• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.4
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• pp.929-935
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• 2008

As internet telephony services based on Session initiation Protocol (SIP) enter the spotlight as marketable technology, many products based on SIPs have been developed and utilized for home and office telephony services. The call connection of an internet phone is classified into specific call connections and group call connections. Group call connections have a forking function which delivers the message to all of the group members. This function requires excessive message control for a call connection and creates heavy traffic in the network. In the internet cail system model. most of the call-setup messages are directed to the proxy server during a short time period. This heavy message load brings an unwanted delay in message processing and. as a result, call setup can not be made. To solve the delay problem, we simplified the analysis of the call-setup message in the proxy server, and processed the forking function distributed for the group call-setup message. In this thesis, a new system model to minimize the load is proposed and the subsequent implementation of this model demonstrates the performance improvement.

• Journal of Convergence Society for SMB
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• v.2 no.2
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• pp.1-6
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• 2012

In this paper, we propose a detector generation model which is applied to immune system to improve the misuse detection rates in misuse detection models. 10cv method is used to sendmail data which is provided by the DARPA. We experimented and analyzed the misuse detection rate that is either judgment of the normal system call as abnormal system call or judgment of the abnormal system call as normal system call. In the experiment, between detector which was generated by any abnormal system call and temporary detector. I did experiments with a new detector which was removed temporary detector which made a wrong decision for normal system call as an abnormal system call and abnormal system call as a normal system call. The misuse detection rate of detector which is applied to the immune system is greater than the other detector by 0.3%.

• Journal of Ecology and Environment
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• v.31 no.1
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• pp.69-73
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• 2008

We studied the functional roles of two types of calls, mew calls and mobbing calls, of the black-tailed gull (Larus crassirostris) by examining responses of mixed flocks of gulls to the playback calls. Playback experiments were conducted on four days between 11 May and 5 June 2007 at 16 sites in Sinjindo-ri and Dowhang-ri, Taean-gun, Chungnam province and Imjado, Sinan-gun, Jeonnam province, South Korea. We examined the anti-predator responses of the gulls to the playback trials. We found that gull flocks initially responded to mew call playbacks by mobbing in less than half of playback trials (6/14) while all trials involving playbacks of the mobbing call and control (group mobbing) call evoked mobbing. When trials in which no response was recorded were excluded, we found that the gulls' responses to mobbing and group mobbing call playbacks was more intense than their response to mew call playbacks, in that gulls mobbed longer, more gulls responded, and gulls took flight after a shorter time interval. However, the intensity of the gulls' response did not differ in mobbing call and group mobbing call playbacks. The results of this study suggest that the mixed-species flocks of gulls discriminate between the mew calls and the mobbing calls.

• Journal of Korea Multimedia Society
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• v.11 no.7
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• pp.1016-1024
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• 2008

In this paper, we designed and implemented the ACE(ACtive Emergency call service system) system for emergency call service actively. ACE system has two physical components; E-Device(Emergency Mobile Device) and E-Server(Emergency Server). The role of E-Device is the mobile device in order to call emergency by using mild handi-capped, the elderly and children who are able to communicate theirs intention to another. E-Server is the server for management E-devices with realtime monitering. E-Device will be developed to the portable size for easily mild handi-capped, the elderly and children. When they need the service of emergency call, the button of E-device can be used and the call signal is transmitted to the emergency office and the guardian through Internet and CDMA. E-server should be developed the integrated control system for management of E-Devices basically. And it also supported to realtime monitoring of E-devices with respect to high quality of emergency call service for rise the efficiency.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.121-126
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• 2019

This experiment was conducted to breed a very early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan 2015-2017. The new variety of Italian ryegrass, 'Green call 2ho' is a diploid variety with green in leaf color and has semi-erect growth habit in late autumn and erect growth habit in early spring, 'Green call 2ho' was in heading date as a early-maturing variety April 24. Also 'Green call 2ho' was narrower by 2 mm in flag leaf width, longer by 2.5 cm in flag leaf length and shorter by 3 cm in plant height than those of the control variety, 'Florida 80', respectively. 'Green call 2ho' was also thicker by 0.33 mm in stem thickness and strong in winter hardness. Dry matter (DM) yield (11,688 kg/ha) of 'Green call 2ho' was 7% higher than that of 'Florida 80'. Total digestible nutrient (TDN), crude protein (CP) and relative feed value (RFV) of 'Green call 2ho' were 61.3 %, 9.8 % and 98.2, respectively which are 2.6, 0.6, and 8.4 % higher, respectively than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green call 2ho' were 34.9 and 58.5 % which are 3.3 and 2.7 % lower than those of 'Florida 80', respectively.

