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

      오늘 본 자료

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

        Phylogenetic and Morphological Identification of the Novel Pathogen of Rheum palmatum Leaf Spot in Gansu, China

        ( Yan Wang ),( Amy O. Charkowski ),( Cuiyun Zeng ),( Tiantian Zhu ),( Huizhen Wang ),( Honggang Chen ) 한국균학회 2016 Mycobiology Vol.44 No.2

        A new leaf spot disease was observed on leaves of Rheum palmatum (Chinese rhubarb) in Northwest China (Gansu Province) starting in 2005. A Septoria-like fungus was isolated and completion of Koch’s postulates confirmed that the fungus was the casual agent of the leaf spot disease. Morphology and molecular methods were combined to identify the pathogen. The fungus produced conidiomata pycnidia and the conidia were 2~5 septate, 61.2~134.1 μm in length and 3.53~5.3 μm in width, which is much larger than the known Spetoria species that infects Polygonaceae species. Phylogenic analysis of the internal transcribed spacer region confirmed that this Septoria-like fungus is within the Septoria genus but distinct from known Septoria species. Together, these morphological and phylogenetic data support that the R. palmatum infecting Septoria strain is a newlydescribed plant pathogenic species.

      • KCI등재

        Monitoring Response to Neoadjuvant Chemotherapy of Primary Osteosarcoma Using Diffusion Kurtosis Magnetic Resonance Imaging: Initial Findings

        Chenglei Liu,Yan Xi,Mei Li,Qiong Jiao,Huizhen Zhang,Qingcheng Yang,Weiwu Yao 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.5

        Objective: To determine whether diffusion kurtosis imaging (DKI) is effective in monitoring tumor response to neoadjuvant chemotherapy in patients with osteosarcoma. Materials and Methods: Twenty-nine osteosarcoma patients (20 men and 9 women; mean age, 17.6 ± 7.8 years) who had undergone magnetic resonance imaging (MRI) and DKI before and after neoadjuvant chemotherapy were included. Tumor volume, apparent diffusion coefficient (ADC), mean diffusivity (MD), mean kurtosis (MK), and change ratio (ΔX) between preand post-treatment were calculated. Based on histologic response, the patients were divided into those with good response (≥ 90% necrosis, n = 12) and those with poor response (< 90% necrosis, n = 17). Several MRI parameters between the groups were compared using Student’s t test. The correlation between image indexes and tumor necrosis was determined using Pearson’s correlation, and diagnostic performance was compared using receiver operating characteristic curves. Results: In good responders, MDpost, ADCpost, and MKpost values were significantly higher than in poor responders (p < 0.001, p < 0.001, and p = 0.042, respectively). The ΔMD and ΔADC were also significantly higher in good responders than in poor responders (p < 0.001 and p = 0.01, respectively). However, no significant difference was observed in ΔMK (p = 0.092). MDpost and ΔMD showed high correlations with tumor necrosis rate (r = 0.669 and r = 0.622, respectively), and MDpost had higher diagnostic performance than ADCpost (p = 0.037) and MKpost (p = 0.011). Similarly, ΔMD also showed higher diagnostic performance than ΔADC (p = 0.033) and ΔMK (p = 0.037). Conclusion: MD is a promising biomarker for monitoring tumor response to preoperative chemotherapy in patients with osteosarcoma.

      • A Novel Zero-Voltage-Switching Push-Pull DC-DC Converter for High Input Voltage and High Power Applications

        Mao Saijun,Wang Huizhen,Yan Yangguang The Korean Institute of Electrical Engineers 2005 KIEE International Transactions on Electrical Mach Vol.b5 No.4

        This paper proposes a novel zero-voltage-switching (ZVS) Push-pull DC-DC Converter for high input voltage and high power applications. This topology utilizes two switches in series to replace one switch in conventional push-pull converter, and two clamping diodes are introduced. The voltage stress of the switches is the input voltage, and the switches can realize ZVS with the use of the leakage inductance of the transformer. Furthermore, secondary full-wave rectifier with a clamping capacitor is used to eliminate the voltage oscillation and spike of the rectifier diodes due to the reverse recovery. Therefore, the electromagnetic interference is reduced effectively. The operation principle of the proposed converter is analyzed theoretically. The output characteristic, ZVS condition and design principle of the clamping capacitor are discussed. Experimental results obtained from a 270V input 2kW prototype with $95.8\%$ high efficiency confirms the design.

      • The development and review of Spatial data index technology

        Shuhua Ren,Huimin Meng,Huizhen Yan 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

        The research in spatial data processing mainly focus on two or multi-dimension data processing, and spatiotemporal data processing on moving objects are now more highlight. Spatial data structure are complicated, so the operations on spatial data will spend more cost. Therefore the optimization on spatial query is the key-point in application, and spatial index structures become the bottle-neck in spatial application, many scholars have done their best and given many methods on the problems. The paper present the review on the development of spatial index methods in recently years, and give a perspective in the spatial index and spatiotemporal index technology.

      • A Compensated Software Reliability Model Based on Unascertained Rational Number

        Yongqiang Zhang,Wen Chen,Huizhen Yan 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

        The software reliability model based on unascertained ration number has unique superiority. It does not have any assumption about software fault process. Moreover, its algorithm is simple, and it avoids derivation of nonlinear equations set. But the characteristic of the algorithm itself determines that the estimation of this model is the pessimistic estimation. In this view, this paper makes some improvement to this model, and puts forward the compensated software reliability model based on unascertained rational number, which make the model have wider applicability and suit the reliability growth feature better.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