• Journal of the East Asian Society of Dietary Life
• /
• v.15 no.3
• /
• pp.257-263
• /
• 2005

In this study, lotus root(Nelumbo nucifera G.) which has been used in oriental medicine and folks remedy, was studied to apply to functional foods. We investigated the effects of the lotus root extracts(LTE) with hot water on the reduction of serum lipid and improvement of blood parameters in rats fed high fat diet for 5 weeks. Sprague-Dawley rats weigh $150g\pm15g$, were randomly assigned to 4 groups such as basal diet only(BDG), high fat diet without LTE(FDCG), high fat diet with $6\%$ LTE(FD6L), high fat diet with $12\%$ LTE(FD12L). The results of this study were as follows. Hematological data were not significantly different among 4 groups. Serum transferrin concentration and GOT activity were reasonable levels in FD6L and FD12L groups compared with FDCG group. Total cholesterol, LDL-cholesterol, triglyceride in serum and atherogenic index were remarkably reduced in LTE supplemented groups as compared with the control group. But HDL-cholesterol contents in FD6L and FD12L groups were significantly increased compared with that in control group. These results imply that lotus root extracts could be used as a potent food resources for decrease of serum lipid concentration.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.27 no.5
• /
• pp.445-453
• /
• 2016

This paper presents the implementation and design of the 1T-1R wireless HD video streaming systems over 28 GHz mmWave frequency using 3GPP LTE-TDD standard on NI USRP RIO SDR platform. The baseband of the system uses USRP RIO that are stored in Xilinx Kintex-7 chip to implement LTE-TDD transceiver modem, the signal that are transceived from USRP RIO up or down converts to 28 GHz by using self-designed 28 GHz RF transceiver modules and it is finally communicated HD video data through self-designed $4{\times}8$ sub array antennas. It is that communication method between USRP RIO and Host PC use PCI express ${\times}4$ to minimize delay of data to transmit and receive. The implemented system show high error vector magnitude performance above 25.85 dBc and to transceive HD video in experiment environment anywhere.

• Asian Journal of Innovation and Policy
• /
• v.2 no.2
• /
• pp.150-172
• /
• 2013

This paper wanted to find out research trends and its determinants on mobile commerce research reviewing 439 articles from 1999, the starting year of this field to 2012. Our analytical framework has 4 categories such as general, technology, consumer and firm, and 14 sub-categories. The results are as follows: First, studies on mobile commerce can be divided into 5 stages. Second, trends of mobile commerce are closely related to the evolution of mobile technologies such as communication technologies and devices (2G, 3G, 3G+, 4G LTE, LTE-A). Third, this field was led by USA until 2005 and has been led by Taiwan after 2006. Fourth, China, Korea, UK and Canada are also leading countries, all of which have mobile device manufacturers. Research trends of non-manufacturing countries and manufacturing countries are different from each other. In addition, the trends of leading countries are different from each other reflecting each country's business needs.

• Journal of IKEEE
• /
• v.27 no.4
• /
• pp.617-623
• /
• 2023

With the evolution of communication networks, there is a growing demand for stable high-speed data connections to support services relying on large-capacity data. The increasing volume of packet data aggregated from user devices underscores the significance of quality diagnostics for the backhaul network, an intermediate link transmitting data to the core network. This paper conducts empirical research on techniques to diagnose issues within the backhaul network through practical case studies, through diagnosing various factors such as circuit bandwidth, speed disparities within switches, network segment-specific buffer sizes, routing policies, among other factors that could potentially cause RTT (Round Trip Time) delays and performance degradation.

• Journal of Korea Society of Industrial Information Systems
• /
• v.17 no.1
• /
• pp.31-38
• /
• 2012

Next generation cellular applications and smart phone usage generate very heavy wireless data traffic. It becomes ineluctable for mobile network operators to have multiple core network entities such as Serving Gateway and Packet Data Network Gateway in 4G-LTE to share this high traffic generated. A typical configuration consists of multiple serving gateways behind a load-balancer which would determine which serving gateway would service a end-users'request. Such hardware is expensive, has a rigid policy set, and is a single point of failure. Another perspective of today's increasingly high data traffic is that besides it is being widely accepted that the high bandwidth L TE provides is creating bottlenecks for service providers by the increasing user bandwidth demands without creating any corresponding revenue improvements, a hidden problem that is also passively advancing on the newly emerging 4G-LTE that may need more immediate attention is the network signaling traffic, also known as the control-plane traffic that is generated by the applications developed for smartphones and tablets. With this as starting point, in this paper, we propose a solution, by a new approach considering OpenFlow switch connected to a controller, which gains flexibility in policy, costs less, and has the potential to be more robust to failure with future generations of switches. This also solves the problem of scaling the control-plane traffic that is imperative to preserve revenue and ensure customer satisfaction. Thus, with the proposed architecture with OpenFlow, mobile network operators could manipulate the traffic generated by the control-plane signaling separated from the data-plane, besides also reducing the cost in installing multiple core-network entities.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.6
• /
• pp.15-23
• /
• 2016

