• Journal of Ginseng Research
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• 제9권1호
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• pp.24-35
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• 1985

Rusty root of ginseng has been known as one of the limiting factors in ginseng production in Korea. An attempt was, therefore, made to elucidate biological and chemical natures of the rusty root, and the redox Potential of the ginseng cultivated soils were measured and compared with diseased and non-diseased soils. Reddish discoloration was most frequently observed on the epidermis of ginseng root and the pigments were accumulated in all epidermal cells of the diseased lesions. The lower the redox potential of the ginseng cultivated soil was, the more severe the rusty root was observed. Fe content in the diseased epidermis was 3 times higher than that of healthy one. Organic acids such as oxalic, malonic, succinic, and citric acids were also higher in the mss root than in the healthy one. Thin layer chromatogram of phenolic acid fractions obtained from the epidermal cells of the rusty root of ginseng exhibited 3 to 4 unidentified substances not found in the healthy root. Also lignification of the epidermal cells and the activity of phenylalanine ammonia lyase were greater in the rusty root than the healthy root. Colony formation and conidia production of F. solani, And mycelial growth and sclerotium formation of Sclerotinia sp. isolated from ginseng root were suppressed in a nutritionally minimal medium supplemented with water extract of rusty ginseng root epidermis. It is, therefore, suggested that rusty root of ginseng is caused by unfavorable rhizosphere environmental stress or stresses resulting abnormal metabolism in the root as a selfdefence mechanism of non-specific resistance responses.

• Journal of Astronomy and Space Sciences
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• 제13권2호
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• pp.198-209
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• 1996

In this paper, we present an image compression algorithm that is capable of significantly reducing the vast mount of information contained in multispectral images. The developed algorithm exploits the spectral and spatial correlations found in multispectral images. The scheme encodes the difference between images after contrast/brightness equalization to remove the spectral redundancy, and utilizes a two-dimensional wavelet trans-form to remove the spatial redundancy. The transformed images are than encoded by hilbert-curve scanning and run-length-encoding, followed by huffman coding. We also present the performance of the proposed algorithm with KITSAT-1 image as well as the LANDSAT MultiSpectral Scanner data. The loss of information is evaluated by peak signal to noise ratio (PSNR) and classification capability.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권7호
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• pp.3010-3025
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• 2016

Lattice reduction (LR) has been used widely in conventional multiple-input multiple-output (MIMO) systems to enhance the performance. However, LR is hard to be applied to the relay systems which are important but more complicated in the wireless communication theory. This paper introduces a new viewpoint for utilizing LR in multiuser MIMO relay systems. The vector precoding (VP) is designed along with zero force (ZF) criterion and minimum mean square error (MMSE) criterion and enhanced by LR algorithm. This implementable precoder design combines nonlinear processing at the base station (BS) and linear processing at the relay. This precoder is capable of avoiding multiuser interference (MUI) at the mobile stations (MSs) and achieving excellent performance. Moreover, it is shown that the amount of feedback information is much less than that of the singular value decomposition (SVD) design. Simulation results show that the proposed scheme using the complex version of the Lenstra--Lenstra--Lovász (LLL) algorithm significantly improves system performance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권8호
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• pp.3054-3067
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• 2015

The phenomena of higher channel cross polarization discrimination (XPD) is mainly observed for future wireless technologies such as small cell network and massive multiple-input multiple-output (MIMO) system. Therefore, utilization of high XPD is very important and space-polarization division multiple access (SPDMA) with dual-polarized MIMO system could be a suitable solution to high-speed transmission in high XPD environment as well as reduction of array size at base station (BS). By SPDMA with dual-polarized MIMO system, two parallel data signals can be transmitted by both vertically and horizontally polarized antennas to serve different mobile stations (MSs) simultaneously compare to conventional space division multiple access (SDMA) with single-polarized MIMO system. This paper analyzes the performance of SPDMA for maximum ratio transmission (MRT) in time division duplexing (TDD) system by proposed dual-polarized MIMO spatial channel model (SCM) compare to conventional SDMA. Simulation results indicate that how SPDMA utilizes the high XPD as the number of MS increases and SPDMA performs very close to conventional SDMA for same number of antenna elements but half size of the array at BS.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권6호
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• pp.1152-1168
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• 2010

Recently, due to the prevalence of various mobile devices and wireless broadband networks, there has been a significant increase in interest and demand for multimedia streaming services such as the mobile IPTV. In such a wireless broadband network, transmitting a continuous stream of multimedia data is difficult to achieve due to mobile stations (MSs) movement. Providing Quality of Service (QoS) for multimedia video streaming applications requires the server and/or client to be network-aware and adaptive. Therefore, in order to deploy a mobile IPTV service in wireless broadband networks, offering users efficient wireless resource utilization and seamlessly offering user perceived QoS are important issues. In this paper, we propose a new adaptive streaming scheme, called MARC (Mobile-aware Adaptive Rate Control), which adjusts the quality of bit-stream and transmission rate of video streaming based on the wireless channel status and network status. The proposed scheme can control the rate of multimedia streaming to be suitable for the wireless channel status by using awareness information of the wireless channel quality and the mobile station location. The proposed scheme can provide a seamless multimedia playback service in wireless broadband networks in addition to improving the QoS of multimedia streaming services. The proposed MARC scheme alleviates the discontinuity of multimedia playback and allocates a suitable client buffer to the wireless broadband network. The simulation results demonstrate the effectiveness of our proposed scheme.

