Engineer-Journal of the Institution of Engineers Sri Lanka最新文献_第9页

Evaluation of PERSIANN-CCS Satellite Derived Rainfall Product with Raingauge Data over Kelani River Basin, Sri Lanka 基于斯里兰卡Kelani河流域雨量资料的PERSIANN-CCS卫星衍生降雨产品评价

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2022-06-10 DOI: 10.4038/engineer.v55i1.7481

B. Basnayake, U. G. C. R. Madushani

{"title":"Evaluation of PERSIANN-CCS Satellite Derived Rainfall Product with Raingauge Data over Kelani River Basin, Sri Lanka","authors":"B. Basnayake, U. G. C. R. Madushani","doi":"10.4038/engineer.v55i1.7481","DOIUrl":"https://doi.org/10.4038/engineer.v55i1.7481","url":null,"abstract":"Satellite rainfall estimates (SREs) are high in spatial and temporal resolution and particularly important for regions with sparse raingauges. However, SREs are required to evaluate with gauged rainfall data before applying for hydrological studies. In this research, the accuracy of Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks Cloud Classification System (PERSIANN-CCS) product was evaluated at daily, monthly, yearly, and seasonal scale upon the raingauge data of the Kelani River basin of Sri Lanka for the period 2004 to 2010. The performance of the SREs was evaluated using both continuous and categorical verification statistics. PERSIANN-CCS rainfall estimates follow the bi-modal rainfall pattern and showed greater underestimation in South West Monsoon (SWM) season (May-Sep.) and overestimation in InterMonsoon 1 (IM1) period (March-April). PERSIANN-CCS is more capable of recognizing conventional and depressional rains than monsoonal rains. On the other hand, it produces low false alarms in the high rainy season than in the low rainy season. The daily categorical statistics show above average scores (Accuracy>0.69; POD>0.65; FAR<0.34; 0.76>FBias<1.11), however, estimations were with low CC (<0.53) and high bias (<24 & >-64%). Bias corrected PERSIANN-CCS may be a high-resolution rainfall source for flood forecasting applications in the Kelani River basin.","PeriodicalId":42812,"journal":{"name":"Engineer-Journal of the Institution of Engineers Sri Lanka","volume":"254 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73367269","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

Gap Acceptance of Crossing Pedestrians at Unprotected Mid-Block Crosswalks in Urban Divided Highways 城市分道公路无防护中间街区人行横道过路行人间隙验收

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2022-06-10 DOI: 10.4038/engineer.v55i1.7487

V. Wickramasinghe, D. G. V. C. Diddeniya, K. G. M. Lakmali

引用次数: 0

Passive Mechanical Characterization of Human Skeletal Muscle Rectus Femoris of Sri Lankan Test Subjects 斯里兰卡被试人体骨骼肌股直肌的被动力学特性

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2022-06-10 DOI: 10.4038/engineer.v55i1.7492

A. Abeygunawardane, E. Edirisinghe, A. Karunarathne, H. T. D. W. Ariyarathne, P. Dissanayake, S. Yasawardene

引用次数: 0

Hydrological Modelling with the Tank Model for Water Resource Management of Nilwala River Basin 基于槽模型的尼尔瓦拉河流域水资源管理水文模拟

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2022-06-10 DOI: 10.4038/engineer.v55i1.7489

M. Wickramarachchi, N. Wijesekera

引用次数: 0

Prioritization of Sub-basins of Nilwala River Basin for Flood Exposure using Multi Criteria Decision Analysis 基于多准则决策分析的尼尔瓦拉河流域洪水灾害优先排序

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2022-06-10 DOI: 10.4038/engineer.v55i1.7483

B. Basnayake

{"title":"Prioritization of Sub-basins of Nilwala River Basin for Flood Exposure using Multi Criteria Decision Analysis","authors":"B. Basnayake","doi":"10.4038/engineer.v55i1.7483","DOIUrl":"https://doi.org/10.4038/engineer.v55i1.7483","url":null,"abstract":"Morphometric analysis is useful to investigate flood proneness of a river basin. Prioritization of a river basin using relevant morphometric parameters and other causative parameters can be performed using Multi Criteria Decision Analysis (MCDA) method. Nilwala river basin is subjected to flooding every year. The aims of this research were to evaluate the morphometric parameters to understand the hydrological behaviour of the Nilwala river basin and to apply Technique of Order of Preference Similarity to the Ideal Solution (TOPSIS) for prioritizing its sub basins for flood exposure. This study considered morphometric parameters, climatic, geologic, and land use factors as causative factors for flooding. Geographic Information System of Environmental Systems Research Institute (ArcGIS) was used to extract parameters using Digital Elevation Model (DEM) of Shuttle Radar Terrain Mission (SRTM), soil map, and land use map of the river basin. TOPSIS was adopted for ranking the sub basins based on the causative factors. The Nilwala river basin was classified into three relative flood exposure zones as high, moderate, and low. The study indicated that analysis of morphometric parameters provides an intuitive information on sub basin characteristics related to flooding. Results showed that 20%, 54%, and 26% of the basin area have high, moderate, and low flood exposure, respectively. High and moderate flood exposure zones are mainly located along the main river course.","PeriodicalId":42812,"journal":{"name":"Engineer-Journal of the Institution of Engineers Sri Lanka","volume":"117 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76114848","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

