• 한국통신학회논문지
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• 제16권2호
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• pp.137-144
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• 1991

A new demodulation scheeme for differentially encoded GMSK signal is introduced and described. In the proposed differential detection method, the signal is sampled at the center of the time slot, at which the effect of the intersymbol interference is relatively smaller than the edge of the time slot. The proposed differential detector takes this adbantate. The error rate performance of the differential detector has been numerically calculated in the fast fading encountered in the land mobile radio channels. A comparison of performance with the differential detector for MSK signal is given. Finally the possibility of improving performance employing nonredudant error correction is studied.

• Advances in Traditional Medicine
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• 제8권3호
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• pp.215-221
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• 2008

In this present study Indian traditional Ayurvedic herbal formulation Amritaristo has been studied to assess the general pharmacological effect on mice. The drug showed no significant activity on the neuropharmacological test models experimented. The increased pentobarbital sleeping time was considered related with hepatic metabolism of pentobarbital. The formulation exhibited a non-significant reduction of gastrointestinal motility, and devoid of any acute diuretic activity. The tested drug revealed antidiarrhoeal activity on castor oil-induced model, whereas on magnesium sulphate-induced model no effect was observed.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1987년도 춘계학술발표회 논문집
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• pp.223-229
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• 1987

The error rate eqations of digital modulated signals transmitted through the fading cdannel have been derived in the Gaussian/Impulsive noise environments Whing the derived equations for the error drobadillties of ASK, QAM, FSK, MSK, PSK, and DPSK signais, the error tate performance of digital modulation systems have been evaluated and represented in the graghes as parameters of carrier to \ulcornernoise power ratio (CNR) and fading figures The results show that in the fading environenet the error is occurred more frequently by gaussian noise in the deep fading Howerer in the shallow fading lmpulsive noise is more domiant than gaussian nosie in occurring the error

• 한국통신학회논문지
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• 제16권11호
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• pp.1095-1102
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• 1991

본 논문에서는 2-h CPM의 차동 복조 방식을 제안하고 이에 따른 오율 성능을 분석한다. 차동 복조에 적합한 변조지수 집합을 도출하고 이로부터 얻어진 변조지수에 따른 전력 스펙트럼을 구하여 기존의 MSK와 OPSK등과 비교,분석하였다. 또한 제안된 차동 검파기에 의한 오율 성능과 2-h CPM의 차동 복조식 비터비검파기를 적용시켜 얻은 오율 성능 등을 비교, 분석하였다.

• Advances in Traditional Medicine
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• 제5권1호
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• pp.37-42
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• 2005

The crude methanolic extract of the leaves of Amoora cucullata Roxb. was investigated for its possible anti-inflammatory activity using carrageenin induced rat paw edema model and cotton pellet implantation method in rat. The extract was also studied for its antinociceptive activity using acetic acid induced writhing model in mice. At the doses of 200 and 400 mg/kg body weight, the extract showed significant anti-inflammatory activity in both models. At the same doses, the extract also significantly reduced the number of acetic acid-induced abdominal constriction (writhing) in mice. The crude extract also showed significant diuretic activity in albino mice.

• Advances in Traditional Medicine
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• 제6권3호
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• pp.215-220
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• 2006

The Sundarbans mangrove forest has a rich biodiversity of flowering plants and many of these have been used in traditional medicine although the flora remains comparatively uninvestigated scientifically. Xylocarpus granatum, Xylocarpus moluccensis and Excoecaria agallocha methanolic extract showed a central nervous system depressant activity on the hole cross and open field test at 800 mg/kg dose level. The most significant depressant activity was observed in Xylocarpus granatum followed by Xylocarpus moluccensis and Excoecaria agallocha. There was no depressant activity observed in the models for Sarcolobus globosus. Further studies are required to confirm the activity and to explain the mechanism.

