• Title/Summary/Keyword: common channel

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A Simple Multi-rate Parallel Interference Canceller for the IMT-2000 3GPP System (IMT-2000 3GPP 시스템을 위한 간단한 다중 전송률 병렬형 간섭제거기)

  • Kim, Jin-Kyeom;Oh, Seong-Keun;Sunwoo, Myung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.12
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    • pp.10-19
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    • 2001
  • In this paper, we propose an effective but simple multi-rate parallel interference canceller(PIC) for the international mobile telecommunications-2000(IMT-2000) 3rd generation partnership project (3GPP) system. For effective multi-rate processing, we define the basic block as one symbol period of the dedicated physical control channel(DPCCH) having the lowest data rate and common to all users. Then, decision and interference cancellation are performed at every basic block. For an asynchronous channel, we propose an advance removal scheme that removes in advance multiple access interference(MAI) due to the next blockof other users with shorter delay. Introducing a pipeline structure at a sample base, we can implement efficiently the PIC using the advance removal scheme with a minimum hardware and no extra computations. Through computer simulations, we analyze the bit error rate(BER) performance of the proposed PIC with respect to signal-to-noise ratio(SNR) and the number of users.

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A study on the Physiology of the Lung by 'Un Qi' and the clinical meaning of its Phyological Systems (폐장생리(肺臟生理)의 운기적(運氣的) 인식과 그 생리계통(生理系統)의 임상적 의의에 관한 연구(硏究))

  • Shin, Heung-Mook;Kim, Gil-Whon
    • The Journal of Korean Medicine
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    • v.18 no.2
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    • pp.5-14
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    • 1997
  • This paper documents a study of the physiology of the lung. The aim of this paper is to better comprehend the physiological function of lung. To this end, the relationship between the physiological function of the lung and the characteristics of the 'Keum Un Qi Hua'(金運氣化), and the functional changes of the lung and its surrounding physiological systems have been studied in their relationship to the concept of the organism as a whole. The results of this study are as follows; The function of the lung is comprehended as corresponding to the 'Keum Un Qi Hua'. In visceral phenomenon, the lung has specific relations with the large intestine(大腸), nase(鼻), skin and hair(皮毛), sweat gland(汗孔), nasal mucus(涕), spirit(氣魄), grief and melancholy(憂 悲), the lung channel of hand-taiyin(手太陰肺經), the large intestine channel of hand-yangming(手陽明大腸經). This is called ‘the physiological systems of the lung’, and because these mutual relations reflect the functional changes of the lung, it is applied as the elementary knowledge to diagnose and treat the lung. For instance, a deficiency of the 'Qi‘ of the lung brings on an unconsolidated defending energy whose manifestations are sweating spontaneously as well as being susceptible to the common cold due to a diability in fighting against external pathogenic factors. Invasion of the lung by external pathogenic factors blocks the movement of the 'Qi' of the lung, which results in nasal obstraction. watery nasal discharge and a hyposmia. So the physiological functions and pathological changes of the lung can be determined by observing ’the physiological systems of the lung‘ based on the precepts of oriental medicine. As a result, the function of the lung is to be understood based on the characteristics of the 'Keum Un Qi Hua'. Furthermore we can know that the physiological systems of the lung mirrors the functional changes of the lung.

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A Herbological Study on the Plants of Boraginaceae in Korea (한국산 지치과 식물에 관한 본초학적 연구)

  • Lee, Soong-In;Jeon, Ui-Sang;Jeong, Jong-Gil
    • The Korea Journal of Herbology
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    • v.35 no.6
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    • pp.1-9
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    • 2020
  • Objective : For the purpose of developing Boraginaceae plants recorded in Korean Herbology in Korea, the literatures of the successive generations have been thoroughly investigated to prepare this article. Methods : Books and research papers about Herbology which published at Korea and other countries were examined. Results : A list was made about Boraginaceae plant which were cultivated or grew naturally in Korea, after investigated the data on domestic and foreign Boraginaceae plants. Boraginaceae(grew in Korea) were divided into 14 classes with 24 species. Out of those, 6 classes with 9 species were found serviceable which indicates 37.5% of all. Out of all 24 species of Boraginaceae family, Trigonotis genus were found 5 species, which were shown the most. Among 3 genus of Lithospermum species, medicinal plants were all one species each. Out of all serviceable parts in Boraginaceae, Herb·Radix·Fructus parts took first place as 3 species. There are 2 species toxic, the survey said. 3 Classifying medicinal plants among the Borginaceae plants by part, whole herbs, roots, and fruits are found to be 3 separate species each. When it comes to the nature of taste, 5 kinds of taste without action and seven kinds of bitter taste are the most common. For channel tropism, liver channel has the largest number of 5 types. Conclusion : There were totaled to 14 genera and 24 species in Boraginaceae in Korea and among them medicinal plants are 6 genera, 9 species, some 37.5% in total.

