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[en] The principle of 1-Wire bus protocol, the characteristics of digital temperature sensor DSISB20, humidity sensor DHT11 and the ultra low power mixed signal processor MSP430F149 are introduced, which combined with PC formed a precise collection system with 8 channel temperature and 1 channel humidity. (authors)
[en] The Wireless Sensor Network (WSN) is composed of a large number of sensor nodes with limited computation communication, and battery facilities. One of the common applications of this network is environment monitoring through sensing motion, measuring temperature, humidity and radiation. One of the basic activities in WSN is data gathering which represents a great challenge. Many routing protocols are proposed for that network to collect and aggregate the data. The most popular ones are hierarchy and data centric routing protocols. The main goal of this study is to identify the most preferable routing protocol, to be used in each mobility model. This paper studies the performance of LEACH (Low Energy Adaptive Clustering Hierarchy) from hierarchy routing protocol and direct diffusion from data centric routing protocol which is not clarified until now. Moreover, a comparison between LEACH and direct diffusion protocol using NS2 simulator will be made, and an analysis of these protocols will be conducted. The comparison includes packet delivery ratio, throughput, average energy ratio, average delay, network lifetime, and routing overhead. The performance is evaluated by varying the number of sensor nodes under three mobility models Reference Point Group Mobility Model (RPGM), Manhattan and random waypoint mobility model. Simulation results show that LEACH routing protocol has a good performance in RPGM and Manhattan than random waypoint mobility model. Direct diffusion has a good performance in random waypoint mobility model than in RPGM and Manhattan mobility model
[en] The contribution comprises analysis that is based on scientific work as a part of participation on the international research project carried out at the University of Prešov in Prešov and Vienna University of Technology entitled 'Detection and Management of Risk Processes in Building Insulation' and numbered SRDA SK-AT-0008-10. Statistical approach with correlations among humidity, time and temperature values in the space between the wall and building insulation uses the set of data obtained during the measurement series as testing using a new technology with equipment that does not influence the environment properties in the space. Therefore such real mapping can bring a real picture of possible condensation as a risk process in the building envelope.
[en] Reliability testing of cable on humidified condition has been carried out. As a result, the failure occurred due to reduction of current by increasing the resistance on rising temperature testing. For humidified condition the result which are observed did not significant at the stated condition of testing. The needed time up to the failure criteria increased as a temperature testing increased
[en] In the process of nuclear radiation measurement, often the results relied on measuring the temperature and humidity of the environment to compensate. The design of a low-cost simple temperature and humidity logger in the article, can achieve the measurements of temperature, humidity in the experimental nuclear environment. The system uses AT89 series low-cost MCU controller, domestic DHT11 temperature and humidity sensors, and RS485 protocol for remote data transfer and on-line monitoring of results. Experimental results show that the collector can achieve rapid multi-point measurements of temperature and humidity, the system is stable and reliable, is a low-cost solution, suitable for all kinds of nuclear measurement applications. (authors)
[en] An Infra-Red camera has been used to reduce errors and to save time, cost and efforts for measurement of temperature distribution. Because allowable ranges of major factors that affect results of the measurement of the IR camera had not been established yet, this study has been performed to investigate the major factors and ranges for the effective measurement techniques. In this study, surface temperature, surrounding humidity, distance between the camera and the surface, incident angle, and emissivity of the surface have been considered as the major factors for the experimental setup. Especially, it has been observed that the results of the IR camera have been affected by the surface emissivity greatly.
[en] In order to effectively hold the measuring point surroundings condition record information in nuclear fallout measuring instrument inside, the measurement data has more practical meaning, also facilitate comprehensive analysis and processing. It will have high sensitivity, low interference, easy to install characteristics of temperature and humidity, wind speed sensor and wind-direction sensors, rainfall sensor embedded into to MSP430F169 as the core of the nuclear instruments, realizing the environmental parameters of the acquisition, and in each sensor is introduced based on the theory of, will of communication between the microcontroller and sensor method and software and hardware design to do a detailed explanation. Experiments prove, the text of the design method is feasible, instrument completely can achieve in nuclear detection applications in the field of requirements. (authors)
[en] In this study, a parametric study was performed for the spraying technique used to fabricate polystyrene (PS) superhydrophobic surfaces. The spraying distance, the spraying time and the polymer concentration were selected as the parameters to be varied. Tetrahydrofuran (THF) was used for the solvent. First, a dissolved PS solution in THF was prepared. Then, the dissolved PS solution was sprayed onto the coverglass. The Nozzle size, working pressure, glove box temperature and humidity were fixed at 0.2 mm, 0.2 MPa, 23.15±0.83 .deg. C and 54.13±1.46%, respectively. After that, the surface morphology of the sprayed surface and water contact angle (WCA) were assessed by Scanning electron microscopy (SEM) and a contact angle meter. According to the spraying distance increased, the WCA was decreased in all three cases of the 1.5 vol% PS solution. However, the WCA was approximately 158 .deg. regardless of the spraying time or distance in all three cases of 6.0 vol% PS solution. The amount of PS deposited per unit area was shown to be the key parameter in determining the hydrophobicity, as expected. However, the PS concentration and the spraying distance affected the hydrophobicity regardless of the amount of PS deposited. Additionally, using least-squares method of the Origin 8.1 program fitting procedures for the WCA results, a water-contact-angle map of the PS-sprayed specimen was generated within the experimental parameters.
[en] The author surveys briefly the various factors that are to be considered in predicting the reliability of electronic instruments. Theoretical aspects of reliability are briefly described. Practical methods such as reliability prediction, redundancy, debugging and maintainability to achieve high reliability are enumerated. Effects of temperature and humidity on electronic components in general are discussed. Adverse effects of climatic conditions on nuclear electronic instruments are described and means to overcome them are suggested. Finally, the author expresses simple and inexpensive techniques to achieve high reliability. (author)
[en] This paper presents a humidity sorption sensor made with an ink-jet printing technique. Nafion was applied as a humidity sorption material. After the presentation of sensor construction and sensor fabrication technology, a lot of effort has been made for detailed sensor tests and characterization. The sensor model based on a RC transmission line with distributed parameters (Jachowicz and Senturia 1981/1982 Sensors Actuators 2 171–86) has been carefully described and validated by a comparison with the sensor empirical parameters, measured in a broad range of measurement frequencies. On the basis of achieved results, some general conclusions for humidity sorption sensors on both the sensor fabrication technology and the sensor modelling have been made and presented in this paper