• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.76-84
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• 2013

In the passive emitter localization using instantaneous TDOA (time difference of arrival) and FDOA (frequency difference of arrival) measurements, the estimation accuracy can be improved by collecting additional measurements. To achieve this goal, it is required to increase the number of the sensors. However, in electronic warfare environment, a large number of sensors cause the loss of military strength due to high probability of intercept. Also, the additional processes should be considered such as the data link and the clock synchronization between the sensors. Hence, in this paper, the passive localization of a stationary emitter is presented by using the successive TDOA and FDOA measurements from two moving sensors. In this case, since an independent pair of sensors is added in the data set at every instant of measurement, each pair of sensors does not share the common reference sensor. Therefore, the QCLS (quadratic correction least squares) methods cannot be applied, in which all pairs of sensor should include the common reference sensor. For this reason, a Gauss-Newton algorithm is adopted to solve the non-linear least square problem. In addition, to show the performance of the proposed method, we compare the RMSE (root mean square error) of the estimates with CRLB (Cramer-Rao lower bound) and derived the CEP (circular error probable) planes to analyze the expected estimation performance on the 2-dimensional space.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.2 no.1 s.2
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• pp.15-24
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• 2003

While public institutions and privite coperations have constructed the data collecting infrastructure and commercialized it to service traffic information, inaccuracy with information, insufficiency with the public sector, overapping investment and the rest are arising from the differences of data treatment, offering method, communication protocal and the like. For these reasons, we need standardization it as a national enterprise. In this paper, we would like to present the unity management and joint method of traffic information based on the present position of system construction and national ITS standardization. At first, we presented the relation between data elements and message sets and then analyzed how message sets have been used to message sets to share traffic information so far in public institutions and private coperations like Korea freeway cooperation-ITS model city-Cheonan-Nonsan expressway, In-cheon international airport expressway-Korea freeway cooperation and Seoul metropolitan police agency-Seoul metropolitan government. As the results of analyzing message sets, it had disclosed that data transmission is impossible or a system is unchangeable because data form and each items to transmission were different from each other and its own address and link IDS were not determined yet. Also it showed these message sets did not abidy by The Draft of National ITS Standards. First of all, we proposed data basic form and elements which were form by items used in each center in common and the elements to manage traffic information suggested by Standards based on the results of analyses.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.12
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• pp.1250-1260
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• 2014

In this paper, a novel resource scheduling, which is used for hub network based long distance airborne tactical communication, is proposed. Recently, some countries of the world has concentrated on developing data rate and networking performance of CDL, striving to keep pace with modern warfare, which is changed into NCW. And our government has also developed the next generation high capacity CDL. In hub network, a typical communication structure of CDL, hybrid FDMA/TDMA can be considered to exchange high rate data among multiple UAVs simultaneously, within limited bandwidth. However, due to different RTT and traffic size of UAV, idle time resource and unnecessary packet transmission delay can occur. And these losses can reduce entire efficiency of hub network in long distance communication. Therefore, in this paper, we propose RTT and data traffic size based UAV scheduling, which selects time/frequency resource of UAVs by using iterative sorting algorithm. The simulation results verified that the proposed scheme improves data rate and packet delay performance in low complexity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.249-257
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• 2017

Filtering the data for travel time records obtained from DSRC probes is essential for a better estimation of the link travel time. This study addresses the major deficiency in the performance of TRANSGUIDE in removing anomalous data. This algorithm is unable to handle unstable traffic flow conditions for certain time intervals, where fluctuations are observed. In this regard, this study proposes an algorithm that is capable of overcoming the weaknesses of TRANSGUIDE. If TRANSGUIDE fails to validate sufficient number of observations inside one time interval, another process specifies a new validity range based on the median absolute deviation (MAD), a common statistical approach. The proposed algorithm suggests the parameters, ${\alpha}$ and ${\beta}$, to consider the maximum allowed outlier within a one-time interval to respond to certain traffic flow conditions. The parameter estimation relies on historical data because it needs to be updated frequently. To test the proposed algorithm, the DSRC probe travel time data were collected from a multilane highway road section. Calibration of the model was performed by statistical data analysis through using cumulative relative frequency. The qualitative evaluation shows satisfactory performance. The proposed model overcomes the deficiency associated with the rapid change in travel time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.4
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• pp.666-677
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• 2015

The importance of application traffic analysis for efficient network management has been emphasized continuously. Snort is a popular traffic analysis system which detects traffic matched to pre-defined signatures and perform various actions based on the rules. However, it is very difficult to get highly accurate signatures to meet various analysis purpose because it is very tedious and time-consuming work to search the entire traffic data manually or semi-automatically. In this paper, we propose a novel method to generate signatures in a fully automatic manner in the form of sort rule from raw packet data captured from network link or end-host. We use a sequence pattern algorithm to generate common substring satisfying the minimum support from traffic flow data. Also, we extract the location and header information of the signature which are the components of snort content rule. When we analyzed the proposed method to several application traffic data, the generated rule could detect more than 97 percentage of the traffic data.

