Al-Nahrain Journal for Engineering Sciences最新文献

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Numerical Study of Convection Air Currents Around a Hot Cylinder Inside a Triangular Cavity 三角形空腔内热圆柱周围对流气流的数值研究
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-07-08 DOI: 10.29194/njes.26020102
A. A. Mohammed, Ansam Adil Mohammed, S. Channapattana
{"title":"Numerical Study of Convection Air Currents Around a Hot Cylinder Inside a Triangular Cavity","authors":"A. A. Mohammed, Ansam Adil Mohammed, S. Channapattana","doi":"10.29194/njes.26020102","DOIUrl":"https://doi.org/10.29194/njes.26020102","url":null,"abstract":"A numerical study was performed of natural laminar convective heat transfer to its concentrated triangular enclosure around a horizontal circular cylinder. The air-filled enclosure kept the inner and outer cylinders at uniform temperatures. The Boussinesq density approximation to the momentum problem and the control volume approach iteratively resolved the governing equations to explain buoyancy. CFD results show that the velocity behavior increases by increasing Ra, so the stream lines becomes more sluggish and less uniform behavior and vortices gets less circulated pattern. The rotation angle ? has significant effect on vortices, at 90o gives the higher range of velocity zones of free convection with higher range. The thermal boundary layer seems to be larger in rr=0.455 as compared with rr=0.345 and decreases by increasing ?. The larger variation of isotherms and thermal boundary layer appears at lower ? because the higher heat transfer rate occurs at higher ? and becomes maximum at 90o. Eight correlations of average Nusselt number have been deduced as a function of Rayleigh number for the taken values of aspect ratio and enclosure angles of rotation and inclination.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79333682","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
Evaluation of Current and Post-Development Carrying Capacity of Tigris River Reach in Mayssan Province 马伊桑省底格里斯河河段承载力现状及开发后评价
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-07-08 DOI: 10.29194/njes.26020116
Maysam Qawmee Al-Naemi, Mohammed Rashid Al-Juhaishi
{"title":"Evaluation of Current and Post-Development Carrying Capacity of Tigris River Reach in Mayssan Province","authors":"Maysam Qawmee Al-Naemi, Mohammed Rashid Al-Juhaishi","doi":"10.29194/njes.26020116","DOIUrl":"https://doi.org/10.29194/njes.26020116","url":null,"abstract":"The study aims to evaluate the current flood carrying capacity and its change after some cross sections developments for the 110 km reach of Tigris River and Kmait flood escape system. This reach extends from Ali Al-Gharbi station to Amarah Barrage station. The model is calibrated by using set of data at the Ali Al-Garbi gaging station, that includes flow varied between 790 to 470 m3/s during April 2019. Manning’s n coefficient value of (0.03) is selected as it has the minimum least-squares root difference of (0.148) between the measured and estimated water levels. The results show that the current capacity of Kmait flood escape and this Tigris River reach are 280 m3/s and 1100 m3/s,  respectively.  According to the study of strategic for water and land resources in Iraq, 2014, scenarios are conducted for some cross sections development to improve the capacity of the reach to 2750 m3/s. Results of applied development show that Tigris River can safely accommodate a flood wave of 2750 m3/s when modifying the cross-sections in different locations, and raising the banks level in three locations, 0+00,  79+00 and 95+00km. Earthworks volume of development of the reach is 247603200 million m³, with the total cost of 490 billion IQD.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"98 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81145294","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
Performance Investigation of DP-16QAM Ultra-wideband- Wavelength-Division Multiplexing Communication System: Optimum Power Consideration DP-16QAM超宽带波分复用通信系统性能研究:最优功率考虑
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-03-24 DOI: 10.29194/njes.26010037
Arwa A. Moosa, R. Fyath
{"title":"Performance Investigation of DP-16QAM Ultra-wideband- Wavelength-Division Multiplexing Communication System: Optimum Power Consideration","authors":"Arwa A. Moosa, R. Fyath","doi":"10.29194/njes.26010037","DOIUrl":"https://doi.org/10.29194/njes.26010037","url":null,"abstract":"Recently, there is increasing interest in using the 18 THz bandwidth offered by S+C+L band to increase the transmission capacity of fiber communication systems. This leads to the generation of ultra-wideband (UWB) wavelength-division multiplexing (WDM) optical communication systems. In these advanced systems, stimulated Raman scattering (SRS) causes a power transfer from high-frequency channels to low-frequency channels. This effect leads to an