Mobile Subscribers\u27 Willingness to Churn Under the Mobile Number Portability (MNP)

Mobile number portability (MNP) means that customers using mobile service can retain their telephone numbers when they change operators. Mobile carriers are concerned about which factors influence willingness to churn of customers. This study examined these concerns through three steps. The first is checking whether willingness to churn between the different situations, without MNP and with MNP differs. The second is to figure out how different factors influence willingness to churn in those situations. Finally, a classification model is proposed to categorize the subscribers who have willingness to churn or not. This study shows that the difference of willingness to churn before and after MNP. The results show that quality and price are the most influential factors in both cases. Inconvenience of changing numbers is additional factor in case of the unavailability of MNP. The results have implications particularly that mobile carriers should consider their quality of service and price more under the new situation

Kovalenko's Full-Rank Limit and Overhead as Lower Bounds for Error-Performances of LDPC and LT Codes over Binary Erasure Channels

We present Kovalenko's full-rank limit as a tight lower bound for decoding error probability of LDPC codes and LT codes over BEC. From the limit, we derive a full-rank overhead as a lower bound for stable overheads for successful maximum-likelihood decoding of the codes.Comment: A short version of this paper was presented at ISITA 2008, Auckland NZ. The first draft was submitted to IEEE Transactions on Information Theory, 2008/0

Unintended complication of intracranial subdural hematoma after percutaneous epidural neuroplasty.

Percutaneous epidural neuroplasty (PEN) is a known interventional technique for the management of spinal pain. As with any procedures, PEN is associated with complications ranging from mild to more serious ones. We present a case of intracranial subdural hematoma after PEN requiring surgical evacuation. We review the relevant literature and discuss possible complications of PEN and patholophysiology of intracranial subdural hematoma after PEN

Anomalous response in the vicinity of spontaneous symmetry breaking

We propose a mechanism to induce negative AC permittivity in the vicinity of a ferroelectric phase transition involved with spontaneous symmetry breaking. This mechanism makes use of responses at low frequency, yielding a high gain and a large phase delay, when the system jumps over the free-energy barrier with the aid of external fields. We illustrate the mechanism by analytically studying spin models with the Glauber-typed dynamics under periodic perturbations. Then, we show that the scenario is supported by numerical simulations of mean-field as well as two-dimensional spin systems.Comment: 6 pages, 5 figure

Cognitive Media Attributes and Motivation of IPTV for Agricultural Information

New digital media forms have broaden new business opportunities. Internet Protocol Television (IPTV) has emerged as a major contender, from these new digital media options. Agricultural and food industries are especially excited and looking forward to employing IPTV as they see it as a viable means in promoting their markets. This study examines whether the effects of media attributes and motivations affect cognitive necessity and usefulness on viewers. 254 observations of survey were collected from members of an agriculture-related web-site which shows how media attributes can impact the cognitive necessity of viewers and how motivational factors of use can influence cognitive usefulness of those viewers. From these results, IPTV service providers can obtain insight on their future programs and the proper use of their application