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The evaluation of soil nutrient quality is based on the data of soil resources surveys and the requirements of the use of the soil (such as agriculture) to assess and measure the value and potential of the use of soil resources. Due to the development of disciplines and the limitation of technical conditions, the evaluation of soil nutrient quality generally used qualitative assessment methods in the past, that is, various qualitative vocabularies were used to evaluate the performance of soil in production and utilization. With the application of information technology in soil research, more and more depends on quantitative mathematical methods. Because GIS has the function of managing spatially uneven distribution of resources, more and more reports have been published on the use of GIS for soil evaluation at the national or provincial level. Soil nutrient quality was evaluated using a soil nutrient analyzer using database reclassification and data integration.
To collect data from the second national soil survey (including reports and maps) of 18 cities and counties in Hainan Province, and draw the sampling point map. Since there is no latitude and longitude coordinate data for the second soil survey sample, reference to previous studies used township-level administrative district maps to extract the center coordinates of each village as the location of sampling points in the village, using the nutrient contents of all the samples in each village. The arithmetic mean value is used as the soil nutrient content of the sampling point. The soil samples measured by the soil nutrient tester were spatially interpolated using soil sampling point comprehensive index method. The method first determined the soil nutrient quality evaluation factors and their weights, and comprehensively scored sampling points according to the obtained weights. The specific approach is to perform a simple grading process on the nutrient element content of each soil sampling point, and determine its score against the level and position in the corresponding grading table. After obtaining the single factor score for each index of each sample point, Combined with its weight coefficient in soil nutrient quality, according to the principle of multiplication and multiplication in fuzzy mathematics, it is the comprehensive evaluation index value of soil nutrient quality.
Through the measurement and analysis of the soil nutrient analyzer, it was found that comprehensive assessment of soil nutrient quality should be based on the soil characteristics and existing conditions in the region, draw on current research results, select factors that have a greater impact on the growth and development of crops and have a relatively independent, as soil nutrients Quality evaluation factor. The indicators selected in this study were: pH, organic matter, alkaline nitrogen, available K, and available P. The collected soil samples were air-dried, ground, sieved, and then subjected to laboratory analysis.
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Automobile Oxygen Sensor is a key feedback sensor in the control system of electric injection engine. It is also a key part to control automobile exhaust emission, reduce automobile pollution to environment and improve the quality of automobile engine fuel combustion. The oxygen sensor is installed on the engine exhaust pipe.
Application: Cars
Q: How do I know the O2 sensor is good or not?
A: The only way to know if the O2 sensor is functioning normally is to check its responsiveness to changes in the air/fuel mixture, by Voltage Measurement or Waveform Simulation.
Use a 10-megaohm digital voltmeter. Hook up the voltmeter's red probe to the sensor's signal wire and the black probe to engine ground. (Use back probe method, DO NOT pierce the wire.) For a good sensor, voltage should fluctuate constantly between 0.1 and 0.9 volts after starting the engine for 2 or 3 minutes.
Wideband Oxygen Sensor,Rear O2 Oxygen Sensor,Camry Oxygen Sensor,5 Wires Sensor
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