저압 에어포그 시스템을 설치한 온실의 냉방효율

In this study, the heat effectiveness and energy efficiency of the clove drying machine with control of temperature and relative air humidity were analysed. The data were carried out experimentally on a clove dryer machine that has 3 racks with staggered arrangement by varying the speed of the air flow into the drying chamber. The hot air produced from a heater and blown to the drying chamber used a fan with 3 various speed rate (1.9 m/s, 2.3 m/s, 2.8 m/s). The heat distribution on each rack was observed and analysed and compared with the energy requirements of the machine. The result showed that the heat flow on the rack evenly distributed. The fluid flow variation has the important effect. The heat will more effective with the lower air flow speed, which the higher heat transfer (q) to the clove from the heater depend on the air flow speed with the higher value 72.78 watt at the lowest positions rack with hot air speed 2.8 m/s. The energy efficiency of the machine was about 37 percent, with the highest value 39.27 percent at the air speed 2.3 m/s.

MICROCLIMATE CONTROL IN GREENHOUSES BASED ON PHYTOMONITORING DATA AND MOLLIER PHASE DIAGRAM

This paper studies an embedded monitoring system centered on ZigBee technology to realize real-time temperature and humidity monitoring, and to ensure low power consumption, high reliability, low cost, and collection of environmental information. The communication is designed using the star topology, and the whole network structure is composed of a master node and three sensor receiving nodes to realize the unlimited transmission of network data. The main control point is to determine the coordination of the scope of the ZigBee network configuration system. The ZigBee network can communicate with the host through the data port to realize the acceptance of temperature and humidity data and the sending of commands. Based on this research, this paper determines the impact of non-target parameters on the actual measurement data of the multipoint temperature and humidity sensor, and at the same time determines the key influencing factors. For HMP-45D multipoint temperature and humidity, an improved genetic algorithm (GA) combined with a support vector machine (SVM) is used to compensate humidity and temperature data, which is designed to affect the actual measurement error of the multipoint temperature and humidity sensor. This paper studies the silver forging process, compares the environmental factors of silver carving, further puts forward the control strategy of Hagoun product forging and carving environment control from the perspective of temperature and humidity, and designs the environmental temperature and humidity measurement and control system from the perspective of temperature and humidity control. The system design proposed in this paper is mainly to construct and apply the silverware forging and engraving environment temperature and humidity measurement and control system on the basis of integration and maintenance-free and verify the effectiveness and feasibility of the system in the protection of cultural relics.

In industrial production, temperature and humidity are common main manipulated parameters, especially in heat treatment industry, the temperature control is becoming more and more important. This paper from two aspects that hardware and software introduced single-chip microcomputer (SCM) C8051F intelligent temperature and humidity control system, and described schematic diagram of hardware and software. The design adds the integration of carbon dioxide concentration and light intensity detection and necessary communication function. It is a more humanized and more practical intelligent temperature and humidity measurement and control system.

The quality of tobacco baking is one of the important factors affecting the economic benefits of tobacco enterprises. Because of the low efficiency of traditional manual baking methods and the poor quality of tobacco, the economic benefits of tobacco enterprises and tobacco farmers are also greatly affected. In view of this, this research takes the temperature and humidity control as the research object, and proposes an agricultural intelligent tobacco house temperature and humidity controller based on STM32. Firstly, the general design scheme, hardware circuit design scheme and software design scheme of the control system are described, in which the human-machine interface circuit design of the hardware circuit design is emphatically analysed, and finally, the design of this research is applied The agricultural intelligent temperature and humidity controller measures the temperature and humidity of the flue-cured tobacco house, and verifies the control effect. The results show that the temperature control accuracy based on STM32 is significantly higher than that of traditional control method, which is conducive to the improvement of tobacco baking quality. It is hoped that this study can provide a significant reference for the research of temperature and humidity control in tobacco industry in China.

Although several new solutions for greenhouse heating and environmental control are being investigated all over the world; to reduce energy consumption and environmental impacts, to increase the efficiency of energy use for plant production in protected cultivation or to take advantage of the new renewable energy sources, in Portugal the great majority of producers still rely on more conventional heating systems for an economical year round production of vegetables and flowers.The objective of this work is to review some guidelines to help the grower when choosing the best heating solutions for different crops and cultivation systems.First, the level of heating required is defined and the correspondent heating power is analysed.Secondly, the main heating systems are mentioned including their components, characteristics, effects on greenhouse climate, soil and plant temperature.Relative costs of equipment and energy consumption are analyzed and some examples of practical solutions are presented from vegetable and flower production growers.Finally, several strategies to reduce the energy required for greenhouse heating are given and studied, including greenhouse structures, covering materials, thermal screens, air temperature and humidity control.

