scholarly journals Design of the Humidity and Temperature Controller Using the Moistures of Leaf and Soil

2021 ◽  
Vol 16 (4) ◽  
pp. 421-433
Author(s):  
Walaa Kareem Khalaf ◽  
Yong Tae Kim
Keyword(s):  
Air Temperature ◽  
Output Voltage ◽  
Water Flow Rate ◽  
Reference Value ◽  
Field Capacity ◽  
Small Range ◽  
Environment Change ◽  
Moisture Sensor ◽  
Temperature And Humidity ◽  
And Control

A controlling of air temperature and humidity is important issue because environment change has effects on growing stages of plants. In this study a (DHT22, AH-300u, YL-69) sensors and a microcontroller (arduino Uno) have been used to monitoring and controlling the temperature, humidity of air and control irrigation process based on monitoring the moistures of (soil, plant leaf) data inside the greenhouse prototype. The findings during the experiment time (4 days) indicates that the air temperature maintain at reference value 27℃ and relative humidity has a slightly increase by 0.7 from reference value (82). The output voltage of soil moisture sensor has been monitor at a small range (0.8 v - 1 v) roughly stable, and it is near to field capacity. The output voltage of leaf moisture sensor is slightly increased. From this study it has been observed that the proposed system in a greenhouse is a good procedure to maintain air temperature and humidity inside the greenhouses and effective for monitoring air factors as well as soil and leaf moistures. regarding irrigation process, a decision table has been suggested to control the irrigation water flow rate according to output voltage of each of soil and leaf moistures sensors.

scholarly journals Smart Farming for Lowland Strawberry (Fragaria x ananassa) Production

2021 ◽  
Vol 12 (3) ◽  
pp. 1797-1804
Author(s):  
Jayson J. Elenzano Et.al
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Moisture Sensor ◽  
Smart Farming ◽  
Temperature And Humidity ◽  
The Status ◽  
Temperature Parameter ◽  
Arduino Microcontroller ◽  
And Control ◽  
Parameter Values

The developed system monitors the humidity levels, moisture content of the soil and surrounding temperature. Parameter values such as maximum and minimum temperature, maximum and minimum humidity values can be monitored accordingly by sending an sms to the system using arduino microcontroller, gsm module, moisture sensor and dht11 temperature/humidity sensor. This design maybe used for monitoring and controlling temperature and humidity value via sms. This system monitors and control the water content of the soil using a moisture sensor which runs under the control of a microcontroller, a dht 11 sensor to control and monitor the greenhouse humidity and proper temperature and a short messaging system (sms) to notify the caretaker/ owner on the moisture level content and temperature/humidity of the greenhouse. The system monitored and maintains the proper temperature, humidity and soil moisture content inside the greenhouse. The device has been successfully tested under simulated conditions and showed the ability of controlling temperature, humidity and soil moisture. The system notified the caretaker/farmer via short messaging system (sms) for the notification status (information) and triggering the water pump. The device showed the capability of sending sms holding the latest temperature and humidity information and also the status of the greenhouse.

scholarly journals State Switched Discrete-Time Model and Digital Predictive Voltage Programmed Control for Buck Converters

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3451
Author(s):  
Wei Wang ◽  
Gaoshuai Shen ◽  
Run Min ◽  
Qiaoling Tong ◽  
Qiao Zhang ◽  
...  
Keyword(s):  
Discrete Time ◽  
Output Voltage ◽  
Reference Value ◽  
System Stability ◽  
Duty Ratio ◽  
Time Model ◽  
Reference Tracking ◽  
Discrete Time Model ◽  
Averaged Models ◽  
And Control