Start-Up Time of Crossing Pedestrians with Different Signal Configurations 不同信号配置下行人的启动时间

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2021-12-30 DOI: 10.4038/engineer.v54i4.7475

V. Wickramasinghe, P. Wijesinghe, K. G. M. Lakmali

{"title":"Start-Up Time of Crossing Pedestrians with Different Signal Configurations","authors":"V. Wickramasinghe, P. Wijesinghe, K. G. M. Lakmali","doi":"10.4038/engineer.v54i4.7475","DOIUrl":"https://doi.org/10.4038/engineer.v54i4.7475","url":null,"abstract":": Pedestrian start-up time is a very important factor when designing the pedestrian signal phase at a pedestrian crosswalk. Start-up time is divided into two categories as early start-up and delayed star-up time. If a pedestrian starts to move from the curb during the red light, it is termed as early start-up time whereas if the pedestrian starts moving from the curb after the green light, then it is termed as delayed start-up time. Pedestrian crossing time is the summation of the start-up time of the pedestrian and the time required to cross the road. By adding this start-up time into the pedestrian signal phase can reduce the interaction between pedestrians and vehicles, and excess delay at pedestrian crossings. From the initial study, it was observed that start-up time is greatly influenced by the signal configuration. Thus, this research has the intention of assessing the effect of different signal configurations into the pedestrians’ start-up time based on pedestrian characteristics, and thereby, find the best signal configurations with minimum start-up delay. Data was obtained from the video footages from three different pedestrian crossings; (1) Traditional red and green phase, (2) Countdown with waiting time phase, (3) Countdown without waiting time phase. One-way ANOVA statical test was used to evaluate whether there exists any significant deference between these signal configurations. Further, Post-Hoc (Tukey) test was conducted to evaluate which specific signal configuration differs significantly from each other. Finally, a multiple linear regression model was developed by considering start-up time as dependent variable and pedestrian characteristics and signal configurations as independent variables. The model was validated with a R value of 0.75 and pedestrian characteristics such as age, gender, having a bag, and the signal configurations are highly significant to the start-up time in the proposed regression model.","PeriodicalId":42812,"journal":{"name":"Engineer-Journal of the Institution of Engineers Sri Lanka","volume":"1 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85295346","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

Comparative Study of the Wind Codes: An Application to Forty-Six Storied Wall-Frame Structure 46层框架-剪力墙结构的风规范比较研究

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2021-12-30 DOI: 10.4038/engineer.v54i4.7469

B. Kiriparan, J. Jayasinghe, U. I. Dissanayake

{"title":"Comparative Study of the Wind Codes: An Application to Forty-Six Storied Wall-Frame Structure","authors":"B. Kiriparan, J. Jayasinghe, U. I. Dissanayake","doi":"10.4038/engineer.v54i4.7469","DOIUrl":"https://doi.org/10.4038/engineer.v54i4.7469","url":null,"abstract":": Wind is a random movement of air particles in both time and space, which produces very complicated dynamic loading scenario on flexible structures like tall buildings. Modern tall buildings are becoming more slender, flexible, lightweight and irregular in shape due to revolution of associated technologies. Consequently, analysis of tall buildings considering complicated nature of wind loading and dynamic response of the structural system is an important role in design of tall buildings. Wind tunnel test is the most reliable tool for the estimation of dynamic wind loading on tall buildings. However, due to the cost and time involved, wind design codes are generally used during the preliminary design stage. Thus, understanding the background of dynamic wind loading and procedures adopted in wind design standards to represent the dynamic effects is vital to arrive at an efficient, safe and economical structural system during the preliminary design stage. This paper presents an overview on background of dynamic wind loadings and provisions of four international wind codes frequently referred to in Sri Lanka, British Standard (BS), European Standard (BS EN), Australian Standard (AS/NZS) and Standard of Architectural Institute of Japan (AIJ). Further, the concept of equivalent static load derived based on the “gust-factor” method adopted in most of the international wind design codes is discussed. At the end, a forty-six storied wall-frame structure was used as the numerical example for the explanation of dynamic wind loading and its influence on the structural design.","PeriodicalId":42812,"journal":{"name":"Engineer-Journal of the Institution of Engineers Sri Lanka","volume":"228 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89197911","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

