Sang-Jun Han

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The process of learning the behavior of a given program by using machine-learning techniques (based on system-call audit data) is effective to detect intrusions. Rule learning, neural networks, statistics, and hidden Markov models (HMMs) are some of the kinds of representative methods for intrusion detection. Among them, neural networks are known for good(More)
Hidden Markov model (HMM) has been successfully applied to anomlay detection as a technique to model normal behavior. Despite its good performance, there are some problems in applying it to real intrusion detection systems: it requires large amount of time to model normal behaviors and the false-positive error rate is relatively high. To remedy these(More)
In the development of location-based services, various location-sensing techniques and experimental/commercial services have been used. We propose a novel method of predicting the user's future movements in order to develop advanced location-based services. The user's movement trajectory is modeled using a combination of recurrent self-organizing maps(More)
In the development of location-based services, various location-sensing techniques and experimen-tal/commercial services have been used. However, conventional location-based services are limited in terms of flexibility because they depend on the current location of the user. We propose a novel method of predicting the user's future movements in order to(More)
As the information technology grows interests in the intrusion detection system (IDS), which detects unauthorized usage, misuse by a local user and modification of important data, have been raised. In the field of anomaly-based IDS several artificial intelligence techniques are used to model normal behavior. However, there is no perfect detection method so(More)
A male one year-old beagle dog with unilateral cryptorchism was presented for investigation of reduced appetite. Abdominal sonography and radiography demonstrated abnormal enlargement of the left testicle in the abdominal cavity. Both the retroperitoneal cryptorchid testicle and the other contralateral testicle were removed surgically. The retroperitoneal(More)
As technology improves, mobile phones are becoming essential aspects of human communication. As more and more people begin to use mobile phones, various services based on mobile phone networks and high-end devices are developing. In addition, with the growth of ubiquitous computing, there have been many ongoing studies regarding novel and useful services(More)
Onion peel contains a high concentration of quercetin and other flavonoids. In this study, the potential immune-enhancing effects of an onion peel water extract (OPE) supplement were investigated by the rat forced swimming test. OPE was prepared using hot water. Thirty-six male Sprague Dawley rats were fed a pellet diet for 1 week and were then randomly(More)