• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2008.05a
• /
• pp.51-54
• /
• 2008

PON(Passive Optical Network) is the promising technology applicable to TPS(Triple Play Service). To improve process the packet, MAC(Multiple Access Control) is the most important technology in the PON. The core of MAC is DBA(Dynamic Bandwidth Assignment), it classifies SR-DBA(Status Report DBA) and NSR-DBA(Non Status Report DBA). But GPON DBA is using BPON's DBA, so it's bad in network efficiency. This study develop BR(Borrow-Refund)-DBA for improve network efficiency and prompt process. For take the gauge of performance evaluation, estimate about throughput, fairness and queue delay in SR-DBA and NSR-DBA environment

• The Journal of Korean Medicine
• /
• v.35 no.4
• /
• pp.52-64
• /
• 2014

Objectives: This study aimed to investigate the relationship among perceived health status, dietary habit and health promoting behaviors of university students. Methods: The subjects were 464 university students. Data were collected by using self-reported questionnaires. The results were analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient and multiple regression analysis with the PASW 18.0 program. Results: The mean score of perceived health status was 3.24, dietary habit was 2.85 and health promoting behaviors was 2.24. There were significant differences in perceived health status according to gender, BMI, exercise and stress. There were significant differences in dietary habit according to residence, monthly allowance, drinking alcohol, exercise, sleeping hours and stress. In addition there were significant differences in health promoting behaviors according to gender, residence, BMI, smoking and exercise. Also, perceived health status significantly positively correlated between dietary habit and health promoting behaviors. Conclusions: As the results of multiple regression analysis, the related factors of perceived health status of university students were exercise, stress and spiritual growth factor. Therefore, it is necessary to develop multiple health promoting programs considering characteristics of university students. And various strategies have been developed to increase the physical activity should be run.

• Journal of Multimedia Information System
• /
• v.4 no.4
• /
• pp.171-178
• /
• 2017

Data mashup is a web technology that combines information from multiple sources into a single web application. Mashup applications create a new horizon for new services, like environmental monitoring. Environmental monitoring is a serious tool for the state and private organizations, which are located in regions with environmental hazards and seek to gain insights to detect hazards and locate them clearly. These organizations utilize a data mashup to merge datasets from different Internet of multimedia things (IoMT) context-based services in order to leverage its data analytics performance and the accuracy of the predictions. However, mashup different datasets from multiple sources is a privacy hazard as it might reveal citizens specific behaviors in different regions. The ability to preserve privacy in mashuped datasets and at the same time provide accurate insights becomes a key success for the spread of mashup services. In this paper, we present our efforts to build a fog-based middleware for private data mashup (FMPM) to serve a centralized environmental monitoring service. The proposed middleware is equipped with concealment mechanisms to preserve the privacy of the merged datasets from multiple IoMT networks involved in the mashup application. Also, these mechanisms preserve the aggregates in the dataset to maximize the usability of information to attain accurate analytical results. We also provide a scenario for IoMT-enabled data mashup service and experimentation results.

• Korean Journal of Head & Neck Oncology
• /
• v.36 no.1
• /
• pp.49-52
• /
• 2020

The most common cause of primary hyperparathyroidism is a single adenoma accounts for more than 85% and about 1-2% in multiple occurrence. The adenoma arises mainly in the neck and rarely in the mediastinum. The simultaneous occurrence is extremely rare. A 73-year-old man came to our clinic complained about sense of falling forward during last eight months. The brain MRI and vestibular function test showed non-specific findings but total calcium and intact parathyroid hormone levels were markedly elevated. Radiologic studies and sesta-MIBI scan revealed multiple masses in lower paratracheal area and superior mediastinum. We performed mass excision with transcervical approach and all of them were diagnosed as parathyroid adenoma. After surgery, intact PTH and calcium levels returned to the normal range and his symptoms were dramatically improved. We report the unique and rare disease entity with a brief literature review.

