Soil erosion is a global problem that has been exacerbated in recent decades by global warming an... more Soil erosion is a global problem that has been exacerbated in recent decades by global warming and the increased frequency of extreme weather events. It is also a global issue addressed by the United Nations’ Sustainable Development Goal #15 that seeks to recover degraded land and create a world free of land degradation by 2030. In this study, we used the Unit Stream Power-based Erosion Deposition (USPED) model to investigate the distribution of soil erosion and deposition in an important reservoir watershed in Taiwan, which is known to have a high risk of sediment hazard. We found the average soil erosion rate to be 136.4 Mg/ha/year using the model’s recommended m = 1.3 and n = 1.2 empirical coefficients for a combined occurrence of sheet and rill erosion. Additionally, we selected the Sule sub-watershed and the Kala area as examples to illustrate the pattern of soil erosion and deposition and their relationship to rivers, roadways, and anthropogenic activity, and 3D terrain was em...
Soil erosion is a global environmental challenge that the United Nations Sustainable Development ... more Soil erosion is a global environmental challenge that the United Nations Sustainable Development Goal (UN SDG) #15 wants to address, and the topographic factor, according to the RUSLE (Revised Universal Soil Loss Equation) model, is one of the most critical factors causing soil erosion. In this study, we employed three separate digital elevation models of Taiwan, with horizontal resolution ranging from 20 to 90 m, to compute the LS factors based on the upslope contributing areas and multiple flow directions, utilizing the methodologies used by the European Soil Data Centre. This is the first study to create a map of Taiwan’s island-wide LS factors without using a fixed slope length of 40 m. To compare European Union countries with Taiwan, we also calculated their LS means, standard deviations, and coefficients of variation of LS factors. As a result, Taiwan’s high LS values are readily noticeable as compared to the EU. Taiwan’s LS factor is greater than that of any EU country and th...
ISPRS International Journal of Geo-Information, 2021
Soil erosion is a form of land degradation. It is the process of moving surface soil with the act... more Soil erosion is a form of land degradation. It is the process of moving surface soil with the action of external forces such as wind or water. Tillage also causes soil erosion. As outlined by the United Nations Sustainable Development Goal (UN SDG) #15, it is a global challenge to “combat desertification, and halt and reverse land degradation and halt biodiversity loss.” In order to advance this goal, we studied and modeled the soil erosion depth of a typical watershed in Taiwan using 26 morphometric factors derived from a digital elevation model (DEM) and 10 environmental factors. Feature selection was performed using the Boruta algorithm to determine 15 factors with confirmed importance and one tentative factor. Then, machine learning models, including the random forest (RF) and gradient boosting machine (GBM), were used to create prediction models validated by erosion pin measurements. The results show that GBM, coupled with 15 important factors (confirmed), achieved the best res...
Letter to the editor regarding Bhattacharya et al. (2020). Sub-basin prioritization for assessment of soil erosion susceptibility in Kangsabati, a plateau basin: A comparison between MCDM and SWAT models
ISPRS International Journal of Geo-Information, 2021
The universal soil loss equation (USLE) is a widely used empirical model for estimating soil loss... more The universal soil loss equation (USLE) is a widely used empirical model for estimating soil loss. Among the USLE model factors, the cover management factor (C-factor) is a critical factor that substantially impacts the estimation result. Assigning C-factor values according to a land-use/land-cover (LULC) map from field surveys is a typical traditional approach. However, this approach may have limitations caused by the difficulty and cost in conducting field surveys and updating the LULC map regularly, thus significantly affecting the feasibility of multi-temporal analysis of soil erosion. To address this issue, this study uses data mining to build a random forest (RF) model between eight geospatial factors and the C-factor for the Shihmen Reservoir watershed in northern Taiwan for multi-temporal estimation of soil loss. The eight geospatial factors were collected or derived from remotely sensed images taken in 2004, a digital elevation model, and related digital maps. Due to the me...
Nowadays, the storage capacity of a reservoir reduced by sediment deposition is a concern of many... more Nowadays, the storage capacity of a reservoir reduced by sediment deposition is a concern of many countries in the world. Therefore, understanding the soil erosion and transportation process is a significant matter, which helps to manage and prevent sediments entering the reservoir. The main objective of this study is to examine the sediments reaching the outlet of a basin by empirical sediment delivery ratio (SDR) equations and the gross soil erosion. The Shihmen reservoir watershed is used as the study area. Because steep terrain is a characteristic feature of the study area, two SDR models that depend on the slope of the mainstream channel and the relief-length ratio of the watershed are chosen. It is found that the Maner (1958) model, which uses the relief-length ratio, is the better model of the two. We believe that this empirical research improves our understanding of the sediment delivery process occurring in the study area.