In this paper we presented 4G security models in an open environment. 4G networks have still more security holes and open issues for expert to notice. In here. we show that a number of new security threats to cause unexpected service interruption and disclosure of information will be possible in 4G due mainly to the fact that 4G is an IP-based, heterogeneous network. it tells about the security issues and vulnerabilities present in the above 4G standards.. we try to present several architectures behind 4G infrastructure for example WiMAX and 3GPP LTE architecture. Finally, we point to potential areas for future vulnerabilities and evaluate areas in 4G security which warrant attention. When you make a big dada program, If you use this network architecture then you can improve your learning speed.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.1
• /
• pp.127-134
• /
• 2022

A modified folded monopole slot antenna for 3G WCDMA (1.91 ~ 2.17 GHz), 4G LTE (2.17 ~ 2.67 GHz), 3.5 GHz 5G (3.42 ~ 3.7 GHz) and Wi-Fi dual band (2.4 ~ 2.484 GHz / 5.15 ~ 5.825 GHz) was proposed for the first time. The proposed antenna is designed and fabricated on a FR-4 substrate with dielectric constant 4.3, thickness of 1.6 mm, and size of 35 × 60 mm². The measured impedance bandwidth of the proposed antenna is 2910 MHz(1.84 ~ 4.75 GHz) and 930 MHz(5.11 ~ 6.04 GHz), antenna gain in each frequency band is from 1.811 to 3.450 dBi. In particular, it was possible to obtain a commercially suitable omni-directional radiation pattern in all frequency bands of interest.

• Journal of IKEEE
• /
• v.24 no.1
• /
• pp.90-96
• /
• 2020

As various communication services have emerged due to the development of mobile communication technology, there is a need for a wideband antenna supporting multiple communication services with one antenna. In this paper, we propose a planar slot wideband antenna that can support all the communication services of 3.1~4.99GHz, the low frequency band of 5G, in addition to the existing communication services such as WiFi, LTE 2300/2500, and WiMAX. Through the simulation, the optimized antenna design parameters were obtained, and the antenna was fabricated to implement an antenna with a frequency bandwidth of 1.96~6.01GHz (S11 <-10dB) and presented the radiation pattern and gain of the antenna. The proposed antenna is a multi-band antenna that can provide all the services of LTE, Wifi, WiMAX, and 5G low frequency bands. It can be used as a repeater antenna in radio shadow area such as buildings, dense areas, and ships.

• Journal of Internet Computing and Services
• /
• v.18 no.4
• /
• pp.27-34
• /
• 2017

In this paper, the analysis of mobile augmented reality service using 5G network are provided. First of all, the introduction and required performance of mobile augmented reality(MAr) service are provided. After that, 5G network key features, target performance, and network architecture are analyzed. At the end, the additional network entity and functions for the realization of mobile augmented reality service are proposed. The mobile augmented reality service time. At the end, the service delay in existing LTE system and proposed 5G MAr system by using real device and network parameters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2013.10a
• /
• pp.146-149
• /
• 2013

For in recently years, global cellular network service is changing rapidly to 4G. However, the fast introducing of 4G has been going with not enough research about security threat, it could be many kind of vulnerability. Therefore the research about security threat on 4G network is ongoing in external countries, but not sufficient in domestic. particularly in domestic situation of rapidly increased subscribers, The security threats which are hindering stability and usability could make a fatal effect on many users. 4G network should be considered about the feature of mobile network to protect 4G network stable. Mobile network has limited radio resources, it releases the radio resource which is not used in selected time and reallocate when detected the data transmission. Many signaling messages are transferred in the network entities to allocate or release the radio resource. In this paper, it will be introduced the technology to detect signaling DoS traffic hindering the stability and usability of network entities managing the radio resources by huge signaling message from the repetitive wireless connection/release message.