• Title/Summary/Keyword: MISO

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Margin Adaptive Optimization in Multi-User MISO-OFDM Systems under Rate Constraint

  • Wei, Chuanming;Qiu, Ling;Zhu, Jinkang
    • Journal of Communications and Networks
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    • v.9 no.2
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    • pp.112-117
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    • 2007
  • In this paper, we focus on the total transmission power minimization problem for downlink beamforming multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems while ensuring each user's QoS requirement. Although the linear integer programming (LIP) solution we formulate provides the performance upper bound of the margin adaptive (MA) optimization problem, it is hard to be implemented in practice due to its high computational complexity. By regarding each user's equivalent channel gain as approximate independent values and using iterative descent method, we present a heuristic MA resource allocation algorithm. Simulation results show that the proposed algorithm efficiently converges to the local optimum, which is very close to the performance of the optimal LIP solution. Compared with existing space division multiple access (SDMA) OFDM systems with or without adaptive resource allocation, the proposed algorithm achieves significant performance improvement by exploiting the frequency diversity and multi-user diversity in downlink multiple-input single-output (MISO) OFDM systems.

Outage Probability Analysis of Multiuser MISO Systems Exploiting Joint Spatial Diversity and Multiuser Diversity with Outdated Feedback

  • Diao, Chunjuan;Xu, Wei;Chen, Ming;Wu, Bingyang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.9
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    • pp.1573-1595
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    • 2011
  • In this paper, the outage performance of multiuser multiple-input single-output (MISO) systems exploiting joint spatial and multiuser diversities is investigated for Rayleigh fading channels with outdated feedback. First, we derive closed-form exact outage probabilities for the joint diversity schemes that combine user scheduling with different spatial diversity techniques, including: 1) transmit maximum-ratio combining (TMRC); 2) transmit antenna selection (TAS); and 3) orthogonal space-time block coding (OSTBC). Then the asymptotic outage probabilities are analyzed to gain more insights into the effect of feedback delay. It is observed that with outdated feedback, the asymptotic diversity order of the multiuser OSTBC (M-OSTBC) scheme is equal to the number of transmit antennas at the base station, while that of the multiuser TMRC (M-TMRC) and the multiuser TAS (M-TAS) schemes reduce to one. Further by comparing the asymptotic outage probabilities, it is found that the M-TMRC scheme outperforms the M-TAS scheme, and the M-OSTBC scheme can perform best in the outage regime of practical interest when the feedback delay is large. Theoretical analysis is verified by simulation results.

The Effect of Miso Facial Acupuncture on Facial Reduction and Improvement of Skin Condition (미소안면침의 얼굴 축소 및 피부상태 개선 효과)

  • Kwon, Gi-Sun;Kim, Jung-Hee;Lee, Kyeong-A;Lee, Soo-Jung;Song, Jeong-Hwa;Song, Choon-Ho;Youn, Hyoun-Min;Jang, Kyung-Jeon;Kim, Cheol-Hong
    • Journal of Acupuncture Research
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    • v.29 no.4
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    • pp.7-18
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    • 2012
  • Objectives : The purpose of this study is to evaluate the effects of Miso facial acupuncture on facial reduction and improvement of skin condition. Methods : From March to May 2012, 20 women in their twenties to forties with no facial diseases were recruited. Miso facial acupuncture was performed on the both side of their face twice a week, total seven times. The 3D face photographs of each participant were checked 5 times ; before treatment, after 1st treatment, 4th treatment, 7th treatment and 10 days from the last treatment using RS-400FL(Morpheus Co. Korea) and REAL FACE. The surface distances of the 4 lines on the face were measured using Renai MEF program. The improvement of skin condition was evaluated by water content, trans epidermal water loss(TEWL), erythema index and melanin index using MPA 5. They were checked 4 times ; before treatment, 4th treatment, 7th treatment and after 10 days from the last treatment. We analyzed data using Paired t-test(p<0.05) and Wilcoxon signed rank test(p<0.05). Results : One case was dropped out due to pain and edema after 4th treatment. The surface distances of the 4 lines on face were significantly reduced and maintained after 10 days from last treatment. Water content was significantly increased and maintained after 10 days from last treatment. TEWL was significantly decreased. Erythema index was significantly decreased from the 3rd evaluations. Melanin index was slight decreased with no significance at the 2nd evaluations. Conclusions : These results show that Miso facial acupuncture can reduce sizes of the face and improve skin condition such as water content, TEWL and erythema index except melanin index.