Budidaya jamur kuping adalah salah satu sumber pangan yang baru. Budidaya ini memerlukan sistem pengendalian suhu dan kelembaban yang tepat untuk menghasilkan kualitas jamur kuping yang baik. Sekarang ini sudah banyak sistem pengendali suhu dan kelembaban untuk jamur baik secara manual ataupun otomatis, namun masih banyak kekurangannya seperti pemakaian alat yang mahal, kurang praktis perakitannya, dan pengoprasiannya tidak mudah. Penelitian ini bertujuan merancang dan membuat prototipe suatu sistem pengendali suhu dan kelembaban untuk budidaya jamur kuping yang lebih baik dari sistem-sistem pengendali yang sebelumnya. Metode penelitian ini dilakukan melalui 2 tahap utama yaitu perancangan konseptual dan perancangan alat dan sistem. Tahap perancangan konseptual meliputi identifikasi kebutuhan, perancangan sistem, dan pemilihan komponen. Tahap selanjutnya adalah penerapan alat dan sistem yang meliputi rangkaian mikrokontroler, sensor, alat pemanas, alat pendingin, perancangan sirkuit elektronik, hardware, pemrograman alat dan terakhir perakitan alat. Penelitian ini menghasilkan prototipe alat pengatur temperatur dan kelembaban dengan menggunakan mikrokontroler ATmega16, yang mampu meningkatkan kecepatan respon sistem pengendali temperatur pada budidaya jamur yang dilakukan secara otomatis, mudah dalam pengoperasian pengendali, praktis perakitannya, memiliki kemampu-rawatan yang mudah, dan memperbaiki realibilitas sistem terdahulu yang mana masih dilakukan secara manual. Alat pengatur temperatur dan kelembaban ini dapat membantu setiap petani jamur kuping baik yang sudah terlatih maupun belum. Hasil pemakaian alat ini dapat meningkatkan produktivitas hasil panen.

Optimal and near-optimal indoor temperature and humidity controls for direct load control and proactive building demand response towards smart grids

For continuous improvement of productivity, accurate, stable, and reliable control of temperature and humidity is important in industrial production. Accurate prediction of air temperature and humidity can improve the predictability and stability of air conditioning control systems. In this paper, based on the cloud database of industry settings, an improved prediction model based on backpropagation (BP) neural networks was established to forecast indoor air temperature (IT) and relative humidity (IH) every 10 min and 6-72 h in advance. The experimental building was in Chongqing, a typical humid, hot-summer, and coldwinter area in China. The test data were used to determine the optimal parameters of the neural network model. The experimental results showed that the IT and IH predictions by our model have strong correlations with the actual data, with the coefficients of determination being 0.9897 and 0.9778, respectively. Compared with other literature, our model was more effective in temperature prediction. The presented method can be used for the prediction and control of the indoor temperature and relative humidity in industrial production.

ABSTRACTThis article presents an intelligent Filtering Facepiece Respirator (FFR) with a self-adjustable ventilation fan for improved comfort. The ventilation fan with an intelligent control aims to reduce temperature, relative humidity, and CO2 concentrations inside the facepiece. Compared with a previous version of the FFR, the advantage of this new FFR is the intelligent control of the fan's rotation speed based on the change in temperature and relative humidity in the FFR dead space. The design of the control system utilizes an 8-bit, ultra-low power STC15W404AS microcontroller (HongJin technology, Shenzhen, China), and adopts a high-precision AM2320 device (AoSong electronic, Guangzhou, China) as temperature and relative humidity sensor so that control of temperature and relative humidity is realized in real time within the FFR dead space. The ventilation fan is intelligently driven and runs on a rechargeable lithium battery with a power-save mode that provides a correspondingly longer operational time. Meanwhile, the design is simplistic. Two experiments were performed to determine the best location to place the fan.

In recent years, due to the energy crisis and serious environmental problems, the use and development of new energy has become the focus of research. Therefore, the application of new energy technologies has increased the demand for direct current to direct current (DC-DC) converters. The improvement of converter capability effectively enhances the functions of DC-DC converters, which makes it easy for secondary converters to meet the requirements of voltage gain, and expands the input voltage range of DC-DC converters, thereby having a good prospect in new energy applications. However, due to the many drawbacks of the quadratic Boost converter, such as pressure rise limitation, high switching stress, in order to reduce the working pressure of the improved quadratic Boost high gain converter and improve its operating performance, it is necessary to optimize it. Based on the application scenario of an modified converter for quadratic Boost high gain DC-DC, and taking the constant off time control method as an example, this paper conducted research to accurately recognize the current status of the converter and improve the utilization efficiency of the converter. In this paper, four groups of traditional converters and two types of improved quadratic Boost high gain DC-DC converters were selected as experimental objects for comparative analysis of images and data. The results showed that the conversion efficiency of the constant off time control method in the modified DC-DC converter based on quadratic high gain was 7.03 % higher than that of the traditional converter, while also improving the conversion efficiency of voltage gain and reducing switching stress, with higher safety. This indicated that the improved DC-DC converter with secondary high gain has better effects and wider application scenarios, thereby better serving new energy systems.

