• Title/Summary/Keyword: STC

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A Study on the Performance of STC-MIMO System (WiBro STC-MIMO 시스템의 성능 연구)

  • Ahn, Sung-Soo;Cho, Jun-Hwan
    • Journal of Satellite, Information and Communications
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    • v.5 no.1
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    • pp.90-93
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    • 2010
  • This paper shows various perfermance analysis utilizing STC(Space Time Coding) in MIMO mobile communication by WiBro system environments. In this paper, 3 algorithm which are SM method, ML (Maximum Likelihood) and ZF(Zero Forcing) algorithm use for perfermance analysis. From the various simulation result, it is confirm that ZF method is superior compare than STC and ML method.

Study on High Speed Routers(II)-Performance Analysis on Various Network Topology of STC104 (고속 라우터에 대한 고찰(II)-STC104의 망 구성에 따른 성능분석)

  • Lee, Hyo-Jong
    • The KIPS Transactions:PartA
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    • v.8A no.2
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    • pp.157-166
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    • 2001
  • A simulation package has been developed as an event-driven system that can handle the hardware configuration of STC104 and algorithm proposed in the sister paper of ‘Study on High Speed Routers(II).’After various STC104 topology of meshes, torus, and hypercubes are constructed using up to 512 switches, the performance of each topology has been analyzed under different message generation rate in terms of throughputs, latency, and packet blocking time. Modified multicast algorithms for STC104 have been proposed for STC104 after U-mesh and U-torus in order to overcome the multicasting difficulty because of the point-to-point communication method found in STC104. The performance of the multicast algorithms have been analyzed over meshes and torus configuration. Throughput gets higher in the order of mesh, torus, and hypercube. Throughput difference among topology were distinctive in the zone of high message generation rate. Latency and blocking time increased in the order of hypercube, torus, and mesh. U-mesh and U-torus of software multicast showed similar throughput, however, U-mesh peformed slightly better result. These algorithms showed eight to ten times better results compared to individual message pass for 90 destination nodes. Multi-link environment also showed better performance than single-link environment because multi-link network used the extra links for communication.

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A Logit Type of Public Transit Trip Assignment Model Considering Stepwise Transfer Coefficients (Stepwise 환승계수를 고려한 Logit 유형 대중교통통행배정모형)

  • SHIN, Seongil;BAIK, Namcheol
    • Journal of Korean Society of Transportation
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    • v.34 no.6
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    • pp.570-579
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    • 2016
  • This study proposes a concept of Stepwise Transfer Coefficient(STC) which implies greater transfer cost with increasing the number of transfers. Thus, the public transport information system provides the choice sets of travel routes by the consideration of not only transportation time but also the optimum number of transfers. However, path choice problems that involve STC are found to include non additive cost, which requires additional route enumeration works. Discussions on route enumeration in actual transportation networks is very complicated, thereby warranting a theoretical examination of route search considering STC. From these points of view, this study results in a probability based transit trip assignment model including STC. This research also uses incoming link based entire route deletion method. The entire route deletion method proposed herein simplifies construction of an aggregation of possible routes by theoretically supporting the process of enumeration of the different routes from origin to destination. Conclusively, the STC reflected route based logit model is proposed as a public transportation transit trip assignment model.

A Study on the Effect of Containment Filtered Venting System to Off-site under Severe Accident (중대사고시 격납건물여과배기계통(CFVS)적용으로 인한 사고영향과 결과 고찰)

  • Jeon, Ju Young;Kwon, Tae-Eun;Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.40 no.4
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    • pp.244-251
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    • 2015
  • The containment filtered venting system reduces the range of the contamination area around the nuclear power plant by strengthening the integrity of the containment building. In this study, the probabilistic assessment code MACCS2 was used to assess the effect of the CFVS to off-site. The accident source term was selected from a Probabilistic Safety Analysis report of SHINKORI 1&2 Nuclear Power Plant. The three source term categories from 19 STC were chosen to evaluate the effective dose and thyroid dose of residents around the power plant and the dose with CFVS and without CFVS were compared. The dose was calculated according to the distance from the nuclear power plant, so the damage scale based on the distance that exceeds the IAEA criteria for effective dose (100 mSv per 7 days) and thyroid dose (50 mSv per 7 days) were compared. The effective dose reduction rates of the STC-3, STC-4, STC-6 were about 95-99% in the whole range (0~35 km), 96-98% for the thyroid dose. There are similar results between effective dose and thyroid dose. After applying the CFVS, the damage scale that exceeds the effective dose criteria was about 1 km (mean). Especially, the STC-4 damage scale was decreased from 26 km (mean) to 1.2 km (mean) significantly. The damage scale that exceed the thyroid dose criteria was decreased to 2~3 km (mean). The STC-4 damage scale was also decreased significantly as compared to STC-3, STC-6 in terms of effective dose.