시판 된장 첨가에 따른 밀가루 반죽과 gluten 물성에 미치는 효과

  • 김창순;오현주;이지혜
    • Proceedings of the Korean Society of Food and Cookery Science Conference
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    • 2003.05a
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    • pp.81-81
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    • 2003
  • 일반적으로 빵 반죽의 물성이 최종 제품의 품질에 영향을 크게 미치는 것으로 알려져 있다. 발효 식품인 된장은 유리당, 유리아미노산, 유리지방산, 유기산, 환원당, 단백질 가수분해물 등 발효생성물을 함유하고 있다. 본 연구에서는 제빵 시 시판 된장의 첨가가 밀가루 반죽과 gluten 물성에 미치는 효과를 조사하기 위해 재래식 된장(A) 1종과 국내에서 시판되고 있는 개량식 된장(B, C, D, E) 4종 Miso type 된장(F) 1종, Miso(G) 1종을 동결건조 후 분발 상태로 2.5∼10.0%를 반죽에 첨가하였으며, 이때 밀가루 반죽의 최종 염도는 모든 반죽이 동일하도록 소금의 첨가량을 각각 조절하였다. (중략)

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A Study of Mastless Pattern Fabrication using Stereolithography (광조형을 이용한 마스크리스 패턴형성에 관한 연구)

  • 정영대;조인호;손재혁;임용관;정해도
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.503-507
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    • 2002
  • Mask manufacturing is a high COC and COO process in developing of semiconductor devices, because of the mass production tool with high resolution. Direct writing has been thought to be one of the patterning method to cope with development or small-lot production of the device. This study focused on the development of the direct, mastless patterning process using stereolithography tool for the easy and convenient application to micro and miso scale products. Experiments are utilized by three dimensional CAD/CAM as a mask and photo-curable resin as a photo-resist in a conventional stereo-lithography apparatus. Results show that the resolution of the pattern was achieved about 300 micron because of complexity of SLA apparatus settings, inspite of 100 micro of inherent resolution. This paper concludes that photo resist and laser spot diameter should be adjusted to get finer patterns and the proposed method is significantly feasible to mastless and low cost patterning with micro and miso scale.

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Interactive Cooperative Communication Scheme for OFDMA System (OFDMA 시스템에서 양방향 협력통신기법)

  • Kim, Ki-Ro;You, Young-Hwan;Song, Hyoung Kyu
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2013.06a
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    • pp.219-220
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    • 2013
  • 무선통신에서 다중안테나를 사용하지 않고 다이버시티 이득을 얻기 위한 대안으로 협력 통신 기법이 개발되어 왔다. 하지만 대부분의 협력기법들은 릴레이에 신호를 전송하는 과정에서 delay 가 발생하게 되어 전송률이 감소하는 단점이 있다. 본 논문에서는 OFDMA 시스템에서 feedback 정보를 이용하는 기법을 사용하여 전송 손실이 발생하지 않으면서 기존의 MISO(multi input multi output)시스템과 비슷한 성능을 갖는 새로운 협력모델을 제안한다. 제안된 기법은 bit error rate(BER) 관점에서 평가되고 협력하는 사용자와의 채널이 보장되면 기존의 MISO 기법과 비슷한 성능을 보이는 것을 보여준다.

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Antimutagenic Effect of Doenjang(Korean Fermented Soy Paste) toward Aflatoxin (된장의 Aflatoxin $B_1$에 대한 항돌연변이 효과)

  • 박건영;문숙희;백형석;최홍식
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.19 no.2
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    • pp.156-162
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    • 1990
  • Antimutagenic effect of doenjag (Korean fermented soy paste) on mutagenesis induced by aflatoxin B1 (AFB1) in Salmonella typhimurium strains TA98 and TA100 was studied. AFB1 revealed maximum mutagenicity at dose level of 1 $\mu$g/plate with metabolic activation system in both strains. Strong antiutagenic activity toward AFB1 was completely inhibited at the level of 50% of the doenjang extract. At the same concentration 64-66% and 39-53% of the AFB1 induced mutageneses were blocked when the methanol extracts of raw and cooked soybeans were added in the system respectively Raw soybeans showed higher ihhibition rate to the mutagenicity than cooked soybeans but the fermented soybeans(doenjang) was the most effective (p<0.05) Other soybean fermented foods such as commercial doenjang natto and miso were also exhibited some antimutagenic activities however the traditional doenjang was the most effective and then commercial doenjang. Natto and miso were less effective.

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Performance of Receive Diversity UWB Systems with Pulse Amplitude and Position Modulation

  • Kim, Sang-Choon
    • Journal of information and communication convergence engineering
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    • v.8 no.5
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    • pp.498-501
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    • 2010
  • In this paper, we extend ultra-wideband (UWB) single input single output (SISO) systems with a hybrid pulse amplitude and position modulation (PAPM) to single input multiple output (SIMO) systems using receive antenna diversity. The performance of a rake receive diversity combining scheme for UWB SIMO systems with a PAPM is examined in a log-normal multipath fading channel and also compared with that of a time-switched transmit diversity (TSTD) multiple input single output (MISO) system. It is seen that as the number of receive antennas increases, the receive diversity combining system improves the error performance. It is shown that the TSTD UWB MISO systems offer the performance equivalent to the receive diversity combining scheme for SIMO systems.