RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
        • 등재정보
        • 학술지명
        • 주제분류
        • 발행연도
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • SCIESCOPUSKCI등재

        Performance Analysis of Coordinated Cognitive Radio Networks under Fixed-Rate Traffic with Hard Delay Constraints

        Castellanos-Lopez, S. Lirio,Cruz-Perez, Felipe A.,Rivero-Angeles, Mario E.,Hernandez-Valdez, Genaro The Korea Institute of Information and Commucation 2014 Journal of communications and networks Vol.16 No.2

        Due to the unpredictable nature of channel availability, carrying delay-sensitive traffic in cognitive radio networks (CRNs) is very challenging. Spectrum leasing of radio resources has been proposed in the so called coordinated CRNs to improve the quality of service (QoS) experienced by secondary users (SUs). In this paper, the performance of coordinated CRNs under fixed-rate with hard-delay-constraints traffic is analyzed. For the adequate and fair performance comparison, call admission control strategies with fractional channel reservation to prioritize ongoing secondary calls over new ones are considered. Maximum Erlang capacity is obtained by optimizing the number of reserved channels. Numerical results reveal that system performance strongly depends on the value of the mean secondary service time relative to the mean primary service time. Additionally, numerical results show that, in CRNs without spectrum leasing, there exists a critical utilization factor of the primary resources from which it is not longer possible to guarantee the required QoS of SUs and, therefore, services with hard delay constraints cannot be even supported in CRNs. Thus, spectrum leasing can be essential for CRN operators to provide the QoS demanded by fixed-rate applications with hard delay constraints. Finally, the cost per capacity Erlang as function of both the utilization factor of the primary resources and the maximum allowed number of simultaneously rented channels is evaluated.

      • KCI등재

        A Meta-Analysis of Association between Remdesivir and Mortality among Critically-Ill COVID-19 Patients

        Razzack Aminah Abdul,Hassan Syed Adeel,Pasya Sai Kumar Reddy,Erasani Greeshma,Kumar Sham,Rocha-Castellanos Dario Missael,Lopez-Mendez Alfonso,Razzack Sarah Abdul 대한감염학회 2021 Infection and Chemotherapy Vol.53 No.3

        Background: The World Health Organization guidelines did not make a recommendation on use of remdesivir based on disease severity. Little is known regarding effectiveness of remdesivir in critically ill coronavirus disease 2019 (COVID-19) patients. This has led to a state of dilemma for doctors leaving them skeptical of whether they should continue to recommend the drug or not. Materials and Methods: A systematic search adhering to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines was conducted from inception until February 20, 2020. Electronic bibliographic databases (PubMed, Cochrane database, Scopus, Embase) were included. Using dichotomous data for select values, the unadjusted odds ratios (ORs) were calculated applying Mantel Haenszel (M-H) using random-effects model. The primary outcome of interest was all-cause mortality in ventilated and nonventilated patients. Results: The Remdesivir arm was associated with similar rates of 28-day all-cause mortality (OR: 0.93, 95% confidence interval [CI]: 0.80 - 1.08; P = 0.33). Remdesivir was not found to be favorable for ventilated patients. Non ventilated COVID-19 patients showed a significant lower in-hospital mortality rate as compared with patients requiring mechanical ventilatory support (OR: 6.86, 95% CI: 5.39 - 268.74; P <0.0001). Conclusion: Non-ventilated patients were associated with significant lower all-cause mortality rates. Prudent use of remdesivir is recommended in critically ill COVID-19 patients.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