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2021 ◽  
Author(s):  
Pankaj Singha ◽  
Swades Pal

Abstract Remote Sensing and GIS play an important role in mapping and monitoring natural resources and their management. The present study attempts to delineate wetland in the lower Tangon river basin in the Barind flood plain region using suitable water body extraction indices. The main objectives of this present study are mapping and monitoring the flood plains wetlands along with the future status of wetland areas of 2028 and 2038 using the advanced Artificial Neural Network-based Cellular Automata (ANN-CA) model. Apart from wetland area prediction, wetland depth simulation and prediction are also carried out using statistical (Adaptive Exponential Smoothing) as well as advanced machine learning algorithms such as Bagging, Random subspace, Random forest, Support vector machine, etc. for the year 2028. The result shows a remarkable change in the overall wetland area in the upcoming two decades. The small wetland patches away from the master stream are expected to dry out during the forecast period, where the major wetland patches nearer to the master stream with greater depth are rather sustainable but their depth of water may be reduced in the next decades. All models show satisfactory performance for wetland depth mapping, but the Random subspace model was identified as the best-suited depth predicting method and machine learning models explored better results that adaptive exponential smoothing. This recent study will definitely be very helpful for the policymakers for managing wetland landscape as well as the natural environment.


2021 ◽  
Vol 22 (9) ◽  
Author(s):  
Hanjar Mulya ◽  
Yanto Santosa ◽  
Iwan Hilwan

Abstract. Mulya H, Santosa Y, Hilwan I. 2021. Comparison of four species diversity indices in mangrove community. Biodiversitas 22: 3648-3655. Mangrove communities have a tidal environment that affects their species composition, which may be finite but the abundance may vary between species individuals. Many ecologists have used indices to measure species diversity without knowing the best suitable index for the community and its statistical characteristics. Therefore, this study aimed to compare species diversity indices in mangrove communities to obtain the best and most appropriate index for mangrove diversity. The comparison was done using the Simpson (1-D), Shannon, Menhinick, and Margalef indices, which were widely used and considered the best measures in various communities. The data was obtained from the field sampling using a single plot of 80×40 m2, and then it was simulated to obtain standardized variables so that the indices got the same treatment. It was calculated with descriptive statistics and species diversity indices among other Simpson, Margalef, Shannon, and Menhinick indices. Pearson correlation and UPGMA cluster were used to get conformity based on the best index criteria. The results showed the Margalef index was the best in performance that passed the assessment criteria more than Simpson (1-D), Shannon, and Menhinick index. It had a low correlation with sample variance and normality marker but had high variability of the index value. It was also sensitive to the number of species, good reduced individual sample, and good correlation with similar indices. Thus, we concluded that the Margalef index was the best index for mangrove community diversity measurement. The index was recommended for monitoring and evaluating the species diversity assessment for the mangrove community. It should not use several species diversity indices with similar meaning.


2021 ◽  
Author(s):  
Saeed Sharafi ◽  
Mehdi Mohammadi Ghaleni

Abstract Drought is one of the most complex phenomena in the world, so proper management is very important in monitoring and reducing its damage. For this purpose, Standard Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI) and Reconnaissance Drought Index (RDI) indices were used to analyze the intensity and frequency of drought in the coastal wet, mountain, semi mountain, semi desert, desert and coastal desert climates of Iran in four seasons, separately: autumn, winter, spring and summer. 43 synoptic stations with a common statistical period of 50 years (1969–2019) were selected. The results showed that the trend of drought in winter and summer is increasing in all studied climates. The highest correlation (0.80–0.99) between SPI-RDI and SPEI-RDI indices in coastal desert, mountain and semi mountain climates and the lowest correlation (0.34) between SPI-SPEI and SPEI-RDI indices in semi desert, desert and coastal desert climates were obtained. The comparison of the results in the trend analysis of the drought showed the same trend, but the SPEI index compared to the other indicators showed a quicker response to changes in drier climates. SPI-RDI variations showed similar values in colder climates. The SPEI is based on precipitation and temperature data, and it has the advantage of combining multi-scalar character with the capacity to include the effects of temperature variability in the drought assessment. Thus, SPEI is recommended as a suitable index for studying and identifying the effect of climate change on drought conditions.