• Advances in Traditional Medicine
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• 제3권2호
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• pp.63-71
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• 2003

The psycho-pharmacological effect of BRHAT VATACHINTAMANI RASA (BVC) an Ayurvedic preparation was investigated, both in animal and clinical models. It was observed that BVC possess a sedative or quitening effect in that it significantly decreased the spontaneous motor activity, and also lowered the exploratory behavior of the amphetamine treated animals. This was further evident by increase in climbing out time and taming effect on animal in isolation induced aggression test. Apart from very high dose it seems have little effect on pentobarbital sleeping time and narcotic analgesic test. The drug BVC increases performance of the animal in forced locomotor test. The effect of VATACHINTAMANI RASA on clinical study was not significant.

• Journal of information and communication convergence engineering
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• 제7권3호
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• pp.304-308
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• 2009

This paper proposes a new concept of a signal constellation of the recently introduced half-symbol-rate-carrier phase-shift keying (HSRC-PSK) modulations for bandwidth-efficient high speed data communications. Since the HSRC-PSK modulations contain different symbol energies representing the same bit sequences due to the loss of orthogonality of their HSRC signals, it is very hard to represent the symbol using the conventional signal constellation. To resolve the problem, two different energies are assigned to represent one symbol for the HSRC offset quadrature phase shift keying (OQPSK) modulation. Similarly, the different energies exist to display the different symbol for HSRC minimum shift keying (MSK) modulation. With the proposed signal space representation, HSRC-PSK symbol can easily be shown with a two-dimensional scatter plot which provides helpful information of evaluating HSRC-PSK signal's quality.

• Journal of Plant Biology
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• 제37권3호
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• pp.381-385
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• 1994

The highest degree of callus formation was obtained from the shoot tips of Dianthus superbus when cultured on the MS medium supplemented with 2.0 mg/L NAA and 0.5 mg/L BAP. Embryogenic calluses were obtained from the seperated friable calluses on MS medium containing 2.0 mg/L 2,4-D after 7-8 wk of culture. For plant regeneration, embryogenic calluses were selected and cultured on te proliferation medium. After 3 wk, somatic embryos appeared on MSK medium (0.5 mg/L NAA, 2.0 mg/L kinetin) and N6 medium (2.0 mg/L kinetin, 0.1 mg/LNAA, 0.1 mg/L 2,4-D and 2.0 g/L casein hydrolysate). When these somatic embryos were kept under continuous illumination, shoots were successfully regenerated on the both media. The shoots were rooted on MS medium supplemented with 2.0 mg/L NAA.

• 한국음향학회지
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• 제17권4호
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• pp.28-34
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• 1998

미래 개인 휴대통신에서는 고속의 데이터 서비스를 위하여 높은 대역폭 효율을 요 구하게 된다. 무선통신 서비스를 향상시키기 위하여 코딩기법, 변조기법, 다중화기법 등의 다양한 방법이 연구되고 있다. 이중에서 특히 변조기법은 시스템의 성능을 결정하는 중요한 요소가 된다. 본 논문에서는 PSK. OQPSK, π/4 DQPSK, MSK, GMSK의 다섯가지 변조기 법에대한 BER성능을 시뮬레이션하였다. 시뮬레이션을 위한 다중경로 페이딩채널로서 3가지 서로 다른 채널을 적용하였다. 이때 시뮬레이션을 위하여 1.544Mbps의 전송속도와 1.9GHz 의 반성주파수 환경을 고려하였다. 또한 fractional 선형 등화기를 적용하여 변조방식에 따른 성능향상 정도를 비교하였다. 채널 Ⅰ, Ⅱ, Ⅲ에 대해 각각 30dB, 20dB, 10dB 정도에서 error floor현상이 발생했으며 π/4 DQPSKS가 가장 낮은 BER 특성을 보인 반면 QPSK는 가장 높은 BER을 나타냈다. 등화기를 적용했을 때는 GMSK의 성능향상이 가장 크게 나타 났다.