1,208 research outputs found

    Urban Vegetation Mapping from Aerial Imagery Using Explainable AI (XAI)

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    Urban vegetation mapping is critical in many applications, i.e., preserving biodiversity, maintaining ecological balance, and minimizing the urban heat island effect. It is still challenging to extract accurate vegetation covers from aerial imagery using traditional classification approaches, because urban vegetation categories have complex spatial structures and similar spectral properties. Deep neural networks (DNNs) have shown a significant improvement in remote sensing image classification outcomes during the last few years. These methods are promising in this domain, yet unreliable for various reasons, such as the use of irrelevant descriptor features in the building of the models and lack of quality in the labeled image. Explainable AI (XAI) can help us gain insight into these limits and, as a result, adjust the training dataset and model as needed. Thus, in this work, we explain how an explanation model called Shapley additive explanations (SHAP) can be utilized for interpreting the output of the DNN model that is designed for classifying vegetation covers. We want to not only produce high-quality vegetation maps, but also rank the input parameters and select appropriate features for classification. Therefore, we test our method on vegetation mapping from aerial imagery based on spectral and textural features. Texture features can help overcome the limitations of poor spectral resolution in aerial imagery for vegetation mapping. The model was capable of obtaining an overall accuracy (OA) of 94.44% for vegetation cover mapping. The conclusions derived from SHAP plots demonstrate the high contribution of features, such as Hue, Brightness, GLCM_Dissimilarity, GLCM_Homogeneity, and GLCM_Mean to the output of the proposed model for vegetation mapping. Therefore, the study indicates that existing vegetation mapping strategies based only on spectral characteristics are insufficient to appropriately classify vegetation covers

    Evaluation of post operative analgesic efficacy of intramuscular pethidine, compared to indometacin and diclofenac Na suppositories in unilateral inguinal hernioplasty patients

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    We compared analgesic effects of intramuscular pethidine to diclofenac sodium and indometacin suppositories. This study is a semiexperimental clinical trial study over 55 patients of 17 to 60 years old who had undergone unilateral inguinal hernioplasty. These patients divided into 3 groups incidentally the first group including 17 patients who received 100 mg indometacin suppository every 8 h to relief postoperative pain. The second group of 18 patients who received 100 mg Diclofenac Na suppository every 8 h and the third group including 20 patients who received 0.5 mg kg-1 body weight pethidine intramuscularly every 8 h and the first dose of each drug started 2 h after termination of operation. The severity of pain was checked by Visual Analogue Scale (VSA) method every 2 h for 24 h. Mean pain severity checked and compared in 6 h intervals. Mean pain severity and standard deviation in the first 24 h were 23±12 for indometacin and 27±12 for pethidine and 31±9 for diclofenac Na groups respectively. There is no meaningful difference in pain relief during the first post op day. We concluded that Indometacin and diclofenac Na suppositories are good substitutes of intramuscular pethidine to relief post op pain during the first post op day

    An Improved 24-Pulse Rectifier for Harmonic Mitigation in More Electric Aircraft

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    Abstract To increase the power rating and reduce the cost and complexity of a multi‐pulse rectifier (MPR), it is well known that the pulse number must be increased. In some practical cases, a 12‐pulse rectifier (12PR) is suggested as a good solution considering its relatively simple structure and low weight. However, 12‐pulse rectifiers cannot technically meet the standards of harmonic distortion requirements for some industrial applications, and therefore they must be used along with output filters. Two cost‐effective 24‐pulse rectifiers (24PRs) are suggested in the article, which consist of a polygon autotransformer 12PR and two pulse doubling circuits (PDCs) at dc link. The first PDC (PDC1) is based on an inter‐phase transformer (IPT) with a step‐up secondary winding, and the second one (PDC2) is based on an IPT with a step‐down secondary winding. To show the advantages of the proposed combinations compared with other solutions, simulation results are used, and also a prototype is implemented to evaluate and verify the simulation results. The simulation and experimental test results show that the total harmonic distortion (%THD) of the input current for the 12PR with PDC1 is less than 3.67%, and the 12PR with PDC2 is less than 1.45%, which meets the IEEE 519 and DO‐160G requirements. Also, it is shown that in comparison with other solutions, the proposed two configurations are cost‐effective, power factor is near unity, rating is almost 29% of the load rating, and the efficiency is almost 97.5%, which makes them a practical solution for more electric aircraft

    Comparison of knowledge, attitude and practice of Urban and rural households toward iron deficiency anemia in three provinces of Iran

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    Background: Lack of nutritional knowledge is one of the most important reasons of nutritional problems and consequently improper practice, which can lead to several complications. This study has been designed in order to compare knowledge, attitude and practices of the urban and rural households regarding iron deficiency anemia (IDA) in Boushehr, Golestan and Sistan & Balouchestan provinces in 2004. Methods: The sampling method at household's level in each province was the single-stage cluster sampling with equal size clusters. The necessary data were gathered with a structured questionnaire and via the interviews between the questioners and the eligible people in each household. Comparison of frequency of variables between urban and rural areas were tested by chi square test. Results: A total of 2306 households were selected as overall sample size. In urban areas, people recognized iron food sources better than rural areas. Knowledge level of respondents about vulnerable group for IDA and the favorite attitude of households toward IDA were better in urban areas of Sistan & Blouchestan and Golestan provinces. In Sistan & Balouchestan and Golestan, rural households who drank tea immediately before or after meal was more than urban ones. The majority of pregnant and lactating mothers (except for rural areas of Bushehr) did not take iron supplement regularly. Less than 60 percent of children used iron drop regularly. Conclusion: Knowledge, attitude, and practice levels of households toward IDA were not acceptable. One of the best ways of improving nutritional practice is nutritional education with focus on applying available food resources

    Pulse Tripling Circuit and Twelve Pulse Rectifier Combination for Sinusoidal Input Current

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    In this paper, a novel pulse tripling circuit (PTC) is suggested, to upgrade a polygon autotransformer 12-pulse rectifier (12-PR) to a 36-pulse rectifier (36-PR) with a low power rating. The kVA rating of the proposed PTC is lower compared to the conventional one (about 1.57% of load power). Simulation and experimental test results show that the total harmonic distortion (THD) of the input current of the suggested 36-PR is less than 3%, which meets the IEEE 519 requirements. Also, it is shown that in comparison with other multi-pulse rectifiers (MPR), it is cost-effective, its power factor is near unity and its rating is about 24% of the load rating. Therefore, the proposed 36-PR can be considered as a practical solution for industrial applications
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