• Journal of Communications and Networks
• /
• v.9 no.2
• /
• pp.159-166
• /
• 2007

In this paper, we propose an efficient and robust interference mitigation technique based on a nullsteering multi-user multiple-input multiple-output (MU-MIMO) spatial division multiple access (SDMA) scheme for frequency sharing between IMT-advanced and fixed satellite service (FSS) in the 3400-4200 and 4500-4800 MHz bands. In the proposed scheme, the pre-existing precoding matrix for SDMA unitary precoded (UPC) MIMO proposed by the authors is modified to construct nulls in the spatial spectrum corresponding to the direction angles of the victim FSS earth station (ES). Furthermore, a numerical formula to calculate the power of the interference signal received at the FSS ES when IMT-Advanced base stations (BS) are operated with the interference mitigation technique is presented. This formula can be derived in closed form and is simply implemented with the help of simulation, resulting in significantly reduced time to obtain the solution. Finally, the frequency sharing results are analyzed in the co-channel and adjacent channel with respect to minimum separation distance and direction of FSS earth station (DOE). Simulation results indicate that the proposed mitigation scheme is highly efficient in terms of reducing the separation distance as well as robust against DOE estimation errors.

• Proceedings of the IEEK Conference
• /
• 2004.06a
• /
• pp.171-174
• /
• 2004

Packet classification is an essential architectural component in implementing the quality-of-service (QoS) in today's Internet which provides a best-effort service to ail of its applications. Multiple header fields of incoming packets are compared against a set of rules in packet classification, the highest priority rule among matched rules is selected, and the packet is treated according to the action of the rule. In this Paper, we proposed a new packet classification scheme based on parallel multiple hashing on tuple spaces. Simulation results using real classifiers show that the proposed scheme provides very good performance on the required number of memory accesses and the memory size compared with previous works.

• Journal of IKEEE
• /
• v.16 no.3
• /
• pp.159-166
• /
• 2012

In this paper, we designed and implemented the MIMO (Multiple-Input Multiple-Output) antenna for the mobile handset that could be used for multiple services. Simulation results were obtained using SEMCAD X by SPEAG based on the FDTD (Finite Difference Time Domain) Method which showed that S11 values were less than -6 dB (VSWR < 3) for LTE (Long Term Evolution) 700/2300/2500, K-PCS (Korea-Personal Communication Service : 1,750 ~ 1,870 MHz), US-PCS (US-Personal Communication Service : 1,850 ~ 1,990 MHz), Wibro (2,300 ~ 2,390 MHz), Bluetooth (2,400 ~ 2,483 MHz), and US-WiMAX (US-World interoperability for Microwave Access: 2,400 ~ 2,590 MHz) frequency bands. Measured results of the fabricated antenna also showed that it could be used for LTE 700/2300/2500, K-PCS, US-PCS, Wibro, Bluetooth, and US-WiMAX. services.

• Proceedings of the IEEK Conference
• /
• 2002.07b
• /
• pp.1113-1116
• /
• 2002

For contents delivery systems, the service is considered in which the utility depends on each priority class. This paper deals with the multiple priority class of the contents delivery system from the viewpoint of the utility. The willingness to pay (WTP) is introduced as a measure of utility, and the optimum condition is analyzed to maximize the total user's utility. For the system with multiple priority classes, the optimum condition is given in terms of the traffic load, wating time for service for each priority class. Systems with the priority classes, 1, 2 and 3 are analyzed, and the effect of the number of priority classes is examined.

• Journal of the Korean Data and Information Science Society
• /
• v.19 no.4
• /
• pp.1255-1267
• /
• 2008

Evaluation indices for products or services are important to improve the internal process of the company and to compare those with competitive ones. The sigma level in Six Sigma management does important role to evaluate the core characteristic, CTQ(Critical To Quality), derived in the considered product/service or process. In this research, we propose an overall evaluation index for the product/service or process with multiple characteristics, in other words, multiple CTQs. The proposed overall evaluation index is useful for the cases that the single CTQ is not enough to evaluate the practical interests, for example, the final products and services with complex procedures and relatively large scaled processes. This approach is discussed with sigma level for applying Six Sigma Projects, however, it is applicable to indices based on proportion or percentage as well. The practical examples with a manufacturing process and a customer survey based on focus group interview are given for illustrations.

• Proceedings of the KIEE Conference
• /
• 2003.07a
• /
• pp.187-189
• /
• 2003

This paper presents new service restoration algorithm to deal with multiple faults such as main transformer fault, whole substation fault and simultaneous faults. The most important consideration of restoration planning for multiple outage areas is efficient use of redundant backup feeders. The proposed algorithm tries to restore all outage loads using outage area ordering method and tie switch exchange method that are newly proposed in this paper.