing. It is also used for the detection of the Piperidine (CH2)5NH (hexahydro pyridone) chemical. \u0000The well-closed pack spherical nano-particles of the identified crystalline structure of the usual wurtzite hexagonal phase were achieved by characterization of X-Ray Diffraction (XRD). The blue shift was well observed of Co-doped samples as compared to un-doped or single-doped ZnO nanoparticle samples by UV-visible absorption spectrum. The Fourier Transform Infrared Spectroscopy (FTIR) reveals the existence of chemical bonding and functional groups are established and the occurrence of iron Fe in modes associated with iron Fe in addition to ZnO.  The room temperature ferromagnetism was achieved in single or co-doped (Fe-Ni) with ZnO nanoparticles and is confirmed by magnetic characterization (VSM). It was perceived that magnetic saturation was improved in Fe-Ni Co-doped samples relative to pure or single doped. Also, the characterizations of samples show that the exchange interaction of Ni and Fe dominates over Ni-Ni and Fe-Fe interactions.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127433798","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}

{"title":"Evaluation and Performance of SM2-Satellite Precipitation Product with Reference to Ground-Based Observations, in different cities of Pakistan","authors":"Asif Ali, H. Farid","doi":"10.24949/njes.v15i1.675","DOIUrl":"https://doi.org/10.24949/njes.v15i1.675","url":null,"abstract":"Rainfall is the fundamental component to drive globalized hydrological cycle. Satellite-based precipitation having great inherency over land with wider range of applications, but their validation is at risk due to lack of rain gauge observations in different regions of the world. All precipitation product community are used to monitor the substitute data of rainfall in water resources, climatology, hydrology, meteorology, and geography. This research paper calculated the performance of SM2 precipitation product on different region, climate, elevation, and rainfall rate. For investigation, the ten statistical metrics and three categorical statistic have been analyzed at 11 station over 12 years period from 2007 to 2018. The different statistical technique assessed the analysis of precipitation product at different temporal scales (monthly, seasonally, and yearly) to investigate performance score. On the monthly and yearly time scales, product was less reliable with low correlation (0.0057 to 0.67) vary with elevation but best correlation (0.81) and linear regression coefficient (1.02) was calculated at seasonal scale than rest scales. The rainfall captured rate at seasonal scale with (>80%) was more than another scale. The outcome of this product from satellite community is less at monthly scale with significantly under and overestimation and with BIAS (-34.08% to 132.45%) than seasonal and yearly scale. But slightly over and underestimation pattern exist at seasonal scale with BIAS score (5.13% to -19.61%). During winter, research product reduces its systematic bias, NMAE and NRMSE and maintains its potential at also another seasons. The impact of elevation and different rainfall events are also investigated to detect the performance of SM2 satellite. More intense precipitation was captured by SPPs SM2 with high score of POD (> 0.70 to 0.99) vary with respect to more elevation area. The elevation trend increasing gradually from south (near mean sea level) to the northwest (northern areas of Pakistan) that having complex topography with intense rainfall rate. Same interpolated pattern of precipitation were assessed from south to northern areas of Pakistan like elevation using Arc GIS software. The overall evaluated results shows that precipitation product can detect heavy precipitation events easily than less intense events at monthly and yearly scale but reliable to capture at seasonal scale. This SPP is not completely reliable for low precipitation event with high altitude.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133536506","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}

{"title":"Delineation and Evaluation of Groundwater Quality by using GIS mapping system and Statistical Approaches in Southern Punjab, Pakistan","authors":"Asif Ali, A. Shakoor","doi":"10.24949/njes.v15i1.666","DOIUrl":"https://doi.org/10.24949/njes.v15i1.666","url":null,"abstract":"                The groundwater is the second largest source of water in Pakistan. This study deals with the delineation and evaluation of spatial variations in the groundwater quality in Multan, Khanewal, Lodhran, Vehari, Pakpattan and Sahiwal district of Southern Punjab, Pakistan. The three major indicators such as EC, SAR and RSC (Electrical Conductivity, Residual Sodium Carbonate and Sodium Adsorption Ratio) are used and appraisal for irrigation to check groundwater quality via GIS, GS+ software and statistical analysis. The groundwater samples were evaluated for its applicability in irrigation and for mapping consequence . The parameters analyzed were compared with Standards that were adopted by WAPDA, PID and PCRWR. Kriging interpolation maps were delineated with three zone layers such as good (weight = 3), marginal (weight = 2) and bad (weight = 1). It was concluded that the area under marginal and hazardous groundwater quality with low weights was significantly increased from 2 to 10% and 7 to 40% in pre- and post-monsoon respectively due to EC, SAR and RSC parameters. Most of the study area (> 35%) contaminated was due to EC parameters. Most of the study area (tehsil Kabirwala) was observed with low quality against all discussed quality parameters in both season. The groundwater quality parameter weightage decreases from northeast to southwest of study region. Low weightage zones were observed in lower part of the area. It is recommended that in high vulnerability area artificial well recovery, auriferous storage and rain harvesting techniques should be adopted specially in lower part to reduce salinity of water. The policy maker should make policies about regulation of water resources with good quality for best utilization of water for agricultural and industrial use.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"317 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133231029","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}

