• Journal of Communications and Networks
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• v.13 no.5
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• pp.481-493
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• 2011

Multiple-input multiple-output (MIMO) technology provides high data rate and enhanced quality of service for wireless communications. Since the benefits from MIMO result in a heavy computational load in detectors, the design of low-complexity suboptimum receivers is currently an active area of research. Lattice-reduction-aided detection (LRAD) has been shown to be an effective low-complexity method with near-maximum-likelihood performance. In this paper, we advocate the use of systolic array architectures for MIMO receivers, and in particular we exhibit one of them based on LRAD. The "Lenstra-Lenstra-Lov$\acute{a}$sz (LLL) lattice reduction algorithm" and the ensuing linear detections or successive spatial-interference cancellations can be located in the same array, which is considerably hardware-efficient. Since the conventional form of the LLL algorithm is not immediately suitable for parallel processing, two modified LLL algorithms are considered here for the systolic array. LLL algorithm with full-size reduction-LLL is one of the versions more suitable for parallel processing. Another variant is the all-swap lattice-reduction (ASLR) algorithm for complex-valued lattices, which processes all lattice basis vectors simultaneously within one iteration. Our novel systolic array can operate both algorithms with different external logic controls. In order to simplify the systolic array design, we replace the Lov$\acute{a}$sz condition in the definition of LLL-reduced lattice with the looser Siegel condition. Simulation results show that for LR-aided linear detections, the bit-error-rate performance is still maintained with this relaxation. Comparisons between the two algorithms in terms of bit-error-rate performance, and average field-programmable gate array processing time in the systolic array are made, which shows that ASLR is a better choice for a systolic architecture, especially for systems with a large number of antennas.

• Journal of Oral Medicine and Pain
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• v.35 no.1
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• pp.31-39
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• 2010

This study is to observe the bacteriocidal effect of the Low Level Laser (LLL) against oral microorganisms which are related to the occurrence of periodontal diseases and oral malodors. The Porphyromonas gingivalis 2561 (P. gingivalis 2561) and Prevotella intermedia (Pr. intermedia) were treated with photosensitizing substance-toluidine blue O (TBO; C.I. 52040) and then radiated with the LLL which has 650nm wavelength for 1, 2, 3 and 5mins. continuously upon varying distances of 1, 2 and 3cm for each experimental groups. The results are as follows; 1. The P. gingivalis 2561 which was treated with TBO and then radiated with LLL at a distance of 3cm for 1min. showed 99.99% higher antibacterial effect in comparison to the experimental group treated only with TBO. 2. The Pr. intermedia which was treated with TBO and then radiated with LLL at a distance of 3cm for 1min. showed 99.8% higher antibacterial effect in comparison to the experimental group treated only with TBO. 3. The bacteriocidal effect of the P. gingivalis 2561 treated with TBO was found to gradually increase as the radiation time of LLL extended from 1min. to 3min. at 1min. intervals. 4. A slight decrease in bacteriocidal effect of the P. gingivalis 2561 was found as the radiation distance of LLL increased from 1cm to 3cm at 1cm intervals. 5. The bacteriocidal effect of the Pr. intermedia was found to slightly decrease as the radiation distance of LLL increased from 1cm to 3cm at 1cm. intervals. As the results shown above suggest, the bacteriocidal effect of LLL was found to increase as the radiation time extended and the distance shortened. Moreover, even the experimental group radiated with LLL at 3cm distance for 1min. which showed the lowest level of bacteriocidal effect, was found to have 99.8% higher bacteriocidal effect than the experimental group which was treated only with TBO and, therefore, this clearly shows the bacteriocidal effect of LLL against oral microorganisms. Thus, the use of LLL is thought to become very useful for suportive treatment for periodontitis and implantitis, and controlling oral malodors as long as it is used within the limits where there is no side effect.

• Journal of Chest Surgery
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• v.47 no.2
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• pp.193-196
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• 2014

We report a rare case of granular cell tumor arising in the left lower lobe (LLL) bronchus with secondary obstructive change in a 60-year-old male. The patient was found to have a nodule in the LLL on a computed tomography scan, three months prior to his presentation to the Asan Medical Center. Bronchoscopic biopsies revealed a granular cell tumor. After undergoing LLL lobectomy with bronchoplasty, the patient has not experienced any tumor recurrence.

• Journal of the korean veterinary medical association
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• v.18 no.4
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• pp.66-72
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• 1982

• Journal of the korean veterinary medical association
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• v.18 no.8
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• pp.61-66
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• 1982

• Journal of the korean veterinary medical association
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• v.18 no.2
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• pp.61-66
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• 1982

• Journal of the korean veterinary medical association
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• v.18 no.3
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• pp.51-57
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• 1982

• Journal of the korean veterinary medical association
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• v.18 no.5
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• pp.60-67
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• 1982

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.102-108
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• 1991

Raw adlay powder(RAP)was prepared and the changes of triglyceride composition in RAP lipid during storage at $35^{\circ}C$ for six months were studied. The RAP lipid consisted of 28 kinds of triglycerides and the major triglyceride in RAP lipid were those of OOL(24.14%), OLL(24.06%), OOO(12.58%), POL(9.01%), POO(8.87%), LLL(7.91%)and PLL(5.80%). During the storage at $35^{\circ}C$ for six months, the relative amounts of the triglyceride containing linoleic acid(OLL : 15.25%, LLL : 2.93%)considerably decreased, but those containing oleic acid(OOO : 23.77%. POO : 12.62%) increased. The triglycerides of LLA(0.44%)and PPLn(0.12%)disappeared during the storage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11A
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• pp.852-861
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• 2009

We propose a complexity reduced Lattice Reduction(LR) scheme for MIMO detection under time varying fading environments. It is found that for successive MIMO transmission instances, the integer matrix P after LR decomposition remains the same or only a few elements of the matrix P are slightly changed. Based on this feature, we perform LR reduction by setting the initial values for P matrix for the decomposition to be the one obtained in the previous instance not starting from the identity matrix. Simulation results reveal that the proposed scheme drastically reduces overall complexity of LR reduction compared to the conventional scheme for various system parameters under time varying channels. We also show that the proposed scheme can be applied to Seysen LR as well as LLL(Lenstra, Lenstra, and Lavasaz)-LR.