2021 ◽  
Author(s):  
Nam Lyong Kang

Abstract This study examined the age-dependence of the association between diabetes and obesity among Korean adults. The data from the Seventh Korean National Health and Nutrition Examination Survey (2017) were analyzed. This paper considered the body mass index (BMI) and waist-to-height ratio (WHT2R) as obesity indices and the fasting blood glucose (FBG) as a diabetes index and used their lump mean values and the regression method. The WEHT2R was a more suitable index for examining the FBG than the BMI. The increase in the WHT2R of females was more sensitive to age than that of males. In contrast, the increase in the FBG of males was more sensitive to age than that of females. The ages that FBG increased to 100.0 mg/DL were 44.7 and 60.5 years for males and females, respectively. Korean adults should reduce their WHT2R to prevent the excessive increase in their FBG level and Korean males should take care of their FBG from a young age. The present results can be used for a preliminary inspection of diseases, such as functional degradation of Langerhans islets and gestational diabetes


Author(s):  
Taras Panskyi ◽  
Volodymyr Mosorov

A variety of clustering validation indices (CVIs) aimed at validating the results of clustering analysis and determining which clustering algorithm performs best. Different validation indices may be appropriate for different clustering algorithms or partition dissimilarity measures; however, the best suitable index to use in practice remains unknown. A single CVI is generally unable to handle the wide variability and scalability of the data and cope successfully with all the contexts. Therefore, one of the popular approaches is to use a combination of multiple CVIs and fuse their votes into the final decision. The aim of this work is to analyze the majority-based decision fusion method. Thus, the experimental work consisted of designing and implementing the NbClust majority-based decision fusion method and then evaluating the CVIs performance with different clustering algorithms and dissimilarity measures in order to discover the best validation configuration. Moreover, the author proposed to enhance the standard majority-based decision fusion method with straightforward rules for the maximum efficiency of the validation procedure. The result showed that the designed enhanced method with an invasive validation configuration could cope with almost all data sets (99%) with different experimental factors (density, dimensionality, number of clusters, etc.).


Author(s):  
Poorvi Kulshreshtha ◽  
Kishore Kumar Deepak ◽  
Raj Kumar Yadav ◽  
Didhiti Mukherjee

BACKGROUND: Fibromyalgia (FM) is associated with widespread autonomic dysfunction where sympathetic predominance explains associated complaints such as widespread pain, sleep disorders and anxiety. Recent studies indicate a possible neurovascular autonomic interaction in the pathogenesis of FM. OBJECTIVE: Our study paradigm included a modified Ewing’s battery of autonomic function tests to find the cardiac autonomic neuropathy (CAN) in FM patients. The battery comprises some tests such as the Valsalva maneuver, which are effort-dependent, so we also aimed to identify a potential simplified test out of the whole battery as an index marker of CAN in FM patients. METHODS: Forty-two female patients with FM were included in this study and were administered sympathetic and parasympathetic reactivity tests to explore the presence of CAN. We compared the results from each sympathetic and parasympathetic reactivity test against CAN. RESULTS: Delta heart rate in the deep breathing test was significantly different in patients with and without CAN. Delta heart rate also exhibited best diagnostic performance (AUC = 0.769, 95% CI: 0.619–0.920, p< 0.001), with 88% sensitivity, 64% specificity, and 89% negative predictive value (NPV). The 30: 15 ratio during the lying to standing test also emerged as a suitable index; however it did not show any difference between CAN and non-CAN patients. CONCLUSION: The delta heart rate has the best diagnostic accuracy, primarily in CAN’s exclusion by its very high sensitivity and NPV.


2021 ◽  
Vol 32 (1) ◽  
pp. 89-103
Author(s):  
Ahmad Hadri Jumaat ◽  
◽  
Suhaila Abdul Hamid ◽  

Abundance and distribution of aquatic insects respecting to several water chemical parameters from six rivers were studied in order to determine the performance of biological index in monitoring the water quality. A total of 960 individuals of aquatic insects from nine orders were recorded using kick and drag sampling techniques. Lubok Semilang had the greatest number of aquatic insects with 250 individuals, followed by Telaga Tujuh (181 individuals) and Sungai Durian Perangin (171 individuals). EPT (Ephemeroptera, Plecoptera and Trichoptera) order were the most dominant order recorded in all six rivers. Lata Kekabu had more diverse and richer aquatic insect assemblages based on ecological indices compared to the other five rivers. In order to evaluate the water quality of recreational rivers in Malaysia, Family Biotic Index (FBI), Malaysian Family Biotic Index (MFBI) and Biological Monitoring Working Party (BMWP) were used and compared with Water Quality Index to determine the water quality at the study areas. Results demonstrated that the biotic indices were more sensitive towards changes in water parameters than the WQI. Among all the biological indices, MFBI was the most suitable index to be adopted in Malaysian river water assessment as it is more reliable in assessing the status of water quality.


