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In order to maintain sustainable agriculture, the flow in irrigation systems needs to be managed remotely and finely to achieve efficient use of water resources. This research develops a flow measuring device that integrates measurement and control to achieve precise flow regulation under remote control. The device chooses the angular regulating valve as the actuation component to control the flow. By the experimental study of the valve body working characteristics, this paper (1) establishes the relationships among the pressure in front of the valve, the valve body opening and the pipeline flow; (2) establishes the relationship between the valve opening degree and the number of driving pulses of the stepper motor, and (3) designs the opening decision and flow measurement software. The experiment shows that the flow coefficient of the valve body is 84.61, and there is no leakage loss when closed. It also shows that the regulation curve matches the law of fast-opening features. The established relationship and the correlation coefficient between the performance parameters and the measured value are both greater than 0.99, indicating a decent performance of fitness. In a test where the pipeline pressures were 0.10, 0.20, and 0.30 MPa, the average duration of flow regulation was 62.48 s, with a maximum overshoot of 5%, and a maximum steady-state error of 6%. The experiment also showed that the higher the pressure is, the better the regulation effect is. The flow measurement error under varied pressure is below 3%. With its simple structure, fast flow regulation time, and high accuracy, this device meets the requirements of flow management in irrigation systems. It can be used in a variety of flow rate remote monitoring and control scenarios.

Damages and deaths due to a tropical cyclone (TC) can easily occur at three places belong to a TC: the small ring area (SRA) of maximum sustaining wind around TC eye, the large ring area (LRA) of the rotating wind field around SRA and the skin air belt (SKAB) around LRA. However, weather forecasters only use the intensity of the SRA of a TC as the proxy to gauge the whole TC intensity, which led to many “non-major” TCs proved to be “deadly” TCs. This is called as “over-generalization problem” (OGP). Here we introduce a new way to measure the intensity of a TC. After investigating 156 deadly TCs in North Atlantic, we found an important feature: 83.3% of the top 156 deadliest TCs usually made landfalls along “five major tracks”. Furthermore, we found that the new intensity of those “deadliest” TCs kept almost unchanged with the increasing of time intervals at earlier stage from the genesis points, whereas the new intensity of those “safe” TCs increased in a line with much steeper slope. Using these two features, weather forecasters can have two more options to identify those “non-major” and “deadly” TCs by SSHS in future.

Contemporary references to global warming pertain to the dramatic increase in monthly global land surface temperature (GLST) anomalies since 1976. In this paper,we argue that recent global warming is primarily a result of natural causes; we have established three steps that support this viewpoint. The first is to identify periodic functions that perfectly match all of the monthly anomaly data for GLST; the second is to identify monthly sea surface temperature (SST) anomalies that are located within different ocean basin domains and highly correlated with the monthly GLST anomalies; and the third is to determine whether the dramatically increasing (or dramatically decreasing) K-line diagram signals that coincide with GLST anomalies occurred in El Ni&#241o years (or La Ni&#241a years). We have identified 15,295 periodic functions that perfectly fit the monthly GLST anomalies from 1880 to 2013 and show that the monthly SST anomalies in six domains in different oceans are highly correlated with the monthly GLST anomalies. In addition,most of the annual dramatically increasing GLST anomalies occur in El Ni&#241o years; and most of the annual dramatically decreasing GLST anomalies occur in La Ni&#241a years. These findings indicate that the “ocean stabilization machine” might represent a primary factor underlying the effect of “global warming on climate change”.

The earth-atmosphere system is an energy equilibrium system, including cooling and heating systems. The conception of “atmospheric heat engine (AH Engine)” was put forward very early in the research of heating processes. However, in the field of research on atmosphere cooling, there is no corresponding academic conception. Here we show how the atmosphere cooling engine (AC Engine) is discovered. The results show that there is a huge cooling center between the subtropical zone of northern hemispheres and the subtropical zone of southern hemispheres in the stratosphere, which is the result of AH engine. In the lower latitudes of the upper troposphere, there is an atmospheric heating belt that reaches directly to the surface of the ocean. In the global ocean surface, there are five heating centers and one cooling center, which are the results of Ocean Stabilization Machine (OSM). Therefore, there are 23 short-term global climate warming trends and 23 short-term global climate cooling trends of Global Mean Lan/Oceans Temperature Anomalies Index, which are actually the result of fluctuations of AH engine, AC engine and OSM, and how the mechanism works by AH engine, AC engine and OSM is also explained.