Application of Augmented Reality for Distance Learning to Teach Manufacturing Engineering during COVID-19 Social Distancing COVID-19社交距离期间增强现实远程学习在制造工程教学中的应用

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2021-12-30 DOI: 10.4038/engineer.v54i4.7476

Yoshika Alahakoon, A. Kulatunga

{"title":"Application of Augmented Reality for Distance Learning to Teach Manufacturing Engineering during COVID-19 Social Distancing","authors":"Yoshika Alahakoon, A. Kulatunga","doi":"10.4038/engineer.v54i4.7476","DOIUrl":"https://doi.org/10.4038/engineer.v54i4.7476","url":null,"abstract":"The COVID-19 pandemic has created a shift in all our lives, turning in-class traditional educational systems into distance learning systems. Since distance learning is inevitable nowadays, the hands-on experience from in-class, particularly in practical sessions, is lacking. While there is a wide range of tools and technologies to enrich the student learning experience, the application of Augmented Reality (AR) is remarkable. This paper proposes a mobile app assisted with AR technology aimed to support the engineering faculty students to enhance their knowledge regarding the lathe machine and lathe operations during this pandemic period. The application consists of the augmented content of the separate parts of the lathe machine, exploded view and augmented animated content of the operations. The objective of this AR app is to guide the students regarding machineries and operations, and to introduce AR technologies to the local universities as a step of enhancing digital education. The adaptability of the AR app was experienced and verified by 72 students and the responses and feedback revealed their interest towards this educational approach. Conclusively, this study shows the effectiveness and importance of AR application specially for Manufacturing Engineering field during this distance learning period.","PeriodicalId":42812,"journal":{"name":"Engineer-Journal of the Institution of Engineers Sri Lanka","volume":"32 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88685524","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

Development of a Methodology for Activity Pattern Representation for Individuals in Western Province of Sri Lanka 斯里兰卡西部省个人活动模式表示方法的发展

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2021-12-30 DOI: 10.4038/engineer.v54i4.7473

P. Fernando, G. D. De Silva

引用次数: 0

Defect Detection in Woven Fabrics by Analysis of Co-occurrence Texture Features as a Function of Gray-level Quantization and Window Size 基于灰度量化和窗口大小函数的机织物共现纹理特征分析

IF 0.3

Engineer-Journal of the Institution of Engineers Sri Lanka Pub Date : 2021-12-30 DOI: 10.4038/engineer.v54i4.7470

P. S. H. Pallemulla, S. Sooriyaarachchi, C. R. De Silva, C. Gamage

{"title":"Defect Detection in Woven Fabrics by Analysis of Co-occurrence Texture Features as a Function of Gray-level Quantization and Window Size","authors":"P. S. H. Pallemulla, S. Sooriyaarachchi, C. R. De Silva, C. Gamage","doi":"10.4038/engineer.v54i4.7470","DOIUrl":"https://doi.org/10.4038/engineer.v54i4.7470","url":null,"abstract":"In this experimental research, the effects of gray-level quantization and tiling window size on 22 gray-level co-occurrence matrix features were investigated in the context of automated woven fabric defect detection. A dataset comprising 1426 128×128 images was used, in which defective and the defect-free images were split in a 50:50 ratio. Experiments were carried out with seven quantization levels (LL = 4, 8, 16, 32, 64, 128 and 256) and four window sizes (NN = 8, 16, 32, 64). The features were extracted from each image in the training set for each< LL,NN >combination and thereafter were ranked using the joint mutual information metric. Next, for each < LL,NN > combination, a k-nearest neighbour classifier was trained, first with only the highest-ranking feature and thereafter iteratively by adding features of lower ranks. It was observed that a minimum of nine features were needed to achieve an acceptable (>90%) F1 score for any < LL,NN >combination, except when NN is relatively large. The two features that contribute to improving the F1 score for any < LL,NN >combination were found to be Homogeneity I and Homogeneity II. It was also noted that using an 8×8 window on images with 128 gray levels resulted in a practically usable high F1 score (96.39%) with the least number of features (14).","PeriodicalId":42812,"journal":{"name":"Engineer-Journal of the Institution of Engineers Sri Lanka","volume":"16 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89801550","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: 2