Switched mode power converters are nonlinear systems, and it is a constant challenge to improve their modeling accuracy and control performance. In this paper, a State Switched Discrete-time Model (SSDM) is proposed, which achieves a higher accuracy at a high frequency than that of conventional state averaged models. Instead of averaging the converter states for approximation, the states within each switching cycle are considered in the modeling. Based on total differential equations of switching-ON and switching-OFF durations, the inductor current and output voltage within a cycle are accurately calculated, which derives the SSDM. Furthermore, a Digital Predictive Voltage Programmed (DPVP) control strategy is derived through the SSDM. Through voltage prediction, a suitable duty ratio is calculated that regulates the output voltage to its reference value in the minimum switching cycles. In this way, the converter achieves a very fast load/line transient response and reference tracking speed, and it exhibits a high stability under deviated inductance. Finally, the accuracy of SSDM and the system stability are proved by frequency response analyses and experiments.

Dry chip feedrate control using online chip moisture

TAPPI Journal ◽  
2018 ◽  
Vol 17 (05) ◽  
pp. 295-305
Author(s):  
Wesley Gilbert ◽  
Ivan Trush ◽  
Bruce Allison ◽  
Randy Reimer ◽  
Howard Mason
Keyword(s):  
Production Rate ◽  
Control Strategy ◽  
Rate Control ◽  
Near Infrared ◽  
Dry Mass ◽  
The Other ◽  
Process Variability ◽  
Moisture Sensor ◽  
Feedback Control Strategy ◽  
And Control

Normal practice in continuous digester operation is to set the production rate through the chip meter speed. This speed is seldom, if ever, adjusted except to change production, and most of the other digester inputs are ratioed to it. The inherent assumption is that constant chip meter speed equates to constant dry mass flow of chips. This is seldom, if ever, true. As a result, the actual production rate, effective alkali (EA)-to-wood and liquor-to-wood ratios may vary substantially from assumed values. This increases process variability and decreases profits. In this report, a new continuous digester production rate control strategy is developed that addresses this shortcoming. A new noncontacting near infrared–based chip moisture sensor is combined with the existing weightometer signal to estimate the actual dry chip mass feedrate entering the digester. The estimated feedrate is then used to implement a novel feedback control strategy that adjusts the chip meter speed to maintain the dry chip feedrate at the target value. The report details the results of applying the new measurements and control strategy to a dual vessel continuous digester.

Strretlight pole metal as the medium of Tetragonula sp nest in Indralaya, South Sumatra

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Hanifa Marisa
Keyword(s):  
Zea Mays ◽  
Air Temperature ◽  
Hevea Brasiliensis ◽  
Citrullus Lanatus ◽  
Ground Surface ◽  
Temperature And Humidity ◽  
Surface Diameter ◽  
Very High

An investigation had been done to Tetragonula (Tetragona) sp nest at Indralaya, South Sumatra to describe the Tetragonula sp nest that use streetlight pole as nest medium during April - May 2019. Purpossive sampling is used to select the target nest. Two streetlight pole found be used by Tetragonula sp as their home. The coordinate of location, heght from ground surface, diameter of streetlight pole, air temperature and humidity, and floral species around nest, were noted. Spot coordinate are S 30 14’ 19.2498’’ and E 1040 39’ 15,3288’’ ; 1,5 m above the ground surface, 12 cm diameter pole, highest air temperature was 35 o C at daylight (April and May 2019), 80 – 90 % humidity at April-May 2019; which Switenia macrophyla, Hevea brasiliensis, Zea mays, and Citrullus lanatus floral species are planted around. Air temperature in the pole is very high, around 40 0 C during daylight.

scholarly journals The interrelationship between air temperature and humidity as applied locally to the skin: The resultant response on skin temperature and blood flow with age differences

2012 ◽  
Vol 18 (4) ◽  
pp. CR201-CR208 ◽  
Author(s):  
Jerrold S. Petrofsky ◽  
Lee Berk ◽  
Faris Alshammari ◽  
Haneul Lee ◽  
Adel Hamdan ◽  
...  
Keyword(s):  
Blood Flow ◽  
Skin Temperature ◽  
Age Differences ◽  
Air Temperature ◽  
Temperature And Humidity
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