Zonal Patterns of Meteorological Drought on the Yunnan-Guizhou Plateau, China

Drought is a natural phenomenon caused by a shortage of water resources and has a great impact on agriculture, the economy, and the environment. To study the Spatio-temporal distribution and explore the zonal patterns of drought, this paper took the Yunnan-Guizhou Plateau (YGP) as the research region, selected the air temperature, relative humidity, sunshine duration, wind speed, and precipitation data from 47 meteorological stations on the YGP. First, the standardized precipitation evapotranspiration index (SPEI) was calculated, and then the Spatio-temporal distribution of YGP drought was analyzed with the SPEI, Mann–Kendall test, and principal component analysis (PCA). Finally, the correlations between the average SPEI, drought characteristics extracted from the SPEI, and longitude/elevation/latitude were analyzed with the linear regression method, and then the zonal patterns of the YGP drought were obtained. The results revealed that the annual and seasonal SPEI values mainly decreased. Because the first component of the SPEI (the largest eigenvalue makes it the most important component) in annual and winter had a poor relationship with longitude/elevation, its correlation was weak, while the average SPEI values in other seasons were significantly correlated with longitude/elevation (α = 0.001), and the absolute value of the correlation coefficient was between 0.6879–0.9453. Except for PC1 in annual and winter, PC1 and PC2 were significantly correlated with longitude/elevation (α = 0.001), and the absolute value of the correlation coefficient was between 0.5087–0.9501. The duration, severity, intensity, frequency of drought were significantly correlated with longitude/elevation (α = 0.001) in most situations. The average SPEI values and drought characteristics showed a good multivariate linear correlation with longitude, latitude, and elevation, indicating that drought exhibited strong zonal patterns. This study will provide new ideas for drought research and technical support for regional industrial layouts, planting structure adjustments, and drought and disaster reduction.

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Simultaneous Measurement of Ear Canal Movement, Electromyography of the Masseter Muscle and Occlusal Force for Earphone-Type Occlusal Force Estimation Device Development

Sensors ◽

10.3390/s19153441 ◽

2019 ◽

Vol 19 (15) ◽

pp. 3441

Author(s):

Kurosawa ◽

Taniguchi ◽

Momose ◽

Sakaguchi ◽

Kamijo ◽

...

Keyword(s):

Correlation Coefficient ◽

Masseter Muscle ◽

Partial Correlation ◽

Force Estimation ◽

Ear Canal ◽

Basic Study ◽

Occlusal Force ◽

Absolute Value ◽

The Absolute ◽

Partial Correlation Coefficient

We intend to develop earphone-type wearable devices to measure occlusal force by measuring ear canal movement using an ear sensor that we developed. The proposed device can measure occlusal force during eating. In this work, we simultaneously measured the ear canal movement (ear sensor value), the surface electromyography (EMG) of the masseter muscle and the occlusal force six times from five subjects as a basic study toward occlusal force meter development. Using the results, we investigated the correlation coefficient between the ear sensor value and the occlusal force, and the partial correlation coefficient between ear sensor values. Additionally, we investigated the average of the partial correlation coefficient and the absolute value of the average for each subject. The absolute value results indicated strong correlation, with correlation coefficients exceeding 0.9514 for all subjects. The subjects showed a lowest partial correlation coefficient of 0.6161 and a highest value of 0.8286. This was also indicative of correlation. We then estimated the occlusal force via a single regression analysis for each subject. Evaluation of the proposed method via the cross-validation method indicated that the root-mean-square error when comparing actual values with estimates for the five subjects ranged from 0.0338 to 0.0969.