increase in the nonlinear interference (NLI) between the UWB-WDM channels. Power optimization techniques are required to balance transfer power between band channels, thus increasing the maximum transmission reach (MTR) along with increasing system capacity. In this paper, the transmission performance of S+C+L band system operating with dual-polarization 16-QAM signaling is investigated using enhanced Gaussian noise model. The transmitter and receiver for each DP channel use a -polarized laser and incorporate two identical configurations, one for x- and the other for y-state of polarization (SOP). The results are presented for two values of symbol rate, 40 and 80 GBaud, where the system carries 360 (=160+80+120) and 180 (=80+40+60) channels, respectively. The results revel that the MTR of both cases is equal to 12 100 km-spans when the channel lunch power equals to -4 and -2 dBm, respectively. This work also shows the effect of NLI components as a function of the number of spans, channel spacing, and channel launch power. The results show that the cross-phase modulation component of the NLI has high accumulated value with transmission distance, while the self-phase modulation component is almost constant.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81654099","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: 1
Real-Time Objects Detection, Tracking, and Counting Using Image Processing Techniques 实时对象检测,跟踪,计数使用图像处理技术
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-02-20 DOI: 10.29194/njes.26010024
Mohammed H. Alhayani
{"title":"Real-Time Objects Detection, Tracking, and Counting Using Image Processing Techniques","authors":"Mohammed H. Alhayani","doi":"10.29194/njes.26010024","DOIUrl":"https://doi.org/10.29194/njes.26010024","url":null,"abstract":"As a result of the tremendous development taking place in modern systems and technologies in the field of electronic monitoring. Intelligent monitoring, decision making, and automated response systems have become common subjects at this time, especially after the development of machines responsible for these processes. Traffic surveillance is a trend goal nowadays using different techniques and equipment. In this article, real-time Object detection and tracking techniques were proposed for traffic surveillance using image processing techniques. A state was specifically examined for its ability to detect and count passing motorcycles on a highway in a specific area. The results showed good reliability, with a frame processing time of approximately about (30 ms) and the achievement of real-time performance. The main contribution of this article is reaching the best result implemented by the performance the real-time process using image process technique and tracking the object by depending on the sequencing of frames and can stands with rationally not so powerful machines. Several tools have been used for different types of necessary tasks that will be part of the required application such as Python 3.7; which was used to build the basic algorithms,Visual studio code (VSC) as an Integrated Development Environment (IDE), and Anaconda navigator for downloading many useful libraries. The specifications of the used device were Intel(R) Core (TM) i7- 10750H CPU @ 2.60GHz 2.59 GHz, RAM 16.0 GB, NVIDIA GeForce GTX 1650 GPU, 64-bit operating system, x64-based processor.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76403260","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
Design and Performance Investigation of Intensity Modulation/Direct Detection Scheme for C- and O-band Point-to-Multipoint Optical Networks C波段和o波段点对多点光网络强度调制/直接检测方案的设计与性能研究
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-02-20 DOI: 10.29194/njes.26010014
Ali Saadi, Raad Sami
{"title":"Design and Performance Investigation of Intensity Modulation/Direct Detection Scheme for C- and O-band Point-to-Multipoint Optical Networks","authors":"Ali Saadi, Raad Sami","doi":"10.29194/njes.26010014","DOIUrl":"https://doi.org/10.29194/njes.26010014","url":null,"abstract":"The fifth generation (5G) and beyond mobile networks support increasing number of users with increasing bit rate per users. This has encouraged researchers to propose coherent digital subcarrier multiplexing (SCM) point-to-multipoint (P2MP) architectures to reduce the cost and complexity of optical transport networks, particularly in the metro aggregation scenario. However, coherent optical receiver is relatively costly and complexity compared with a   direct-detection (DD) counterpart due to the use of a synchronized local laser. This paper addresses design issues and performance investigation of intensity modulation/direct-detection (IM/DD) P2MP optical networks. P2MP architectures are designed using digital RF multisubcarrier (MSC) waveform embedded on the intensity of continuous-wave (CW) laser beside direct-detection scheme. The design covers C- and O-band operation using a wavelength-division multiplexing (WDM) architecture. Further single- and double-polarization (SP and DP) versions are reported for each type of the networks. All the architectures are built in Optisystem version 15 environment and simulated for different network parameters, under the assumption of 25 Gbps per subcarrier data rate. The main performance measures are maximum route reach and bit rate-distance product (BDP). The simulation results indicate that DD networks can replaced the coherent counterpart when number of subcarriers per optical channel is 4. Further, the O-band P2MP networks offer high values of maximum reach and BDP than C-band counterparts.