STC2 is upregulated in hepatocellular carcinoma and promotes cell proliferation and migration in vitro

  • Wang, Haixiao;Wu, Kuangjie;Sun, Yuan;Li, Yandong;Wu, Mingyu;Qiao, Qian;Wei, Yuanjiang;Han, Ze-Guang;Cai, Bing
    • BMB Reports
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    • v.45 no.11
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    • pp.629-634
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    • 2012
  • The human glycoprotein, stanniocalcin 2 (STC2) plays multiple roles in several tumor types, however, its function and clinical significance in hepatocellular carcinoma (HCC) remain unclear. In this study, we detected STC2 expression by quantitative real-time PCR and found STC2 was upregulated in HCC tissues, correlated with tumor size and multiplicity of HCC. Ectopic expression of STC2 markedly promoted HCC cell proliferation and colony formation, while silencing of endogenous STC2 resulted in a reduced cell growth by cell cycle delay in G0/G1 phase. Western blot analysis demonstrated that STC2 could regulate the expression of cyclin D1 and activate extracellular signal-regulated kinase 1/2 (ERK1/2) in a dominant-positive manner. Transwell chamber assay also indicated altered patterns of STC2 expression had an important effect on cell migration. Our findings suggest that STC2 functions as a potential oncoprotein in the development and progression of HCC as well as a promising molecular target for HCC therapy.

Evaluation of STC schemes for future S-DMB services (차세대 위성 DMB 서비스에 대한 STC 방식의 성능)

  • Park, Un-Hee;Kim, Soo-Young;Kim, Hee-Wook;Ahn, Do-Seob
    • Journal of Satellite, Information and Communications
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    • v.3 no.2
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    • pp.1-6
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    • 2008
  • Space-time codes (STC) can achieve the diversity gain in a multi-path environment without additional bandwidth requirement. Recent study results reported that satellite systems can also achieve this diversity gain by using space-time codes in a cooperative network with terrestrial repeaters. Due to uni-directional nature of satellite DMB services, transmit diversity can be considered as one of the most effective ways to improve the performance. In this paper, we demonstrate various simulations results of STC schemes which can contribute to improve performance of future satellite DMB services. The STC schemes introduced in this paper provides diversity gains by combing independent coded signal from the satellite as well as from the terrestrial repeaters. In addition, we discuss a few points which should be considered to develop and implement these STC schemes.

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Multicasting Algorithm for the STC104 Network (STC104망을 위한 멀티캐스팅 알고리즘)

  • Lee, Hyo-Jong;Jeong, Woo-Chan
    • Proceedings of the Korea Information Processing Society Conference
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    • 2000.10b
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    • pp.1361-1364
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    • 2000
  • STC104 라우터칩은 점대점 방식으로 자료를 전송하도록 설계되어 있어서 하드웨어 기반의 멀티캐스팅을 할 수 없다. 멀티캐스팅을 하기 위해서는 각 노드간의 관계를 파악하여 동시에 데이터를 전송하는 알고리즘을 개발하여 소프트웨어적인 방법을 이용해야 한다. 본 논문에서는 멀티캐스팅 트리를 이용하여 STC104 라우터칩으로 이루어진 그물 구조 망에서 멀티캐스링 전송 알고리즘을 제시하고 그 성능을 실험하였다. 멀티캐스팅 트리를 이용한 전송 성능은 전체 hop수가 적을수록 그리고 발원 노드가 전송할 때 적절히 분산시켜 전송할수록 개선된 성능이 나타났다.

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