• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.5
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• pp.122-130
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• 2008

Improving the transmission rates of multi-media delivery, such as moving pictures and internet services, has become increasingly important in modern society. To satisfy such high data rate requirements, the MIMO technique, which has the capacity to transmit large amounts of data using limited frequency resources, was developed. The Space Division Multiplexing (SDM) system is one of the MIMO techniques to be able to improve the transmission capacity. However, it is unable to achieve diversity gain because of interference due to the use of multiple antennas. In this paper, an SDM system that utilizes a Multi-Block method as an advanced transmission technique in a wireless communication system to obtain diversity gain is proposed and discussed fur the performance of the proposed system.

• Clinical and Experimental Pediatrics
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• v.52 no.11
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• pp.1241-1248
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• 2009

Purpose:The etiology of Kawasaki disease (KD) is still unknown. Recently, an association between human coronavirus NL63 (HCoV-NL63) and KD was implicated. Hence, we attempted to determine the association between KD and acute respiratory viral infections. Methods:Nasopharyngeal aspirate samples were obtained from 54 patients diagnosed with KD at the Seoul National University (SNU) Children's Hospital and SNU-Bundang Hospital between October 2003 and September 2006. Viral diagnoses of 11 respiratory viruses were made using multiplex reverse transcriptase-polymerase chain reaction (RT-PCR): respiratory syncytial virus (RSV), adenovirus, rhinovirus (RV), parainfluenza viruses (PIVs) 1 and 3, influenza viruses (IFVs) A and B, human metapneumovirus (HMPV), human bocavirus (HBoV), HCoV OC43/229E, and HCoV-NL63. Clinical data were reviewed retrospectively. Results:The median age was 32 months (6 months-10.4 years). Respiratory symptoms were observed in 37 patients (69%). The following respiratory viruses were identified in 12 patients (22%): RV (n=4), PIV-3 (n=2), HBoV (n=2), and adenovirus, RSV, PIV-1, IFV-A, and HCoV-NL63 (n=1). Co-infection with PIV-3 and RV was observed in one patient. Respiratory symptoms were observed in 7 (58.3%) and 30 (71.4%) patients of the virus-positive and virus-negative groups (P>0.05). Response rate to intravenous immunoglobulin administration was 67% (n=8) and 86% (n=36) in the virus- positive and virus-negative groups (P>0.05). Conclusion:Respiratory symptoms were commonly observed in KD patients but the association between respiratory viruses and KD were not found. Large multicenter-based investigations are required to confirm the association between acute respiratory viral infections and KD.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.3
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• pp.98-109
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• 2002

Bluetooth technology is a publicly available specification proposed for Radio Frequency (RF) communication for short-range :1nd point-to-multipoint voice and data transfer. It operates in the 2.4㎓ ISM(Industrial, Scientific and Medical) band and offers the potential for low-cost, broadband wireless access for various mobile and portable devices at range of about 10 meters. In this paper, we describe the structure and the test results of the bluetooth baseband module with direct memory access method we have developed. This module consists of three blocks; link controller, UART interface, and audio CODEC. This module has a bus interface for data communication between this module and main processor and a RF interface for the transmission of bit-stream between this module and RF module. The bus interface includes DMA interface. Compared with the link controller with FIFOs, The module with DMA has a wide difference in size of module and speed of data processing. The small size module supplies lorr cost and various applications. In addition, this supports a firmware upgrade capability through UART. An FPGA and an ASIC implementation of this module, designed as soft If, are tested for file and bit-stream transfers between PCs.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.339-347
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• 2009

