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Between 2011 and 2012, a total of 896 pig fecal samples were collected from nine provinces in Korea, and 50 salmonella enterica susp. enterica serovar Typhimurium (S. Typhimurium) was isolated. The characteristics of the 50 strains were analyzed, and 4 strains were identified as Salmonella enterica subsp. enterica serovar 4,[5],12:i:-. Salmonella 4,[5],12:i:- could not be distinguished from S. Typhimurium through phage typing, antimicrobial resistance testing or multiple-locus variable-number tandem repeat analysis (MLVA). However, among the four Salmonella 4,[5],12:i:- strains, one (KVCC-BA1400078) was identified as a Salmonella 4,[5],12:i:- clone isolated from humans in the United States, and another (KVCC-BA1400080) was identified as DT193, which has been primarily isolated from humans and animals in European countries. The presence of Salmonella 4,[5],12:i:- in Korea poses a significant threat of horizontal transfer between pigs and humans.

The advent of IoT(Internet of Things) has triggered various kinds of USN(Ubiquitous Sensor Network) services in diverse fields. Keeping pace with the advance of USN service, many researchers have conducted studies to figure out low energy consumption of sensors. It is required to develop effective communication way with moving objects by using mobile sensors, not by using fixed sensors. This paper proposes the way to communicate effectively with moving objects and to achieve low energy consumption of sensors by controlling dynamic duty cycle based on mobility. In addition, this paper suggests the real life application for location management system of wild life animals.

Recently it is required to improve digital signage system which supports multilingual service because of the fast-growing number of foreign tourists. The existing digital signage systems obviously support various kinds of multilingual service via the internet connection. However, unfortunately, most foreign tourists are compelled to face limitations to access the real time service of multilingual contents mainly due to their limited internet conditions. This paper has designed digital signage system which supports multilingual service without the internet connection. The basic structure suggested in this paper is that smart device connects to the digital signage system without the internet connection based on Wireless Personal Area Network.

In recent years, many countries are developing aircraft navigation systems using GNSS(Global Navigation Satellite System), because GNSS has many technical and economic benefits. International organizations as ICAO(International Civil Aviation Organization) and RTCA(Radio Technical Commission for Aeronautics) set up international standards of GBAS(Ground Based Augmentation System) using GNSS and recommend countries to develop GBAS that is based on the standards. To go with the international stream, Korea Airport Cooperation has also developed GBAS. For evaluating the system, KAC and Seoul National University have performed flight tests of the developed GBAS several times and have concluded that the system has good accuracy enough to be used in aircrafts. At that time, the purpose of tests was focused on accuracy of GBAS. But integrity of the system which is important for safety of aircrafts was not tested sufficiently, because it is impossible to make erroneous situations of real GPS signals. So, at this time, we used GPS simulator which can generate GPS signals with satellite failure scenarios. The GPS simulator used in this test generates GPS signals by the scenarios organized in advance. The scenarios can include pseudorange and carrier phase error, parity error and etc. So we organized several scenarios which can includes potential errors of GPS signals and many possible cases for testing the system effectively and accurately. And we tested integrity function of the GBAS system by using GPS signals generated by the simulator. This paper introduces the implemented integrity monitoring system and algorithms used in the tests. And it describes the scenarios of satellite failure. Finally, this paper shows the results of tests.

Voice conversion is a technique that transforms the source speaker’s individuality to that of the target speaker. In this paper, we propose a simple and intuitive voice conversion algorithm that does not use training data between different languages, but uses text-to-speech generated speech rather than real recorded voices. The suggested method finds the transformed frequency by formant space warping. The formant space comprises four representative monophthongs for each language. The warping functions are represented by piecewise linear equations using pairs of four formants at matched monophthongs. Experimental results show the potential of the proposed method.