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Spatio-temporal distribution of zooplankton and physico-chemical conditions of Wasai Reservior, Kano State, Nigeria

Bayero Journal of Pure and Applied Sciences ◽

10.4314/bajopas.v12i1.30s ◽

2020 ◽

Vol 12 (1) ◽

pp. 186-192

Author(s):

I.H. Isyaku ◽

S. Ibrahim

Keyword(s):

Correlation Coefficient ◽

Pearson Correlation ◽

Oxygen Demand ◽

Temporal Distribution ◽

Mean Value ◽

Strong Positive Correlation ◽

Chemical Parameters ◽

Wet Season ◽

Physico Chemical ◽

Spatio Temporal

A study of spatio-temporal distribution of zooplanktonic community in relation to physico-chemical water condition of Wasai Reservoir was carried out between March and October, 2018. Three sampling sites selected for the purpose of this study were based on different human activities taking place in the areas like fishing, sand collection, washing etc. Nine physico-chemical and biological parameters were determined on fortnight basis 8:00 to 10:00am using standard methods. The result revealed that temperature, pH, Electrical conductivity, Total dissolved solids, Dissolved oxygen, Biochemical oxygen demand, transparency, nitrate and phosphate ranged from 24.4 to 29.1°C, 6.4 to 8.4, 353.3 to 846.6µS/cm, 264.3 to 602.8mg/L, 6.7 to 10.9mg/L, 2.8 to6.8mg/L, 5.6 to 12.3cm, 0.12 to 0.55mg/L and 0.08 to 0.22mg/L respectively. A total of thirteen (13) species of zooplankton were identified from the reservoir out of which three (3) belong to the class copepoda with a highest mean value of 37.67 recorded in May and lowest, 8.88 in October. Five species belong to the class Rotifera with a highest mean of 2.93 recorded in March and lowest in June (0.80). Similarly five species belong to the class Cladocera, with highest mean of 3.40 in April and lowest (0.27) in June and October respectively. The result showed seasonal variation in zooplankton species, as thier distribution increased in the dry season than in wet season, primarily due to the increase in photic depth of the water. Pearson correlation coefficient was used to determine the relationship between zooplankton and physico-chemical parameters. The correlation coefficient of physico-chemical parameters and zooplankton of the reservoir revealed strong positive correlation between zooplankton, EC, TDS, pH, Temperature and transparency at (P<0.05)while negative correlation exist between zooplankton, BOD5, DO, Nitrate and Phosphate at (P<0.05). Keywords: Distribution, Diversity, Reservoir, Wasai, Zooplankton.

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ASSESSMENT OF THE FEATURES OF EXTREME LOW TEMPERATURES OF THE SURFACE AIR LAYER IN THE LAKE SEVAN BASIN (ARMENIA)

News of the Tula state university. Sciences of Earth ◽

10.46689/2218-5194-2020-3-1-52-64 ◽

2020 ◽

Vol 3 (1) ◽

pp. 52-64

Author(s):

V.J. MARGARYAN ◽

Keyword(s):

Low Temperatures ◽

Temporal Distribution ◽

Thermal Conditions ◽

Absolute Minimum ◽

Lake Sevan ◽

Air Temperatures ◽

Daily Data ◽

The Absolute ◽

Spatio Temporal ◽

Surface Air Layer

The study is aimed to assess the patterns of spatio-temporal distribution of the extreme low temperatures of the Lake Sevan basin, their impact on the surrounding natural landscape landscape. As the source material, observations of daily data on the extremes of the minimum temperatures of the surface air layer at seven meteorological stations of the basin for the entire period (1891-2018). The methods used are mathematical-statistical, extrapolation, analytic, correlation, cartographic. A correlation was obtained between the average annual and annual absolute minimum values, as well as between the annual absolute minimum temperatures and the height of the area above sea level. The obtained relationships can be used to assess the thermal conditions of unexplored or little studied territories. As a result, a map of the spatial distribution of the annual absolute minimum temperatures of the surface air layer in the lake Sevan basin was compiled. Main conclusions. An analysis of the trend lines of temporary changes in the absolute minimum air temperatures shows that, at all weather stations currently operating in the basin, the absolute minimum temperatures tend to increase both monthly and annual...

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