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83790849","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: 1
Improving the Mechanical Properties of a Composite material Reinforced with Glass Carbon for Aircraft Application 提高飞机用玻璃碳增强复合材料的力学性能
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-02-20 DOI: 10.29194/njes.26010001
K. Abed, Saad T. Faris, Iman M. Naemah
{"title":"Improving the Mechanical Properties of a Composite material Reinforced with Glass Carbon for Aircraft Application","authors":"K. Abed, Saad T. Faris, Iman M. Naemah","doi":"10.29194/njes.26010001","DOIUrl":"https://doi.org/10.29194/njes.26010001","url":null,"abstract":"  \u0000 \u0000 \u0000 \u0000 \u0000Abstract \u0000The purpose of this research is to investigate how the fiber orientation and loading axis of a composite material affect its behavior. Consideration was given to two different fiber-to-matrix ratios in order to improve the mechanical properties. Hand lay-up samples were produced in accordance with ASTM D790 for flexural testing. On UTM, tensile and flexural tests were performed on the sample. The effect of fiber orientation modifies the composites' mechanical properties. As the fiber orientation increased, the tensile strength of the composite would reduce. This carbon/epoxy composite test demonstrates better strength than those conducted at (30, 5, 60, and 90 degrees). For flexural tests, a three-point bend at 30 degrees demonstrates excellent strength. Utilizing the three-point bend method, the flexural strength and flexural modulus have been determined. The tensile strength, young's modulus, elongation percentage, maximum load to break the composite, peak load, and flexural strength of single- and double-layered carbon fibers were compared and examined. As the number of layers increased, the adhesion between layers of epoxy and fiber carbon, and glass fiber weakened, causing a decrease in almost all mechanical properties. The fabricated 2024-T3 and epoxy glass fiber had higher fatigue strength than aramid reinforced and lower density than steel alloy utilized in aircraft manufacture. \u0000 \u0000 \u0000 \u0000 \u0000 ","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89935340","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
Evaluation of Modified Asphalt Binder and Mixtures with Polyphosphoric Acid 改性沥青粘结剂及多磷酸混合料的评价
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-02-20 DOI: 10.29194/njes.26010031
M. Hilal
{"title":"Evaluation of Modified Asphalt Binder and Mixtures with Polyphosphoric Acid","authors":"M. Hilal","doi":"10.29194/njes.26010031","DOIUrl":"https://doi.org/10.29194/njes.26010031","url":null,"abstract":"Rutting is the most common distress that most Iraqi asphalt pavements suffer from it. Asphalt binders are modified by using additives and polymers to enhance their physical qualities and fulfill the performance demands. Polyphosphoric acid (PPA) has been used in many countries to enhance the physical and mechanical characteristics of asphalt binders and mixtures that can improve the performance of asphalt pavements. In this paper, evaluation of the Iraqi asphalt binder and mixtures performance by using three percentages of Polyphosphoric acid (PPA) (0.4, 0.8, and 1.2) percent by asphalt binder weight and added to (60-70) penetration grade asphalt binder to show the applicability and suitability of using PPA in asphalt pavement in Iraq. Original asphalt binder and modified are subjected to traditional tests which are penetration, ductility, softening point, and viscosity. Results show better performance and enhancement of the physical properties of the modified binder. Other tests are Marshall Stability and wheel track tests. The results of the addition of PPA to the asphalt mixture show increases in the Marshall Stability and enhance the performance of the asphalt pavement mixtures. The wheel track test is applied to the original and modified mixture at two test temperatures 40 ?C and 50 ?C and the results show a decrease in the rut depth when the percentages of PPA increase. It is concluded that %PPA addition will enhance the performance of the Iraqi asphalt pavement and the mixture will be more rutting resistant, especially in high-temperature weather.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87505730","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