• Journal of the Korean Society for information Management
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• v.24 no.4
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• pp.73-96
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• 2007

In this study, the characteristics of scholarly communication through the Web and scientific journals are explored, and scholarly communication patterns in two scientific disciplines are compared to reveal the difference. Economics and Computer Science-Information Systems are selected as two disciplines to be analyzed. In the data collection process, 10 keywords are extracted from a database for each subject field, and scholarly Web pages and journal articles related to these keywords are collected and analyzed. Our investigation includes the characteristics of scholarly Web pages, Multi-Dimensional Scaling (MDS) analysis of co-linked Web pages as well as co-cited journal articles, and changes in the scholarly communication activities occurring on the Web and in scientific journals respectively over time. We found certain differences as well as common features in scholarly communication patterns between the Web and scientific journals for both fields of Economics and Computer Science. We also found that scholarly communication occurring on the Web displays unique features for each subtopic within the same field of study.

• Journal of East-West Nursing Research
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• v.20 no.2
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• pp.93-102
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• 2014

Purpose: This study aimed to investigate the characteristics of patients attempting suicide and to analyze treatment determination factors for patients with mental illness who go to an emergency center for treatment. Methods: Data collected from 117 suicide attempters who visited Busan Regional Emergency Medical Center were analyzed using frequency, percentage, ${\chi}^2$-test with SPSS/WIN 15.0. Results: Only 31 cases consulted with the psychiatric department; the other attempters' refused to consult (26.5%). Among the 31 attempters who consulted, 23 cases (74.2%) were suffering from depression. The most common reason (38.6%) suicidal attempters gave to refuse psychiatric treatment was "I'm not mad. I don't need the psychiatric treatment". Treatment determination factors for mental illness were religion (p<.001), past history (p=.017), financial satisfaction (p=.048), previous history of suicidal attempts (p=.006), sleep disturbance (p<.001), expression of suicide (p=.010), and type of leaving the emergency room (p=.020, p<.001). Conclusion: Results suggest that people frequently misunderstand psychiatric treatment which leads to their refusal to accept psychiatric treatment. Therefore hospitals need to develop standard guidelines and procedures for suicidal attempters with the collaboration of emergency and psychiatry departments. In addition, medical teams need to provide attempters appropriate information and encourage them to actively seek psychiatric treatment.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.4
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• pp.10-21
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• 2003

Recently, the optical subscriber interface module uses the high performance network processor to quickly develop new application services such as MPLS, VPN, RPR and EPON with a short time-to-market. Although a number of vendors are developing the network processor at 2.5Gbps, only the IBM NP4GS3 can provide packet processing with wire-speed at 2.5Gbps. IBM NP4GS3, however, uses its unique speed DASL interface instead of CSIX-Ll interface, which has standardized by M: Forum currently Therefore, we implement an interconnection mechanism to use the switch fabric with CSIX-Ll interface. In this paper, we suggest the architecture and a packet control mechanism supporting interconnection between IBM NP4GS3 DASL and CSIX-Ll switch interface using the common IBM UDASL ASIC and XILINX FPGA.

• Journal of the Korean Geotechnical Society
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• v.21 no.2
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• pp.37-46
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• 2005

In the field of earthquake engineering, recent improvements in many areas, such as seismological source modeling, analysis of travel path effects, and characterization of local site effects on strong shaking, have led to significant advances in both code-based and more advanced procedures for evaluating earthquake ground motions. A missing link, however, is empirically verified design procedures fur assessing the effects of soil-structure interaction (SSI). Available Soil-Structure Interaction (SSI) analysis techniques range from simple substructure-type procedures to relatively sophisticated finite element procedures. The most common substructure approach for foundation-soil interaction is to use a frequency-dependent and complex-valued impedance function. This study uniquely evaluates impedance functions for two well-instrumented sites w significant inertial SSI effects using a system Identification technique. The system identification analysis results are then compared to predictions from a simple theoretical model to gain insight into the inertial interaction effect in the subject sites.

• Journal of Family Resource Management and Policy Review
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• v.18 no.1
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• pp.1-28
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• 2014

The purpose of this study is to suggest how the first birthday rite, a practice in Korean culture, has changed over the time. A survey of 250 mothers was undertaken from October 11th to November 6th, 2012. The research questions asked in this study are as follows. What general and expert views are held about the first birthday rite? What type of awareness and knowledge do mothers have about the first birthday rite? Is there any correlation between mothers' awareness and knowledge about first birthday rite? What is the importance of the components of the baby's first birthday rite and the importance of choosing first birthday rite goods? The data were analyzed using SPSS 17.0. Frequency, F-test, correlation were also employed. The results of this study are as follows: The first birthday rite shows a clear link to socializing. It is a family event, but is also seen as an opportunity to enhance relationships with relatives, colleagues, and friends. A banquet hall is chosen as preferred first birthday rite location, and participants are served a meal and receive gifts. The banquet information on first birthday rites was initially collected from the internet, blog cafes, and an experienced. However, it has become gradually more common to hire a consultant to organize the first birthday rite. Awareness of the first birthday rite is high, but knowledge is relatively low. In addition, there is a positive relationship between awareness and knowledge about the first birthday rite. When mothers are preparing for their baby's first birthday, they consider food for the guests' banquet, space and time. Finally, individual positive relationships were found between choosing first birthday rite goods and employee services, contract pricing for goods, and food for guests.