Purpose : This study was to investigate the influence of heart rate and coronary calcification on diagnostic accuracy of 64-slice multidetector CT(MDCT) in coronary artery disease. Methods : 178 patients(84 men, 94 women) undergoing cardiac CT were included in this study. 3 coronary arteries(LAD, LCX, RCA) were assessed the presence of significant stenosis($\geq50%$) and the results compared with those of coronary angiography. Results : On a patient-based analysis, the diagnostic accuracy of 64-slice MDCT was 96.6%. The diagnostic accuracy on left anterior descending, left circumflex, right coronary artery were 86.5%, 84.3%, 92.1% respectively. Body mass index and blood pressure were not influenced on diagnostic accuracy of 64-slice MDCT. In less than 60/min of heart rate, accuracy was 90.1% and $\kappa$ value was 0.78. While in more than 70/min of heart rate, accuracy was 75.8% and $\kappa$ value was 0.52. In less than 100 of coronary calcification, accuracy was 91.3% and $\kappa$ value was 0.81. While in more than 400, accuracy was 68.6% and $\kappa$ value was 0.33. Conclusion : 64-slice MDCT shows similar diagnostic accuracy as coronary angiography. But in the context of more than 70/min of heart rate and 400 of coronary calcification, diagnostic accuracy was decreased. So there needs to identify heart rate and coronary calcification in cardiac CT, and if heart rate shows more than 70/min, use beta-blocker to regulate it.

• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.799-806
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• 2004

A growing diversity of pervasive devices is gaming access to the Internet and other information. However, much of the rich multimedia contents cannot be easily handled by the client devices because of the limited communication, processing, storage and display capabilities. The in-tegration of voice, data and video service modified the target of networking technologies. Networks must have some the capabilities for in-tegration of various services and also for QoS support as required by each of those service. Because of these reasons, we developed EAGIS(Efficient ATM Gateway for real time Internet Service) to provide seamless multimedia service between the ATM network and the Internet. EAGIS consists of the interworking unit, content server, transcoding server, and the serveice broker to provide seamless multimedia service be-tween the ATM network and the Internet. In this paper, we design the architecture and transcoding service scenario of the EAGIS. When the RTP is used for the bi-directional communication, transcoding time is configured by the time-stamp of RTCP. When HTTP is used for unidirec-tional communication, self-timer is used. By using these reference time, standard transcoding method is applicable according to the frame trans-mission rate and network traffic load. And we can also assure the QoS of the multiple users` effective bandwidth by our algorithm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.2156-2169
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• 2012

This study was performed to find out the relationship between farmer's syndrome and self-conscious fatigue symptoms in farmers of suburban area. The questionnaire was prepared to survey the socio-demographic characteristics, health-related behaviors, farming activities, farmer's syndrome, and self-conscious fatigue symptoms of the farmers, and the survey was carried out from April 1 to June 30, 2011 by interviewing 296 farmers residing suburban area of Daejeon city. As a results, the ratio of farmers who had positive farmer's syndrome, doubtful syndrome, and no syndrome were 34.1%, 47.6%, and 18.2%, respectively. The farmer's syndrome was positively correlated with the self-conscious fatigue symptoms, and farmers with self-conscious fatigue symptoms in high risk group were at higher risk of having farmer's syndrome. The results of hierarchic multiple regression analysis indicated that sex, education, health, and self-conscious fatigue symptom were correlated with the farmer's syndrome. Among the affective factors variables, independently self-conscious fatigue symptom was the most influential. As a conclusion, the occurrence of farmer's syndrome was influenced by the socio-demographic characteristics, health-related behaviors, and self-conscious fatigue symptoms of the farmers. Especially, self-conscious fatigue symptom was independently influenced the occurrence of farmer's syndrome.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.754-761
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• 2008

As the automobile industry and technologies are developed, driver's tend to more concern about service matters than mechanical matters. For this reason, interests about recognition of human knowledge and emotion to make safe and convenient driving environment for driver are increasing more and more. recognition of human knowledge and emotion are emotion engineering technology which has been studied since the late 1980s to provide people with human-friendly services. Emotion engineering technology analyzes people's emotion through their faces, voices and gestures, so if we use this technology for automobile, we can supply drivels with various kinds of service for each driver's situation and help them drive safely. Furthermore, we can prevent accidents which are caused by careless driving or dozing off while driving by recognizing driver's gestures. the purpose of this paper is to develop a system which can recognize states of driver's emotion and attention for safe driving. First of all, we detect a signals of driver's emotion by using bio-motion signals, sleepiness and attention, and then we build several types of databases. by analyzing this databases, we find some special features about drivers' emotion, sleepiness and attention, and fuse the results through Multi-Modal method so that it is possible to develop the system.