Experimental Study of Mechanical Properties of Unidirectional Woven Carbon Fiber and Fiber Glass - Epoxy Composites 单向编织碳纤维与玻璃-环氧纤维复合材料力学性能的实验研究
Al-Nahrain Journal for Engineering Sciences Pub Date : 2023-02-20 DOI: 10.29194/njes.26010007
Naznaz Jalal Awla, Younis K. Khdir
{"title":"Experimental Study of Mechanical Properties of Unidirectional Woven Carbon Fiber and Fiber Glass - Epoxy Composites","authors":"Naznaz Jalal Awla, Younis K. Khdir","doi":"10.29194/njes.26010007","DOIUrl":"https://doi.org/10.29194/njes.26010007","url":null,"abstract":"In this study, the mechanical properties of an epoxy, unidirectional woven carbon and fiberglass composite were investigated experimentally. ASTM used for preparing the composite specimen. Different ranges of mixing ratios of woven carbon and fiberglass with epoxy are studied. Tensile, impact and bending test are carried out to investigate the mechanical properties for produced new composites. After testing the mechanical properties of the specimens, it is noted that adding of unidirectional woven carbon layers will leads to strengthens the samples. The mechanical properties of woven carbon composite are far superior to those of woven carbon composite with fiberglass.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88946717","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
Physical and Mechanical Properties of Cementitious PVC Composites 胶凝PVC复合材料的物理力学性能
Al-Nahrain Journal for Engineering Sciences Pub Date : 2022-12-23 DOI: 10.29194/njes.25040159
G. Jameel, Bashar Abdulazeez, Maher Mohammed, A. Al-Hadithi
{"title":"Physical and Mechanical Properties of Cementitious PVC Composites","authors":"G. Jameel, Bashar Abdulazeez, Maher Mohammed, A. Al-Hadithi","doi":"10.29194/njes.25040159","DOIUrl":"https://doi.org/10.29194/njes.25040159","url":null,"abstract":"This research studies the physical and mechanical properties of mortar composed of PVC plastic waste particles used as fine aggregate replacement material. PVC particles in quantities of 5%, 10%, 15%, 20%, 25%, and 30% by volume were used for sand fraction substitution. This quantity of PVC was used to formulate seven mixes with a cement content of 525 kg/m3 and a water-to-cement ratio (w/c) of 0.45. At 7 and 28 days, the compressive and splitting tensile strengths of the mortar's mechanical characteristics were evaluated. Additionally, the physical characteristics of density and absorption were investigated. The findings demonstrated that the mechanical properties and density of mortar containing PVC powder were minimized.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"136 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74845481","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
Data Mining for Autism Spectrum Disorder detection among Adults 成人自闭症谱系障碍检测的数据挖掘
Al-Nahrain Journal for Engineering Sciences Pub Date : 2022-12-23 DOI: 10.29194/njes.25040142
N. Al-Qazzaz, Sumaya Jaffer, Israa F. Abdulazez, Teba Yousif
{"title":"Data Mining for Autism Spectrum Disorder detection among Adults","authors":"N. Al-Qazzaz, Sumaya Jaffer, Israa F. Abdulazez, Teba Yousif","doi":"10.29194/njes.25040142","DOIUrl":"https://doi.org/10.29194/njes.25040142","url":null,"abstract":"Autism Spectrum Disorder (ASD) is one of the most common children's neurodevelopmental disorders (NDD) with an estimated global incidence of 1% to 2%. There are two aims for this research, first, to propose a data mining architecture that combines behavioural and clinical characteristics with demographic data. Second, to provide a quick, acceptable and easy way to support the ASD diagnosis. this can be performed by conducting a comparison study to determine the efficacy of four possible classifiers: logistic regression (LR), sequential minimum optimization (SMO), naïve Bayes, and instance-based technique based on k-neighbors (IBK). These classifiers have been performed with Waikato Environment for Knowledge Analysis (WEKA) tools to distinguish autistic adults from healthy, normal subjects. The results showed that, with 99.71%, SMO classification accuracy was 99.71, which exceeded the accuracy of other classifiers. The proposed architecture allows for early detection of ASD, distinguishing between ASD and healthy control subjects. This study could help doctors and clinicians by giving them a better idea of what the future holds for people with autism spectrum disorder (ASD) and by improving therapy programs, allowing people with ASD to live a long and happy life.","PeriodicalId":7470,"journal":{"name":"Al-Nahrain Journal for Engineering Sciences","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73625409","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
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