• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4B
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• pp.584-591
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• 2010

In this paper, we propose an adaptive Relay Station (RS) coverage extension scheme for the Mobile Multi-hop Relay (MMR) systems. The MMR system with a non-transparent mode RS can be used to extend BS coverage using the remaining capacity of the Base Station(BS). Thus, the call blocking may occur in RSs when calls arrive very often in Multi-hop Relay Base Station (MR-BS). In the proposed scheme, RSs can be connected to the neighbor MMR system as the 2ndtier RSs if the neighbor MMR system services low traffic load when calls are frequently arrived in MR-BS or RSs. By doing so, the MMR system can accept a new call without call blocking. Through numerical results, we demonstrate that the proposed scheme outperforms the conventional MMR system in terms of the throughput and call blocking probability of MMR systems.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.2
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• pp.223-234
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• 2008

Mobile multi-hop relaying (MMR) technology is being considered as a promising solution capable to enhance coverage, user throughput, and system capacity of the current wired backbone dependent wireless access networks. Since the relaying nodes do not need a wired backbone access, MMR technology offers easy and low-cost deployment, flexible cell planning, and adaptive traffic handling performance. In this paper, we investigate performance and cost effectiveness of the MMR technology deployment in the IEEE802.16j based WiBro/WiMAX systems. We first introduce standardization activities and research issues of MMR WiBro/ WiMAX systems. Since the coverage extension problem may occur in metropolitan areas as well as suburban or rural areas where user density is relatively low or moderate, we introduce several MMR topologies and analyze cost-effectiveness of MMR based coverage extension with respect to the user traffic density. Then, we argue cost effect on MMR technology deployment and throughput performance, Finally, we introduce further study issues including sectorized base station based MMR deployment approaches and the single and multi-frame structure MMR approaches.

• Journal of the Korean Society for Library and Information Science
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• v.52 no.4
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• pp.91-110
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• 2018

We proposed a video summarization algorithm based on an ERP (Event Related Potentials)-based topic relevance model, a MMR (Maximal Marginal Relevance), and discriminant analysis to generate a semantically meaningful video skim. We then conducted implicit and explicit evaluations to evaluate our proposed ERP/MMR-based method. The results showed that in the implicit and explicit evaluations, the average scores of the ERP / MMR methods were statistically higher than the average score of the SBD (Shot Boundary Detection) method used as a competitive baseline, respectively. However, there was no statistically significant difference between the average score of ERP/MMR (${\lambda}=0.6$) method and that of ERP/MMR (${\lambda}=1.0$) method in both assessments.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.2
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• pp.43-50
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• 2004

The Statistic-based method is widely used for automatic single document summarization in large sets of documents such as those on the web. However, the results of this method shows high redundancies in the summarized sentences because this method selects sentences including words that frequently appear in the document. We solve this problem using the method MMR to raise the quality of document summary (The best results are appeared around λ=0.6). Also, we compare the MMR summaries with those done by human subjects and verify their accuracy.

• Journal of Gastric Cancer
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• v.23 no.2
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• pp.264-274
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• 2023

Purpose: In this study, polymerase chain reaction (PCR)-based microsatellite instability (MSI) testing was comprehensively analyzed and compared with immunohistochemistry (IHC) for mismatch repair (MMR) protein expression in patients with gastric cancer (GC). Materials and Methods: In 5,676 GC cases, PCR-based MSI testing using five microsatellites (BAT-26, BAT-25, D5S346, D2S123, and D17S250) and IHC for MLH1 were performed. Reevaluation of MSI testing/MLH1 IHC and additional IHC for MSH2, MSH6, and PMS2 were performed in discordant/indeterminate cases. Results: Of the 5,676 cases, microsatellite stable (MSS)/MSI-low and intact MLH1 were observed in 5,082 cases (89.5%), whereas MSI-high (MSI-H) and loss of MLH1 expression were observed in 502 cases (8.8%). We re-evaluated the remaining 92 cases (1.6%) with a discordant/indeterminate status. Re-evaluation showed 1) 37 concordant cases (0.7%) (18 and 19 cases of MSI-H/MMR-deficient (dMMR) and MSS/MMR-proficient (pMMR), respectively), 2) 6 discordant cases (0.1%) (3 cases each of MSI-H/pMMR and MSS/dMMR), 3) 14 MSI indeterminate cases (0.2%) (1 case of dMMR and 13 cases of pMMR), and 4) 35 IHC indeterminate cases (0.6%) (22 and 13 cases of MSI-H and MSS, respectively). Finally, MSI-H or dMMR was observed in 549 cases (9.7%), of which 47 (0.8%) were additionally confirmed as MSI-H or dMMR by reevaluation. Sensitivity was 99.3% for MSI testing and 95.4% for MMR IHC. Conclusions: Considering the low incidence of MSI-H or dMMR, discordant/indeterminate results were occasionally identified in GCs, in which case complementary testing is required. These findings could help improve the accuracy of MSI/MMR testing in daily practice.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.8A
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• pp.813-819
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• 2007