This study continues a previous study with further analysis of watershed-scale erosion pin measur... more This study continues a previous study with further analysis of watershed-scale erosion pin measurements. Three machine learning (ML) algorithms—Support Vector Machine (SVM), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Artificial Neural Network (ANN)—were used to analyze depth of erosion of a watershed (Shihmen reservoir) in northern Taiwan. In addition to three previously used statistical indexes (Mean Absolute Error, Root Mean Square of Error, and R-squared), Nash–Sutcliffe Efficiency (NSE) was calculated to compare the predictive performances of the three models. To see if there was a statistical difference between the three models, the Wilcoxon signed-rank test was used. The research utilized 14 environmental attributes as the input predictors of the ML algorithms. They are distance to river, distance to road, type of slope, sub-watershed, slope direction, elevation, slope class, rainfall, epoch, lithology, and the amount of organic content, clay, sand, and silt in the soi...
Tropical watersheds in Taiwan and Thailand face the same severe soil erosion problem that is incr... more Tropical watersheds in Taiwan and Thailand face the same severe soil erosion problem that is increasing at an alarming rate. In order to evaluate the severity of soil erosion, we quantitatively investigate the issue using a common soil erosion model (Universal Soil Loss Equation, USLE) on the Shihmen reservoir watershed of Taiwan and the Lam Phra Ploeng basin of Thailand, and compare their respective erosion factors. The results show an interesting contrast between the two watersheds. Some of the factors (rainfall factor, slope-steepness factor) are higher in the Shihmen reservoir watershed, while others (soil erodibility factor, cover and management factor) are higher in the Lam Phra Ploeng basin. The net result is that these factors cancel each other out, and the amount of soil erosion of the two watersheds are very similar at 68.03 t/ha/yr and 67.57 t/ha/yr, respectively.
Shihmen Reservoir watershed is vital to the water supply in Northern Taiwan but the reservoir has... more Shihmen Reservoir watershed is vital to the water supply in Northern Taiwan but the reservoir has been heavily impacted by sedimentation and soil erosion since 1964. The purpose of this study was to explore the capability of machine learning algorithms, such as decision tree and random forest, to predict soil erosion (sheet and rill erosion) depths in the Shihmen reservoir watershed. The accuracy of the models was evaluated using the RMSE (Root Mean Squared Error), MAE (Mean Absolute Error), and R2. Moreover, the models were verified against the multiple regression analysis, which is commonly used in statistical analysis. The predictors of these models were 14 environmental factors which influence soil erosion, whereas the target was 550 erosion pins installed at 55 locations (on 55 slopes) and monitored over a period of approximately three years. The data sets for the models were separated into 70% for the training data and 30% for the testing data, using the simple random sampling...
SummaryRabies is an invariably fatal, but preventable zoonotic disease. Despite a national progra... more SummaryRabies is an invariably fatal, but preventable zoonotic disease. Despite a national programme for its prevention and control, the number of rabies associated deaths in Vietnam has increased in recent years. A cross‐sectional survey was undertaken in 2012 to assess and compare the knowledge, awareness and practices of 189 public health workers (PHW) and animal health workers (AHW) attending a joint training course for professionals from provinces in northern Vietnam with the highest number of deaths from rabies. Questionnaires facilitating self‐evaluation were provided, and total knowledge scores were calculated (maximum 38 points) and categorized into: ‘high’ (>30 points), ‘moderate’ (21–30) and ‘low’ (<21). The response rate was 100%, and among the 189 participants, 56% were PHW compared to 44% who were AHW. Although most respondents knew rabies could be transmitted through the bite of an animal, most commonly a dog, and that rabies is a preventable disease, significan...
P atient 1. A 48-year-old male construction worker, with no preceding medical illnesses, was admi... more P atient 1. A 48-year-old male construction worker, with no preceding medical illnesses, was admitted to the intensive care unit of a hospital in Hanoi. For a few days prior to admission he experienced pain and numbness in both forearms and a flushed sensation throughout his body. He also reported increased perspiration and increased libido. At presentation, the patient was lucid but markedly agitated, and was unable to swallow due to involuntary inspiratory muscle spasms when he was presented with a glass of water (Video S1) or when he felt a breeze. On examination he was afebrile, and had a dry mouth, normal heart rate and blood pressure, and a Glasgow Coma Score of 15. He had no focal neurological signs and no neck stiffness, and Kernig's sign was negative. Neither the patient nor his wife recalled that he had been bitten by a dog, cat, bat, or other mammal in the preceding months, and his skin showed no evidence of recent bite injuries or cuts. Patient 2. A 37-year-old male farmer, without any prior medical history, presented himself to a Hanoi outpatient clinic with increased perspiration, intermittent muscle spasms of both legs, and the inability to drink normally due to involuntary inspiratory muscle spasms when he was presented with a glass of water or felt a breeze. Disease onset was several days before admission. On examination, the patient had a normal body temperature, heart rate, and blood pressure, and a Glasgow Coma Score of 15. The patient was lucid with periods of agitation. There were no focal neurological signs and no neck stiffness, and Kernig's sign was negative. He had bilateral pupil dilatation (~5 mm) with weak direct and consensual light reflexes. There were no signs of recent bites or other skin injuries, but the patient reported that he had been bitten in the heel by a pet dog one month prior to presentation. The dog had remained healthy since the bite. The families of the patients in this manuscript have given written informed consent to publication of their case details.