• The Korean Journal of Health Service Management
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• 제9권4호
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• pp.63-78
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• 2015

Objectives : The aim of this study was to examine how emergency medical technicians(EMT) are affected by job stress, musculoskeletal symptoms(MSSs) and depression. Methods : Data were collected from EMTs at emergency medical institutions and fire stations (n=257). With a questionnaire, the association of job stress and MSSs and depression were examined in this study. Results : When examining job stress by place of work, the level of stress in field situations was significantly higher in EMTs at fire stations than in EMTs at emergency medical institutions. The MSSs of EMTs at emergency medical institutions were significantly higher compared to EMTs at fire stations, For depression, the score was 14.09 out of 60, and MSSs were significantly more common in women. Additionally, the level of job stress for 20-24 and over 35 year olds was significantly higher than that in the other age groups. Job stress had a positive correlation with MSSs and depression of EMTs, and MSSs were associated with depression. Conclusions : To improve the work environment of EMTs, attention should be paid to job stress, MSS, and depression and the presence of positive organizational support should be provided which can prevent negative effects.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제36권5C호
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• pp.326-335
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• 2011

In this paper, we evaluate the performance of multi-antenna techniques adopted for the IEEE 802.16m standard. Base station is equipped with 4 or 8 antennas, and each mobile station (MS) has 2, 4, 8 antennas. The number of MSs is 4, and MIMO modes 0, 1, and 4 are evaluated. For each mimo mode, various number of data streams can be implemented, and the selected number of streams in the paper corresponds to the parameters adopted for hardware implementation. The error performance of various mimo modes presented in this paper was used as reference performance to verify successful hardware implementation.

• Proceedings of the Korea Information Processing Society Conference
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• 한국정보처리학회 2000년도 추계학술발표논문집 (하)
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• pp.1353-1356
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• 2000

최근 B2B 시스템 통합 및 전략적 제휴가 시장을 변화시키고 있고 관련 기업들의 효율적인 연계요구가 증가됨에 따라 기업간 시스템들의 연동이 중요한 문제로 부각되고 있다. 워크플로우 표준화 단체인 WfMC 에서도 이러한 문제 해결의 일환으로 인터넷을 통한 워크플로우 관리 시스템간 연동을 위한 표준인 Wf-XML Interoperability standard 를 발표하였다. 본 논문은 Wf-XML 표준 및 관련 연구들을 조사하고 WfMC 표준에는 정의되어 있지 않으나 시스템간의 신뢰성있는 연동을 위해 고려할 사항 중에서 동기적 및 비동기적 상호연동을 위한 요구사항들을 분석한다. TCP/IP 를 기반으로 한 HTTP 프로토콜을 전송 프로토콜로 채택하는 경우 여러 오퍼레이션들을 일괄처리하기 위해서는 비동기적인 상호연동(asynchronous interoperation)을 위한 별도의 메커니즘이 필요하다. 본 연구에서는 Wf-XML 문서를 HTTP 프로토콜을 사용하여 전송하는 경우 일괄처리요청(batch request) 및 그 밖의 동기적 또는 비동기적 요청들을 처리하기 위한 상호연동 모델을 분석하고 분산 워크플로우 시스템의 일종인 ICU/COWS에서의 적용방안에 관해서 논의한다.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2655-2660
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• 2009

A breed of cattle, i.e., Korean cattle (Hanwoo), was identified based on the DNA mobilities of their microsatellites (MSs) by capillary gel electrophoresis (CGE) with a laser-induced fluorescence (LIF) detector. The MS markers were used for the accurate identification of species-specific genes. The DNA mobilities of the MS markers of Hanwoo and Holstein were measured using a CGE system with a fused-silica capillary (inner diameter of 75 ${\mu}m$, outer diameter of 365 ${\mu}m$, and total length of 50 cm). The capillary was dynamically coated with 1.0% (w/v) polyvinylpyrrolidone ($M_r$ = 1,000,000) and then filled with a mixture of 1.3% (w/v) poly(ethylene oxide) ($M_r$ = 600,000) and 1.9% (w/v) poly(ethylene oxide) (Mr = 8,000,000) as a sieving gel matrix. The species-specific genes of Hanwoo and Holstein were clearly distinguished within 33 min. This CGE assay technique is expected to be a useful analytical method for the fast and accurate identification of breeds of cattle.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제41권10호
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• pp.1186-1189
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• 2016

A distributed uplink power control algorithm based on flocking model is proposed to improve the energy efficiency of mobiles station (MS) in cellular networks. As each bird in a flock matches its velocity with the average velocity of the adjacent birds, each MS in a cell matches its uplink rate with the average uplink rate of the co-channel MSs in adjacent cells by controlling its transmission power. Results show that the proposed algorithm effectively reduces the power consumption in the MS, while maintaining a low outage probability, which eventually improves the energy efficiency of the MS.