• Journal of the Korea Society of Computer and Information
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• v.28 no.10
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• pp.155-161
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• 2023

In this paper, we present a WebRTC-based emergency video call system structure that builds a service system in a constant monitoring environment to increase the usability and stability of elevator emergency call devices. The proposed system provides a smooth call environment between the emergency call system in the elevator and maintenance managers in case of an emergency, performs rapid response processing to elevator emergency calls through monitoring of the target elevator, and handles any emergency calls that may occur in the physical space of the elevator. The purpose is to build an environment that can implement low-latency, real-time video call services of voice and video by overcoming the physical constraints required for video calls. To this end, we have established a service environment based on OpenAPI, which is currently used in various fields and its performance has been proven, and provides video calls and emergency situation dissemination through rapid messaging by providing low-latency call quality. The presented system structure will be able to provide a basis for expanding various functions and constructing a reliable service environment and intelligent model for the elevator system through combination with the elevator control panel and various devices.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.2
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• pp.31-39
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• 1998

In this paper, we have presented a quantitative performance effect of CCP(Call Control Processor) when SAAL(Signalling ATM Adaptation Layer) function is distributed from CCP to SIMs(Subscriber Interface Modules) in an ATM switching system with distributed architecutre. For the performance analysis, SLAM II simulation language is used and subscriber signalling messageand inter-processor communication messages according to Q.2931 based local call processing procedure are taken into consideration in the proposed queuing network model. The results of simulation are compared with in case of processing SAAL function on CCP. It is observed that the processing utilization of CCP reach 24,000 BHCA and 25,700 BHCAwhen SAAL function load amounts to 10% and 20% of the processing time of the total message, respectively. These values shows that the processing utilization of CCP is alleviated about 7% in comparison with 2,000 BHCA in case that SAAL function is carried out on CCP. Consquently, it is shown that we have to consider seriously how to distribute the functions concerning call processing in a large cale ATM switching system architecture accomodating a number of SIMs.

• The Journal of the Acoustical Society of Korea
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• v.21 no.1
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• pp.27-36
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• 2002

VoiceXML is a standard dialog mark-up language for the neat generation voice applications. The current VoiceXML 1.0 specification is silent on who place outbound calls for push-based voice applications. The push-barred voice applications become very important in modern information systems such as CRM. In this paper, we design and implement an extended VoiceXML platform that supports both inbound and outbound voice information services. We also extend the VoiceXML DTD so as to be able to inbound/outbound fax based on Call Control Requirements of W3C.

• Journal of Advanced Navigation Technology
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• v.12 no.1
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• pp.22-27
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• 2008

This paper presents adaptive-MMOSPRED method for prediction of resource demands requested by multimedia calls, and shows the performance of the call admission control based on proposed resource prediction method in multimedia wireless networks. The proposed method determines (I-CDP) random variables of the standard normal distribution by using LMS algorithm that minimize errors of prediction in resource demands, while parameters in an existing method are constant all through the prediction time. Our simulation results show that prediction error in adaptive-MMOSPRED method is much smaller than in fixed-MMOSPRED method. Also we can see via simulation the CAC performance based on the proposed method improves the new call blocking performance compared with the existing method under the desired handoff dropping probability.

• International journal of advanced smart convergence
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• v.1 no.1
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• pp.19-26
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• 2012

The deployment of mobile femtocellular networks can enhance the service quality for the users inside the vehicles. The deployment of mobile femtocells generates a lot of handover calls. Also, numbers of group handover scenarios are found in mobile femtocellular network deployment. The ability to seamlessly switch between the femtocells and the macrocell networks is a key concern for femtocell network deployment. However, until now there is no effective and complete handover scheme for the mobile femtocell network deployment. Also handover between the backhaul networks is a major concern for the mobile femtocellular network deployment. In this paper, we propose handover control between the access networks for the individual handover cases. Call flows for the handover between the backhaul networks of the macrocell-to-macrocell case are proposed in this paper. We also propose the link switching for the FSO based backhaul networks. The proposed resource allocation scheme ensures the negligible handover call dropping probability as well as higher bandwidth utilization.