• The KIPS Transactions:PartC
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• v.9C no.6
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• pp.935-944
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• 2002

It is the Mobile Ad Hoc Networks that constituted with serveral mobile node that can communicate with other mobile nodes. Until now, there were no routing protocols considering such as Multimediadata, VOD (Video On Demand), which is required of lots of bandwidth in Mobile Ad Hoc Network, io we are in the need of QoS (Quality of Service)routing protocol to transmit the data packets faster and more accurate. Also, there are an unidirectional links due to asymmetric property of mobile terminals or current wireless environments on practical mobile ad hoc networks. However, at present, the existing mobile ad hoc routing protocols are implemented to support only bidirectional links. In this paper, we propose the Advanced Routing routing protocol in order to implement a new routing protocol, which is fit to mobile ad hoc networks containing unidirectional links and to support QoS service. For the performance evaluation, we use NS-2 simulator of U.C. Berkeley. We could get not only increased received data rate and decreased average route discovery time, but also network load decreases with compared Best effort service.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.4
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• pp.243-252
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• 2002

To develop indicators for soil health evaluation, biological characteristics of native soils from the different parent materials were studied. Survival rate of fluorescent Pseudomonas in soils was the lowest as 0.1% while those of thermophilic Bacillus and alkaliphilic bacteria were over the 90% by the soil drying stress. There was positive relationship between soil microbial biomass and organic carbon exudated from the microbial biomass by the treatment. The average air-drying effect of soils was 39.7% with ranges of 9.7~95.0%. The propagules of mesophilic Bacillus and Gram negative bacteria were increased by the re-wetting of dried soils. Soil pH affected positively to the recovering rate of microbial number. Average recovering rate of microbes was 65.3%, and there was positive relationship between microbial biomass recovery and fluorescent Pseudomonas population.

• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.173-177
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• 2003

Purpose : Recently, different results about factors affecting accurate quantitation of 24-hr urinary protein(24UP) amount using spot urine protein/creatinine ratio(PCR) have been reported. The current study was designed to evaluate correlation between 24UP amounts and PCR in children, and the effect of 24UP amounts, age, sex, and glomerular filtration rate(GFR) on this correlation. Methods : Among 94 patients who visited the department of pediatrics in Busan Paik Hospital from March 2002 to August 2002, 68 patients whose urinary creatinine excretion was ${\geq}15mg/kg/day$ were included in this study. All the patients were divided into I, II/A, B group(I : 24UP<500 mg/day, II : $24UP{\geq}500mg/day$, A : <10 years of age, B : ${\geq}10years$ of age). Pearson correlation analysis was performed between 24UP and PCR to evaluate the relationship. We defined fractional difference between 24UP and PCR, and then performed multiple regression analysis with 24UP amount, age, GFR and fractional difference. Results : There was a strong positive linear correlation between 24UP and PCR(R=0.936, P<0.0001) in all patients, and the correlation was also good in each group. Using PCR cutoff values of 0.5, the PCR provided high sensitivity, specificity, positive and negative predictive value in predicting 24UP amount ${\geq}500mg$. The factors affecting accurate quantitation of proteinuria using spot urine PCR was age, not 24UP amount, GFR or sex. Conclusion : Spot urine PCR is a useful test but has limitations in predicting 24UP amount. Therefore, it should be used only as screening method. Age-adjusted PCR cutoff values may be necessary to predict 24UP amount in children with proteinuria.