2021 ◽  
Vol 2 (1) ◽  
pp. 47-63
Author(s):  
Ansgar Scherp ◽  
Till Blume

Indexing the Web of Data offers many opportunities, in particular, to find and explore data sources. One major design decision when indexing the Web of Data is to find a suitable index model, i.e., how to index and summarize data. Various efforts have been conducted to develop specific index models for a given task. With each index model designed, implemented, and evaluated independently, it remains difficult to judge whether an approach generalizes well to another task, set of queries, or dataset. In this work, we empirically evaluate six representative index models with unique feature combinations. Among them is a new index model incorporating inferencing over RDFS and \texttt{owl:sameAs}. We implement all index models for the first time into a single, stream-based framework. We evaluate variations of the index models considering sub-graphs of size $0$, $1$, and $2$ hops on two large, real-world datasets. We evaluate the quality of the indices regarding the compression ratio, summarization ratio, and F1-score denoting the approximation quality of the stream-based index computation. The experiments reveal huge variations in compression ratio, summarization ratio, and approximation quality for different index models, queries, and datasets. However, we observe meaningful correlations in the results that help to determine the right index model for a given task, type of query, and dataset.


Author(s):  
Ting Ai ◽  
Omri Gillath ◽  
Gery C. Karantzas

According to attachment theory, security providing attachment figures fulfill two main functions: (1) safe haven—providing safety and comfort and reducing stress—helping people regain a sense of security; and (2) secure base—providing resources and a base from which people can spring into action. According to the Dual Function of Security Priming Model, security priming can result in one of two outcomes paralleling these two functions. Which outcome is likely to present itself depends on the level of stress imposed by the context. Here we describe the Dual Function Model of Security Priming (DFSP) Model and provide evidence from a study examining the effects of attachment security priming on hypothalamic-pituitary-adrenal activity. In the study, participants were exposed to security-related cues under high or low/no-stress conditions, while their salivary cortisol concentrations were measured. Cortisol is a suitable index as it is released not only in response to stress, but also more generally when energy needs to be mobilized. We found that while security priming led to significant decreases in salivary cortisol concentrations when presented after a stressor (stress reduction), it led to a significant increase in salivary cortisol concentrations when presented before the stressor (energy mobilization).


Author(s):  
Long Dinh Hoang Nguyen ◽  
Dao Nguyen Khoi

An Giang Province is one of the key economic regions of Mekong Delta and of Vietnam. With the development of urbanization and industrialization, An Giang has been suffering a burden from natural disasters, including salinity intrusion, drought, and riverbank erosion, due to natural and anthropological drivers. Amongst them, riverbank erosion is a key problem of the An Giang province, caused by changes in hydrological and sediment characteristics because of hydropower development and sand exploitation in the upstream part. In this study, we investigated the riverbank changes by using the water extraction index based on the Landsat imagery data. Amongst three extraction indices, such as Normalized Difference Water Index (NDWI), Modified Normalized Water Index (MNDWI), and Automated Water Extraction Index (AWEI), AWEI was identified the suitable index for the study area replied on the assessment of the index performance in extracting the riverbank in the four test sites in An Giang province (An Phu District, Vinh Hoa District, Cho Moi District, and Vam Nao River). Based on that, AWEI was then used for riverbank extraction for the study area in the period 1989-2015. After using the AWEI riverbank extracting method, Linear Regression Rate (LRR) had been applied to estimate the rate of the riverbank changes in the study area. The results stated that the rate of riverbank erosion was high in meandering river segments and upper part of islets, such as Tan Chau (-33m/year), Cho Moi (-36m/year) and Vam Nao (-3.07m/year). Besides analyzing the rate of erosion, this research also discusses some potential reasons as well as protection method to mitigate this problem. This study reveals that it is crucial to take sustainable measures to mitigate erosion in An Giang province.


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