Efficient Usage of Secondary Scramble Code via Optical Repeater in W-CDMA System (W-CDMA 시스템에서 광중계기를 이용한 secondary-스크램블 코드의 효율적 활용방안에 대한 연구)

  • Jeon, Eun-Sung;Park, Jun-Hyo;Yang, Jang-Hoon;Kim, Dong-Ku
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.8C
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    • pp.731-741
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    • 2009
  • Optical repeater is often installed at the isolated area. Spatial separation makes it possible to reduce the inter-code interference when secondary scrambling codes are used for traffic connected through repeater. In this paper, we propose five secondary scrambling code usage scenarios with the aids of optical repeater to maximize the user capacity. In order to evaluate the performance, dynamic system level simulation is performed. We also propose a base station-repeater switching where each active users can change access points by comparing the channel condition from base station and repeater thorough secondary common pilot channel (S-CPICH) signal to noise-interference ratio (SINR). Moreover, primary-secondary scramble code replacing scheme is proposed which replaces secondary scramble code with primary scramble code when a call using primary scramble code is ended and its corresponding OVSF code is available to users using the secondary scramble code

Performance of Hybrid DS/FH Spread-Spectrum Systems in Cellular Packet Radio Network (셀룰러 패킷무선망에서 하이브리드 DS/FH 확산대역 시스팀의 성능)

  • 조현욱;박상규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.10A
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    • pp.1462-1470
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    • 1999
  • In this paper, the performance of packet radio networks using the ALOHA protocol in Rayleigh fading channels is analyzed in terms of the capture probability and the throughput. We consider capture effect in order to increase the probability of the channel access and to include cellular environment we assume that the traffic is a truncated bell-shaped distribution. The packet proposed in this paper consists of a competition part and a data part to decrease the probability of collision in the channel access. In the competition part, DS system with common spreading code is used and in the data, hybrid DS/FH system is used. We consider the linear correlation receiver and the hard-limiting correlation receiver as the receiver model. BPSK modulation is also employed. Because hybrid DS/FH systems are not sensitive to variation of the interference power, as we choose a proper chip number N and a frequency hopping number q, we can obtain a steady system performance even though the variation of interference power is severe fading channels such as Rayleigh fading.

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Performance analysis of multiple access mechanism based on error adaptation in CDMA cellular system (CDMA 셀룰러 시스템용 오율 적응 다중 엑세스 기법의 성능분석)

  • 송상호;조동호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.3
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    • pp.713-720
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    • 1996
  • In recent, the demand of mobile communication system is increasing rapidly. However, since wireless resources is limitted, the protocol to utilize wireless resource efficiently is needed. Up to now, Slotted CDMA_ALOHA(S_CDMA_ALOHA) and Mini-Slotted CDMA_ALOHA(MS_CDMA_ALOHA) methods are proposed as a CDMA_ALOHA mechanism, and it is turned out that MS_CDMA_ALOHA offers betterperformance than S_CDMA_ALOHA mechanism. Also, IS-95 multiple access mechanism has been proposed as common air interface(CAI) protocol of CDMA digital cellular system. However, in former study, the performance evaluations were made without considertion of chnnel characteristics of wireless communication environment. In this paper, a new access mechanism for improring the performance in the DS/CDMA digital cellular environment is suggested. This mechanism is adaptive to the channel condition and based on the conventional MS_CDMA_ALOHA mechanism. Also, the performance of new access mechanism is compared with that of conventional mechanisms, through computer simulation. According tot h simulation results, it is shown that the proposed NA_CDMA_ALOHA(Noise-Adaptation CDMA_ALOHA) mechanism offers better performance than conventional three CDMA_ALOHA mechanisms in view of mean delay time and system throughput characteristics. This phenomenon is due to the fast that NA_CDMA_ALOHA mechanism controls the access attempts efficiently based on the channel condition in heavy traffic environments.

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뉴로모픽 시스템용 시냅스 트랜지스터의 최근 연구 동향

  • Nam, Jae-Hyeon;Jang, Hye-Yeon;Kim, Tae-Hyeon;Jo, Byeong-Jin
    • Ceramist
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    • v.21 no.2
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    • pp.4-18
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    • 2018
  • Lastly, neuromorphic computing chip has been extensively studied as the technology that directly mimics efficient calculation algorithm of human brain, enabling a next-generation intelligent hardware system with high speed and low power consumption. Three-terminal based synaptic transistor has relatively low integration density compared to the two-terminal type memristor, while its power consumption can be realized as being so low and its spike plasticity from synapse can be reliably implemented. Also, the strong electrical interaction between two or more synaptic spikes offers the advantage of more precise control of synaptic weights. In this review paper, the results of synaptic transistor mimicking synaptic behavior of the brain are classified according to the channel material, in order of silicon, organic semiconductor, oxide semiconductor, 1D CNT(carbon nanotube) and 2D van der Waals atomic layer present. At the same time, key technologies related to dielectrics and electrolytes introduced to express hysteresis and plasticity are discussed. In addition, we compared the essential electrical characteristics (EPSC, IPSC, PPF, STM, LTM, and STDP) required to implement synaptic transistors in common and the power consumption required for unit synapse operation. Generally, synaptic devices should be integrated with other peripheral circuits such as neurons. Demonstration of this neuromorphic system level needs the linearity of synapse resistance change, the symmetry between potentiation and depression, and multi-level resistance states. Finally, in order to be used as a practical neuromorphic applications, the long-term stability and reliability of the synapse device have to be essentially secured through the retention and the endurance cycling test related to the long-term memory characteristics.

