A Wireless Sensor Network-Based Ubiquitous Paprika Growth Management System

Wireless Sensor Network (WSN) technology can facilitate advances in productivity, safety and human quality of life through its applications in various industries. In particular, the application of WSN technology to the agricultural area, which is labor-intensive compared to other industries, and in addition is typically lacking in IT technology applications, adds value and can increase the agricultural productivity. This study attempts to establish a ubiquitous agricultural environment and improve the productivity of farms that grow paprika by suggesting a ‘Ubiquitous Paprika Greenhouse Management System’ using WSN technology. The proposed system can collect and monitor information related to the growth environment of crops outside and inside paprika greenhouses by installing WSN sensors and monitoring images captured by CCTV cameras. In addition, the system provides a paprika greenhouse environment control facility for manual and automatic control from a distance, improves the convenience and productivity of users, and facilitates an optimized environment to grow paprika based on the growth environment data acquired by operating the system

Study on an Agricultural Environment Monitoring Server System using Wireless Sensor Networks

This paper proposes an agricultural environment monitoring server system for monitoring information concerning an outdoors agricultural production environment utilizing Wireless Sensor Network (WSN) technology. The proposed agricultural environment monitoring server system collects environmental and soil information on the outdoors through WSN-based environmental and soil sensors, collects image information through CCTVs, and collects location information using GPS modules. This collected information is converted into a database through the agricultural environment monitoring server consisting of a sensor manager, which manages information collected from the WSN sensors, an image information manager, which manages image information collected from CCTVs, and a GPS manager, which processes location information of the agricultural environment monitoring server system, and provides it to producers. In addition, a solar cell-based power supply is implemented for the server system so that it could be used in agricultural environments with insufficient power infrastructure. This agricultural environment monitoring server system could even monitor the environmental information on the outdoors remotely, and it could be expected that the use of such a system could contribute to increasing crop yields and improving quality in the agricultural field by supporting the decision making of crop producers through analysis of the collected information

Effective Photon Management of Non-Surface-Textured Flexible Thin Crystalline Silicon Solar Cells

Thin crystalline silicon (c-Si) showing outstanding flexibility has been considered as an active material for flexible solar cells. However, an effective photon management should be developed for thin c-Si, which shows severe light absorption loss. Here, we introduce random inverted-pyramidal polydimethylsiloxane (RIP-PDMS) films on the surface of the thin c-Si solar cell to simultaneously secure high absorption and flexibility. Attaching the RIP-PDMS film on the front surface of the device can significantly reduce surface reflection; near-infrared light recycling can be further improved by attaching a metal-coated RIP-PDMS film on the rear surface of the device. Notably, thin c-Si solar cells with RIP-PDMS films have an efficiency of 18.4% and exhibit a constant efficiency during 1,000 repeated bending tests with a bending radius of 10 mm. Also, finite-difference time-domain simulations confirm that the RIP-PDMS films increase the light diffusion and optical path length inside the c-Si

Study of the Ubiquitous Hog Farm System Using Wireless Sensor Networks for Environmental Monitoring and Facilities Control

Many hog farmers are now suffering from high pig mortality rates due to various wasting diseases and increased breeding costs, etc. It is therefore necessary for hog farms to implement systematic and scientific pig production technology to increase productivity and produce high quality pork in order to solve these problems. In this study, we describe such a technology by suggesting a ubiquitous hog farm system which applies WSN (Wireless Sensor Network) technology to the pig industry. We suggest that a WSN and CCTV (Closed-circuit television) should be installed on hog farms to collect environmental and image information which shall then help producers not only in monitoring the hog farm via the Web from outside the farm, but also facilitate the control of hog farm facilities in remote locations. In addition, facilities can be automatically controlled based on breeding environment parameters which are already set up and a SMS notice service to notify of deviations shall provide users with convenience. Hog farmers may increase production and improve pork quality through this ubiquitous hog farm system and prepare a database with information collected from environmental factors and the hog farm control devices, which is expected to provide information needed to design and implement suitable control strategies for hog farm operation

Tunnel Barrier Engineering of Titanium Oxide for High Non-Linearity of Selector-less Resistive Random Access Memory

In this study, the effect of the oxygen profile and thickness of multiple-layers TiOx on tunnel barrier characteristics was investigated to achieve high non-linearity in low-resistance state current (I-LRS). To form the tunnel barrier in multiple-layer of TiOx, tunnel barrier engineering in terms of the thickness and oxygen profile was attempted using deposition and thermal oxidation times. It modified the defect distribution of the tunnel barrier for effective suppression of ILRS at off-state (1/2V(Read)). By inserting modified tunnel barrier in resistive random access memory, a high non-linear I-LRS was exhibited with a significantly lowered I-LRS for 1/2V(Read). (C) 2014 AIP Publishing LLC.ope

Effect of a Self-Limited Reset Operation on the Reset Breakdown Characteristics of a Monolithically Integrated 1T1R RRAM

The reset breakdown of resistive random access memory (RRAM) significantly degrades device endurance. We suppressed reset breakdown by optimizing the reset operation in an HfO2-based 1T1R RRAM device. The effective gate-to-source voltage V-GS(eff) is reduced by increasing the RRAM resistance during the reset operation. By applying the optimum VGS, we can both guarantee a sufficient reset current and suppress reset breakdown. The experimental results confirmed improved endurance characteristics without a degraded resistance ratio. (C) 2017 The Electrochemical Society. All rights reserved.11sciescopu

Threshold switching behavior of Ag-Si based selector device and hydrogen doping effect on its characteristics

The effect of hydrogen treatment on the threshold switching property in a Ag/amorphous Si based programmable metallization cells was investigated for selector device applications. Using the Ag filament formed during motion of Ag ions, a steep-slope (5 mV/dec.) for threshold switching with higher selectivity (∼105) could be achieved. Because of the faster diffusivity of Ag atoms, which are inside solid-electrolytes, the resulting Ag filament could easily be dissolved under low current regime, where the Ag filament possesses weak stability. We found that the dissolution process could be further enhanced by hydrogen treatment that facilitated the movement of the Ag atoms