Automated, high temporal resolution mechanics measurements during incubation of contractile tissues

Creep behavior of the ZK60 magnesium alloy was investigated using impression creep technique. The tests were carried out under constant punching stress at high temperatures (175, 200 and 225 °C) under low stresses (25, 50, 75 and 100 MPa) and at low temperatures (100, 125 and 150 °C) under high stresses (100, 125, 150 and 175 MPa). The creep mechanism of the extruded ZK60 magnesium alloy is grain boundary sliding by dislocation climbing obtained at low temperature and high pressure. At high temperature and under low pressure, the creep mechanism of the extruded ZK60 magnesium alloy is grain boundary diffusion by grain boundary sliding. The initial microstructure of the extruded ZK60 magnesium alloy was composed of mainly Mg phase and a little MgZn phase. Under the conditions of low temperature and high pressure, MgZn2 phase precipitated during creep deformation. Under the conditions of high temperature and low pressure, MgZn2 phase and a small amount of Zr-Zn phase precipitated during creep deformation. The creep resistance of magnesium alloy ZK60 under the conditions of low temperature and high pressure is better than under the conditions of high temperature and low pressure.

A compressor blade failure was experienced at the 69 MW gas turbine of a combined cycle (C.C.) unit after four years operation since the last overhaul (January 2005). The unit accumulated 27,000 service hours and 97 start-ups since the last overhaul. This unit consists of four gas turbine stages and 19 compressor stages and operates at 3600 rpm. In 2006, the unit was equipped with a fogging system at the compressor air inlet duct to increment unit power output during high ambient temperature days (hot days). These fog water nozzles were installed upstream of the compressor inlet air filter without any water filter/catcher before the water spray nozzles. Three unit failure events occurred at small periods, which caused forced outage. The first failure occurred in December 2008, a second event in March 2009 and the third event in May 2009. Visual examination carried out after the first failure event indicated that the compressor vanes (diaphragms) had cracks in their airfoils initiating at blade tenons welded to the diaphragm outer shroud at stages 3, 8, 9, 10 and 11. Also, many stationary vanes and moving blades at each stage of the compressor showed foreign object damage (FOD) and fractures at the airfoil. Visual examination performed for the second failure event after 60 unit operation hours indicated that many compressor vanes (diaphragms) and moving blades had FOD at the airfoil. This was attributed to fractures of the fogging system water spray nozzle, which were then induced to the compressor flow path channel at high velocity causing the above-mentioned damage. Visual examination completed upon the third failure event after two unit startup attempts indicated damage of compressor stationary vanes and moving blades principally at stages 12 to 16, and also stages 17 to 19. The damage consisted of airfoil fracture in stationary vanes and moving blades, FOD, moving blade tip rubbing, and bending of stationary vanes, moving blades and diaphragm shrouds. A laboratory evaluation of stationary vane tenon fracture indicated a high cycle fatigue (HCF) failure mechanism, and crack initiation was accelerated by corrosion picks on blade surfaces due to high humidity air generated by the fogging system. Stationary vane damage was caused by a rotating stall phenomenon, which generates vibratory stresses in stationary vanes and moving blades during unit start-ups. During the third failure event, stationary vane HCF damage was highly accelerated due to pre-existent partial fractures in tenons generated during previous failure events, which had not been detected by non-destructive tests. Stationary vane and moving blade failure was also influenced by high tenon brittleness in stationary vanes and moving blades generated during manufacture by welding (diaphragms) and repair welding (moving blades) without adequate post-weld heat treatment (stress relieving). A compressor stationary vane and moving blade failure evaluation was completed. This investigation included cracked blade metallographic analysis, unit operation parameter analysis, history-of-events analysis, and crack initiation and propagation analysis. This paper provides an overview of the compressor failure investigation, which led to identification of the HCF failure mechanism generated by rotating stall during unit start-ups, highly accelerated by corrosion generated by the fogging system and influenced by high stationary vane and moving blade brittleness as the primary contribution to the observed failure.

Development of an applicability and performance evaluation tool based on energy simulation for smart greenhouse cooling packages