Sung-Eon Cho

A Study on Greenhouse Automatic Control System Based on Wireless Sensor Network

The system proposed in this paper collects temperature of leaves and humidity on leaves of crop. As well as greenhouse environmental information such as temperature, humidity, etc. Crop diseases, especially, have deep relationship not only with indoor environmental factors but also with humidity lasting time on leaves and temperature of leaves. Accordingly, monitoring crop itself is as important as monitoring indoor environments. Using these collected greenhouse environmental data, indoor environments can be more effectively controlled, and monitoring crop itself can contribute to improve productivity and to prevent crops from damages by blight and harmful insects. In addition, it will be possible for farmers to do control plant growth through closely studying relationship between indoor environmental information and monitored information on crop itself. Collected data can be stored to database either in server installed in greenhouse or to remote server. It is made possible to collect information and control effectively and automatically greenhouse in the site or from a remote place through web browser. System components are: temperature sensor, humidity sensor, leaf temperature sensor, leaf humidity sensor, Zigbee based wireless sensor node, relay nodes for automatic control, and data server to store greenhouse information. The system is implemented using low power wireless components, and easy to install.

Comparison of open pulled straw (ops) vs glass micropipette (gmp) vitrification in mouse blastocysts

The purpose of this study was to investigate the use of a glass micropipette (GMP) as a vessel for vitrification of mouse blastocysts, and to compare the post-thaw survival of these blastocysts with those cooled in open pulled straws (OPS). The GMP vessel permits higher freezing and warming rates than OPS due to the higher heat conductivity of glass and lower mass of the solution containing the embryos. Groups of 6 mouse blastocysts were sequentially placed into 2 vitrification solutions before being loaded into either the OPS or GMP vessels and immersed into LN2 within 20 to 25 sec. Post-thaw blastocysts were serially washed in 0.25 and 0.15 M sucrose in holding medium (HM) and modified human tubal fluid medium (mHTF), each for 5 min, and then cultured in mHTF supplemented with 10% FCS for 24 h. The rate of blastocyst re-expansion did not differ significantly for OPS (93.5%) and GMP (95.0%) methods (P<0.05). The hatching rate in OPS (88.7%) was similar to that in GMP (90.0%) but was lower than for the unvitrified control embryos (98.3%, P<0.05). To determine the optimal embryo population per GMP vessel, the pipettes were loaded with 2 to 10 embryos. The rate of blastocyst re-expansion after vitrification was significant for 2 to 4 embryos than for 6 to 10 embryos per vessel. In addition, the rate of blastocyst re-expansion was significantly lower if blastocysts were vitrified in the wide rather than the narrow portion of the micropipette (100 vs 87.5%; P<0.05) even when only 4 blastocysts were loaded per vessel. These results indicate that both vitrification vessels can provide high rates of embryo survival. However, the GMP vessel does not need a cap to protect the vessel from floating after immersion in LN2. The number and location of the embryos (narrow versus wide portion of capillary) were considered to be limiting factors to the viability of mouse embryos.

Intelligent model design of cluster supply chain with horizontal cooperation

Intelligent model design of complex system becomes a key issue for organization responsiveness to uncertainties. In the real business world, the rule of competition between one firm verse another is replaced by a chain verse another chain, the cooperation is the same, where does it occur? At industrial cluster, there are a multiple of rivals or potential competitors for each member of value chain, industrial cluster location not only contains a couple of focal firms locating at the same tier, but includes the corresponding upstream and downstream firms as well, all of which concentrate on a close geographical site. For adopting to ever-changing market and sever competition, it is most likely to form multiple paralleled single supply chains for each focal firm of industrial cluster, these paralleled single supply chains compete and cooperate with each other. Recent researches regarding supply chain design mainly focus on a limited tier in single supply chain, which only take into account vertical cooperation and ignore the across-chain horizontal one. This paper, based on cluster supply chain, provides a novel framework and approach to design cluster supply chain without across-chain horizontal cooperation, then by introducing item allocation proportion of vertical and horizontal cooperation (α: 1−α), the cluster supply chain design with across-chain horizontal cooperation is developed, then presents a hybrid method to find solution, at last, computational study is presented to investigate values of decision variables and their influence on cluster supply chain design.