In this paper, the effect of a propagation delay resulting from the use of an OFDM-based cellular system with a transparent mobile multi-hop relay(MMR) is initially analyzed. Then, channel estimation techniques, a least square(LS) method and a minimum mean square error(MMSE) method, for the OFDM systems with throughput enhancement(TE) MMR or cooperative MMR are proposed. The proposed channel estimation techniques can overcome the performance degradation caused by the propagation delay in TE MMR or cooperative MMR systems. It is demonstrated by computer simulation that the proposed channel estimation techniques for OFDM systems with transparent MMR are superior to the conventional techniques in terms of mean square error(MSE) and bit error rate(BER).

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11a
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• pp.615-618
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• 2002

정보검색 엔진들은 주어진 질의에 대해 방대한 양의 문서들을 검색해주며, 이 문서들은 질의와의 관련성에 따라 랭킹(Ranting)된다. 질색된 문서들중에 어떤것들은 그 내용이 서로 유사하여 사용자에게 필요 이상의 정보를 제공한다. 이는 질의와의 관련성(Relevance)만을 적용하고, 검색된 정보들간의 차별성을 고려하지 않은데서 비롯된다. MMR(Maximal Marginal Relevance)은 유사한 문서를 검색결과에서 배제할 수 있게 해주는 기법이다. MMR을 자동에 적용하면, 유사한 문장을 배제하여 상이한 정보들을 전달하는 질 높은 요약문을 생성할 수 있다. 본 논문에서는 MMR을 이용한 질의기반 자동 문서요약 시스템을 구현한다. 또한, MMR과 가중치 수식에 다양한 수치를 적용하고, 최적의 결과를 산출하는 수식을 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.3A
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• pp.244-257
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• 2009

We analysed the opportunistic scheduling method in MMR proposed by Samsung Electronic Cooperation and confirmed the efficiency by simulation. We also investigated the relationship between the throughput and fairness under the proposed method. The main objective of this study is to propose an opportunistic packet scheduling method in MMR, which considers the QoS requirement of user. Using the simulation the performance of the proposed method is compared with those of i) pure opportunistic packet scheduling method which doesn't consider QoS requirement and ii) packet scheduling method which only consider the QoS requirement, but does not utilize opportunistic packet scheduling.

• Pediatric Infection and Vaccine
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• v.7 no.2
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• pp.183-192
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• 2000

Purpose : Adverse events(AE) associated with vaccination have not been systematically monitored in Korea. But since 1994, several deaths after inactivated mouse brain derived Japanese encephalitis vaccine injection arouse the safety problem of immunization in the public, and a evaluation of vaccination program including the effectiveness and safety problem had been started. We have been using MMR vaccine containing Japanese mumps vaccine strains, which are known to be associated with the high rate of adverse events including aseptic meningitis, for the last decade. Methods : We conducted a prospective study of vaccine adverse events associated with MMR vaccine through a tracking system using telephone calls. We followed up 7,594 cases of MMR vaccinees. Results : Reported adverse events included fever, couvulsion, parotitis, and aseptic meningitis. Nine cases of parotitis and seven cases of aseptic meningitis were recognized during follow up period. The incidence of both parotitis and aeptic meningitis was $85.1/10^5$, for Urabe mumps strain. For Hoshino strain, the incidence of parotitis and aseptic meningitis was $158.0/10^5$ and $94.8/10^5$, respectively. Conclusions : The incidence of adverse events was to be a higher than that of natural infection in Korea and was comparable to the results of studies done in other countries.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.394-400
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• 2010

Mobile Multi-hop Relaying (MMR) system can provide increased system capacity of wireless access network by coverage extension and enhanced transmission rate within the Base Station (BS) coverage area. The previous researches for the MMR system with a non-transparent mode Relay Station (RS) do not consider channel selection procedure of Mobile Station (MS), co-channel interference and Multi-hop Relay Base Station (MR-BS) coverage and RS coverage ratio in MMR system. In this paper, we investigate the performance of MMR uplink system in multicell environments with various topologies. The performance is presented in terms of call blocking probability, channel utilization, outage probability and system throughput by varying offered load. It is found that, for certain system parameters, the MMR uplink system achieve the maximum system throughput when MR-BS coverage to RS coverage ratio is 7.