O52 Méta-analyse de stratégies interventionnelles et non médicamenteuses dans le diabète de type 1 de l’enfant et l’adolescent
Diabetes & Metabolism, 2011
Objectif Estimer l'efficacite de strategies interventionnelles et non pharmacologiques sur l&... more Objectif Estimer l'efficacite de strategies interventionnelles et non pharmacologiques sur l'equilibre diabetique. Materiels et methodes La recherche bibliographique a utilise les bases de donnees Medline et Embase de 1966 a Fevrier 2010 et 1974 a Juin 2007, respectivement. Les meta-analyses deja publiees ont ete incluses et les references des articles selectionnes ont ete etudiees. Il n'y a pas eu de restriction de langue. Les criteres de selection etaient : essais cliniques randomises chez des enfants et adolescents ; un des criteres de jugement devait etre l'hemoglobine glyquee (HbA1c). La selection des articles et l'extraction des donnees ont ete realisees par deux auteurs independants. La collecte des donnees et l'analyse statistique ont ete realisees avec le logiciel Easyma. Resultats La recherche bibliographique a permis d'identifier, 152 articles et 7 meta-analyses deja publiees. Apres lecture des articles, 43 ont ete retenus et regroupes en 6 types de prise en charge. D'autres evenements cliniques comme, une hypoglycemie severe, une acidocetose, la variation du poids ont ete releves. Dans la meta-analyse sur les interventions educationnelles, il y a une amelioration de l'HbA1c de − 0,8% [− 1,2 ; − 0,3] (p = 0,0000). Il existe aussi un effet benefique de la prise en charge psychologique : taille de l'effet − 0,23 [− 0,4 ; 0,2] (p = 0,01). Concernant la prise en charge au debut du diabete, un seul essai remplissait les criteres de selection. Pour les systemes de controle des parametres biologiques et la telemedecine, il n'y a pas d'effet statistiquement significatif, meme si on releve une tendance a l'amelioration de l'HbA1c. Il n'est pas possible de conclure sur l'effet des mesures hygieno-dietetiques. Conclusion Il y a un effet statistiquement benefique des mesures educationnelles et psychologiques sur l'equilibre du diabete de type 1 chez l'enfant et l'adolescent. Concernant les autres strategies interventionnelles, il semblerait que ces mesures soient benefiques, mais il faudrait des essais cliniques plus puissants pour les evaluer.
Objectives. The aim of this study was to systematically evaluate adverse drug reactions (ADRs) in... more Objectives. The aim of this study was to systematically evaluate adverse drug reactions (ADRs) in children consulting at the pediatric emergency unit during a 6-month period. Method. The regional pharmacovigilance center (CRPV) and the department of clinical pharmacology prospectively and systematically recorded all potential ADRs among patients younger than 18 years of age in the pediatric emergency unit reported at the daily staff meetings. All cases were then screened and validated by the CRPV. For validated cases, preventability, seriousness, and offlabel use were evaluated. Results. During the study period, from 1 March to 1 September 2005, 90 children presented potential adverse drug events. ADRs were confirmed in 43 patients, 19 females and 24 males. Thirty-four patients (79%) were under the age of 5. According to the European definition, 14 patients (33%) had serious ADRs. One anaphylactic shock after amoxicillin injection; antimalarial prophylaxis misuse leading to convulsive status epilepticus, convulsion, and coma after hepatitis B and MMR vaccines were deemed life-threatening. Three ADRs were considered avoidable. Antibiotics and vaccines were the most common possible cause of ADRs (76%). Skin reactions (n = 27), fever (n = 8), and gastric disorders (n = 5) were the most common clinical manifestations. Conclusions. Because ADRs were reported by clinicians on a voluntary basis, serious ADRs were probably reported more syste
PM2.5 Forecasting Using LSTM Sequence to Sequence Model in Taichung City
Lecture notes in electrical engineering, Dec 19, 2019
Accuracy and speed are crucial in the machine learning forecasting. Specifically, when encounteri... more Accuracy and speed are crucial in the machine learning forecasting. Specifically, when encountering high variance segments like sequence forecasting case. For example, air quality data has various time-series variables such as temperature, CO, rainfall, wind speed, O3, SO2, and many more. To predict such as the PM2.5 which based on various parameters needs state of the art methods on a combination of forecasting models and machine learning methods. The Long Short Term Memory Networks (LSTM) autoencoders are capable of handling with a sequence of input. In this case, the predictive modeling problems involving sequence to sequence prediction problems called seq2seq network. In this paper, a sequence forecasting model is proposed for the air quality in Taichung City Taiwan, that is consist of five areas, Xitun, Chungming, Fengyuan, Dali, and Shalu. Statistic correlation analysis was implemented to find better accuracy and speed. A comparison of before and after using statistic correlation analysis in the LSTM seq2seq modeling is provided to examine the accuracy, speed, and variance score.
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