SOX Act and IT Security Governance

This paper discusses the effects of Sarbanes-Oxley (SOX) Act on corporate information security governance practices. The resultant regulatory intervention forces a company to revisit its internal control structures and asses the nature and scope of its compliance with the law. This paper reviews the implications emerging from the mandatory compliance with Sarbanes-Oxley (SOX) Act. Issues related to IT governance and the general integrity of the enterprise are also identified and discussed. Industry internal control assessment frameworks, such as COSO and COBIT, are reviewed and their usefulness in ensuring compliance evaluated.

AoA Localization System Design and Implementation Based on Zigbee for Applying Greenhouse

In this paper, we showed AoA localization system design and implementation based on Zigbee for applying Greenhouse. The proposed system can be realized with low-cost. Our system can provide various applications in the Greenhouse. That can be output forecasts or equipment control by sector. In this paper, We build a testbed and has obtained the result from the repeated tests to achieve the measurement of location with the accuracy of average 35 cm.

A study on the medical image transmission service based on IEEE 802.15.4a

In this paper, the transmission service for medical image is proposed via IEEE 802.15.4a on WPAN environment. Also, transmission and receiving performance of medical image using TH UWB-IR system is evaluated on indoor multi-path fading environment. On the results, the proposed scheme can solve the problem of interference from the medical equipment in same frequency band, and minimize the loss due to the indoor multi-path fading environment. Therefore, the transmission with low power usage is possible.

Greenhouse Environment Monitoring and Automatic Control System Based on Dew Condensation Prevention

Dew condensation on the leaf surface of greenhouse crops causes diseases by fungus, and thus badly affecting the growth of the crops. In this paper, we present a WSN based automatic control system to prevent dew condensation in the greenhouse environments. The system is composed of sensor nodes for collecting data, base nodes for processing collected data, relay nodes for adjusting the environment inside a greenhouse and an environment server for storage and processing of collected data. Using the Barenbrug formula for calculating the dew point on the leaves, this system is realized to prevent a dew condensation phenomenon on the crops surface acting as an important element in diseases generation. We also constructed a test bed the usual greenhouse in order to verify the performance of our system with regard to dew condensation control.

Protecting Your Privacy with a Mobile Agent Device in RFID Environment

Radio Frequency Identification (RFID) Technology is a contactless automatic identification technology using radio frequency. For this RFID technology to be widely spread, the problem of privacy invasion should be solved. There are many research works in progress to solve the RFID privacy problems. Most of works for solving this problem have focused on developing light-weight cryptographic modules which can be embedded into RFID tags, but some of them used a proxy agent approach that control communications between the tag and the reader for protecting user privacy. The later approach is very useful and practical in terms of manufacturing low-cost tag hardware. However, all schemes of this approach have some problems in ownership transfer and forgery detection. In this paper, we are focusing on the proxy agent approach and we suggest an advanced agent scheme that guarantees not only privacy protection but also forgery detection. And our scheme is more scalable than other agent schemes so far.

A robust and secure time-domain ICI canceller for OFDM based ubiquitous systems in time-varying multipath channels

A robust and secure time-domain cancellation is proposed for inter-carrier interference (ICI) reduction in OFDM systems for ubiquitous environments. To cope with the problem of the conventional time-domain canceller, which does not work in deep fades, simple repetition (de)coding and modulation order increasing techniques are exploited in our proposal. The approximated repetition decoding provides reliable symbols in the regeneration operation, and the increased modulation order maintains the spectral efficiency. Simulation results indicate that the proposed method using 16QAM significantly improves the BER performance compared with the conventional method using QPSK, while the spectral efficiency is maintained. Moreover, the proposed method using 64QAM concurrently improves both the BER performance and the spectral efficiency.

The accurate performance evaluation of time hopping UWB systems with pulse based polarity

The bit rate performance of the time hopping impulse radio UWB system with the pulse based polarity is analyzed. It is well known that the pulse polarity helps reduce the spectral spike appearing in the conventional impulse radio system. This paper provides the method for accurately modeling the multiple access interference(MAI) in the system with the pulse polarity. The characteristic function is used to consider the MAI. We also show the MAI can be simplified as Gaussian random variable when the number of pulses representing an information symbol or the pulse rate becomes large. It is obtained directly from approximating the Characteristic Function of the MAI in case of the large number of pulses. Some results have been shown to prove validity for our method. The results also show with the total processing gain fixed, increasing the pulse rates proves the system performance. But the system without the pulse polarity does not.