• Communications for Statistical Applications and Methods
• /
• v.27 no.1
• /
• pp.15-35
• /
• 2020

In research on behavioral studies, significant attention has been paid to the stage-sequential process for multiple latent class variables. We now explore the stage-sequential process of multiple latent class variables using the multivariate latent class profile analysis (MLCPA). A latent profile variable, representing the stage-sequential process in MLCPA, is formed by a set of repeatedly measured categorical response variables. This paper proposes the extended MLCPA in order to explain an association between the latent profile variable and the latent group variable as a form of a two-dimensional contingency table. We applied the extended MLCPA to the National Longitudinal Survey on Youth 1997 (NLSY97) data to investigate the association between of developmental progression of depression and substance use behaviors among adolescents who experienced Authoritarian parental styles in their youth.

• Journal of Communications and Networks
• /
• v.5 no.3
• /
• pp.215-221
• /
• 2003

It is expected that per-user customized services are widely used in next generation Personal Communication Network. To provide personalized services for each call, per-user service profiles are frequently referenced and signaling traffic is considerably large. Since the service calls are requested from the places where user stays, we can expect that the traffic is localized. In this paper, we propose a new service profile replication scheme, named Follow-Me Replication with local Anchor (FMRA). By replicating user's service profile in a user-specific location area, local anchor of each region, the signaling traffic for call and mobility can be distributed to local network. We compared the performance of the FMRA with two typical schemes: Intelligent Network-based !Central scheme and IMT-2000 based full replication scheme, as we refer it to Follow-Me Replication Unconditional (FMRU). Performance results indicate that FMRA lies between Central and FMRU schemes according to call to mobility ratio, and we identified the efficient ranges of CMR for FMRA depending on the various network parameters.

• Communications of the Korean Institute of Information Scientists and Engineers
• /
• v.25 no.5 s.216
• /
• pp.44-52
• /
• 2007

• Journal of Multimedia Information System
• /
• v.6 no.1
• /
• pp.23-30
• /
• 2019

A communications profile is a system that acquires information from communication links to an ambulance or other vehicle moving on a road and compiles a database based on this information. The equipment (six sets of HDTVs, fish-eye camera, satellite antenna with tracking system, and receiving power from the satellite beacon of the N-star) mounted on the roof of the vehicle, image data were obtained at Yokohama Japan. From these data, the polygon of the building was actually produced and has arranged on the map of the Geographical Survey Institute of a 50 m-mesh. The optical study (relationship between visibility rate and elevation angle) were performed on actual data taken by fish-eye lens, and simulated data by 3D-Map with polygons. There was no big difference. This 3D map system then predicts the communication links that will be available at a given location. For line-of-sight communication, optical analysis allows approximation if the frequency is sufficiently high. For non-line-of-sight communication, previously obtained electric power data can be used as reference information for approximation in certain cases when combined with predicted values calculated based on a 3D map. 3D maps are more effective than 2D maps for landing emergency medical helicopters on public roadways in the event of a disaster. Using advanced imaging technologies, we have produced a semi-automatic creation of a high-precision 3D map at Yokohama Yamashita Park and vicinity and assessed its effectiveness on telecommunications and ambulatory merits.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
• /
• v.3 no.2
• /
• pp.79-83
• /
• 1992

The demand for small and low-profile antennas has become quite strong, especially in mobile communications. This article presents an brief introduction to the fundsmental characteristics, design, and measurement of typical small antennas and low-profile antennas.

• Communications of the Korean Institute of Information Scientists and Engineers
• /
• v.5 no.2
• /
• pp.85-89
• /
• 1987

The large sparse matrix problems arise in many applications areas, such as structural analysis, network analysis. In dealing with such sparse systems proper preprogramming techniques such as permuting rows and columns simultaneously, will be needed in order to reduce the number of arithmetic operations and storage spaces.

• The Journal of Society for e-Business Studies
• /
• v.18 no.2
• /
• pp.27-46
• /
• 2013

To reduce time to market for converged services, the service provider needs to combine external services and internal processes together, and IT architecture for converged services has to support it. Service Oriented Architecture (SOA) enables the development of a converged service by combining external services and internal processes effectively. However, it is difficult for the existing SOA methods to support the evolution of a converged service, even though the service which consists of the converged service changes over time. In this paper, we argue that a method for profile-based dynamic service binding is required to support evolution of converged services. In order to identify requirements for the proposed method, a business scenario with a smart athletic equipment is given. We then present the concept and architecture of the method for profile-based dynamic service binding to meet the identified requirements. We also demonstrate a prototype implementation for evaluating the proposed method.

• The Mathematical Education
• /
• v.57 no.2
• /
• pp.75-92
• /
• 2018

Based on Perceptions about Mathematics Teachers (PMT) perceived by high school students, measured by 2189 students from Seoul Educational Longitudinal Study 2014 (SELS 2014), latent profile analysis (LPA) identified five distinct types of student groups (positive, partial positive, middle, negative, extreme negative). These student of positive, middle, and negative groups are positive, moderate and negative perceptions about math teachers. Partial positive group generally had a positive perception about mathematics teachers, extremely negative group was very negative about mathematics teachers. Both of these groups had peculiarly inconsistent trends and several anomalies. The Multinomial logistic regression analyses also indicated that individual factors (gender, major, self-concept, resilience, self-assessment, career maturity), school factors (friendship, relationship with school teachers) and parental factors (academic-relationship, emotional-relationship) were significant predictors of PMT profile groups. The Analysis of variance also indicated that mathematics class (attitude, satisfaction and atmosphere), Mathematics achievement were significant predictors of PMT profile groups. The profiling of perceptions about mathematics teachers resulted in enhanced understanding of the complex range of processes students employed. During mathematics class, implementation of smooth interactions and communications between students and teachers added in the teaching and learning of mathematics.

• Communications of Mathematical Education
• /
• v.19 no.4 s.24
• /
• pp.805-822
• /
• 2005

In Korea, many local university mathematics faculty knew that the institution faced serious student shortage problems and the restructuring and cut actions for such a mathematics major programs. In general, undergraduate mathematics education in korea is in the crisis. In general, lots of mathematics departments in korea was not prepared for such a severe risk. In this article, university mathematics education and research business are studied in the context of the size of korea-usa population, economy(such as GDP), SCI indices. Korea-usa university mathematics education profile data are presented to compare korea-usa university mathematics education business. Lots of precious data on mathematics education are being helped to prepare for the university mathematics education crisis.

• Communications for Statistical Applications and Methods
• /
• v.7 no.2
• /
• pp.481-487
• /
• 2000

When we construct an interval estimate of two independent proportions with rare events, the standard approach based on the normal approximation behaves badly in many cases. The problem becomes more severe when no success observations are observed on both groups. In this paper, we compare two alternative methods of constructing a confidence interval of the difference of two independent proportions by use of simulation. One is based on the profile likelihood and the other is the Bayesian probability interval. It is shown in this paper that the Bayesian interval estimator is easy to be implemented and performs almost identical to the best frequentist's method -the profile likelihood approach.