{"title":"Parametric Investigation of Gas Condensate Mobility versus Permeability in Multiphase Flow Reservoirs","authors":"Irshad Ali Gopang, A. H. Tunio, Sarfaraz Ahmed Jokhio","doi":"10.24949/njes.v14i2.668","DOIUrl":"https://doi.org/10.24949/njes.v14i2.668","url":null,"abstract":"The characterization of the gas condensate reservoir is complicated due to the multiphase flow of the fluid. The change of the composition of the excellent stream further makes it complicated. Such characterization is being done to measure the superb performance. To overcome this complexity, rigorous mathematical modelling is suggested for well test analysis. This mathematical modelling can be used to establish the correlation between well test analysis and well performance analysis. The research work is carried out to develop the analytical method to calculate the effective permeability of the gas condensate reservoir, gas condensate mobility and effects of mobility on the effective permeability. Here the different mathematical models are studied during the research work. The other correlations are used to determine the reservoir fluid's properties. Perrine’s method is used to estimate reservoir permeability. The research was carried out to analyze the effects of gas condensate mobility on permeability. In this work, the pressure build-up test data is analyzed, effective permeability ( ), gas condensate mobility and effects of gas condensate mobility are analyzed. This study found effective permeability and mobility by applying mathematical models, oil 14.603 mD, gas 0.148 mD and water 17.159 mD. Using the data obtained through the correlations, the calculated mobility (λ) of the oil, gas and water phase is 126.652 mD/cp, 13.454 mD/cp and 98.671 mD/cp, respectively.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125433310","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}

{"title":"Experimental Modal Analysis of Angle Signals Based on the Stochastic Subspace Identification Method","authors":"In-Ho Kim","doi":"10.24949/njes.v14i2.672","DOIUrl":"https://doi.org/10.24949/njes.v14i2.672","url":null,"abstract":"This paper aims to verify the extraction of modal parameters from angle signals using the stochastic subspace identification (SSI) method. The use of angle signal-based mode shapes can reduce the loss of node information and enhance the robustness in curva-ture-based damage detection. In this regard, the system identification of angle signals should be first conducted prior to the damage detection. For large structures, an out-put-only system identification method should be considered for the modal analysis of an-gle signals, because artificial shaking excitation or impact excitation is practically impos-sible. In order to achieve this, the SSI method is used; it is one of the most powerful tools among the output-only system identification methods because it does not cover nonlinear problems. In order to demonstrate the system identification process of angle signals using the SSI method, the transformation matrix is assumed to represent the relationship be-tween the angular displacement and the normal displacement. Next, the modified block Hankel matrix that consists of angle signals, which can be expressed as a multiplication between the transformation matrix and displacement series vector, is constructed. The observability matrix can be estimated using the singular value decomposition for the pro-jection of the future part onto the past part of the modified block Hankel matrix. Finally, the natural frequencies and angle signal-based mode shapes are calculated using the state and observation matrices. In order to verify the results of the analytical studies, the modal properties estimated from the numerical simulation and the SSI method using angu-lar-velocity measurements are compared.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131037484","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}

{"title":"Synergy Estimation Method for Simultaneous Activation of Multiple DOFs Using Surface EMG Signals","authors":"Rabya Bahadur, Saeed ur Rehman, G. Rasool, Muhammad AU Khan","doi":"10.24949/njes.v14i2.661","DOIUrl":"https://doi.org/10.24949/njes.v14i2.661","url":null,"abstract":"Surface electromyography signals are routinely used for designing prosthetic control systems. The concept of synergy estimation for muscle control interpretation is being explored extensively. Synergies estimated for a single active degree of freedom (DoF) are found to be uncorrelated and provide better results when used for single movement classification; however, an increase of simultaneously active DoFs leads to complex limb movements and multiple DoF detection becomes a challenge. Synergy estimation is a non-convex optimization technique, to provide better estimation this paper proposes the use of regularized non-negative matrix factorization for the evaluation of synergistic weights in complex movements. The use of regularization constraint makes the overall problem bounded and provide smoothness. The proposed technique showed better accuracy when tested for activation of multiple DoF simultaneously at a significantly lower computational time, i.e., by 34%.","PeriodicalId":338631,"journal":{"name":"NUST Journal of Engineering Sciences","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117311147","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}