Monitoring of Pyrethroid Resistance Allele Frequency in the Common Bed Bug (Cimex lectularius) in the Republic of Korea

  • Cho, Susie;Kim, Heung-Chul;Chong, Sung-Tae;Klein, Terry A.;Kwon, Deok Ho;Lee, Si Hyeock;Kim, Ju Hyeon
    • Parasites, Hosts and Diseases
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    • v.58 no.1
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    • pp.99-102
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    • 2020
  • Two-point mutations (V419L and L925I) on the voltage-sensitive sodium channel of bed bugs (Cimex lectularius) are known to confer pyrethroid resistance. To determine the status of pyrethroid resistance in bed bugs in Korea, resistance allele frequencies of bed bug strains collected from several US military installations in Korea and Mokpo, Jeollanamdo, from 2009-2019 were monitored using a quantitative sequencing. Most bed bugs were determined to have both of the point mutations except a few specimens, collected in 2009, 2012 and 2014, having only a single point mutation (L925I). No susceptible allele was observed in any of the bed bugs examined, suggesting that pyrethroid resistance in bed bug populations in Korea has reached a serious level. Large scale monitoring is required to increase our knowledge on the distribution and prevalence of pyrethroid resistance in bed bug populations in Korea. Based on present study, it is urgent to restrict the use of pyrethroids and to introduce effective alternative insecticides. A nation-wide monitoring program to determine the pyrethroid resistance level in bed bugs and to select alternative insecticides should be implemented.

Presenilin Modulates Calcium-permeant, Magnesium-Nucleotide regulated channel, I(MgNUM)

  • Shin, Sun-Young;Jeong, Soon-Youn;Uhm, Dae-Yong;Sungkwon Chung
    • Proceedings of the Korean Biophysical Society Conference
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    • 2003.06a
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    • pp.47-47
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    • 2003
  • The presenilin 1 (PS1) or PS2 is an essential component of the ${\gamma}$-secretase complex, which mediates the intramembrane proteolysis of selected type-I membrane, including the ${\beta}$-amyloid precursor protein (APP) to yield A${\beta}$. Familial Alzheimer's disease (FAD)-associated mutations in presenilins give rise to an increased production of a highly amyloidogenic A${\beta}$42. In addition to their well-documented proteolytic function, the presenilins play a role in calcium signaling. We have previously reported that presenilin FAD mutations cause highly consistent alterations in intracellular calcium signaling pathways, which include deficits in capacitative calcium entry (CCE), the refilling mechanism for depleted internal calcium stores. However, molecular basis for the presenilin-mediated modulation of CCE remains to be elucidated. In the present study, whole-cell patch clamp method was used to identify a specific calcium-permeable ion channel current(s) that is responsible for the CCE deficits associated with FAD-linked PS1 mutants. Unexpectedly, both voltage-activated and conventional store depletion-activated calcium currents I(CRAC), were absent in HEK293 cells, which were stably transfected either with wild-type or FAD mutant (L286V, M146L, and delta E9) forms of PS1. Recently, magnesium-nucleotide-regulated metal cation current, or I(MagNum), has been described and appears to share many common properties with I(CRAC) including calcium permeability and inhibitor sensitivity (e.g. 2-APB). We have detected I(MagNum) in all 293 cells tested. Interestingly, FAD mutant 293 cells developed only about half of currents compared to PS1 wild type cells.

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Design of intelligent Traffic Control System using Multiprocessor Architecture (멀티 프로세서 구조를 이용한 지능형 교통신호 제어시스템 설계)

  • 한경호;정길도
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.12 no.2
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    • pp.62-68
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    • 1998
  • In this paper, we proposed the design of the intelligent traffic control system by using multiprocessor architecture. The inter-processor communication of the architecture is implemented by sharing the serial communication channel. In comparing the conventional traffic control system using single processor architecture, the proposed system uses multiple processors controlling the sub systems such as the signal lights, traffic measurement unit, auxiliary signal lights and peripherals. The main processor controls the communication among the processors and the communication protocol link to the central control center at remote site. The proposed architecture reduces the load and simplifies the program of each processor and enables the real time processing of the add-on features of intelligent traffic control systems. The architecture is implemented and the common channel inter-processor communications and the real time operation is experimented .experimented .

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