http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
GPS-free Vehicular Localization System Using Roadside Units with Directional Antennas
Ou Chia-Ho,Wu Bing-Yi,Lin Cai 한국통신학회 2019 Journal of communications and networks Vol.21 No.1
The success of dedicated short-range communications(DSRC) applications depends on an accurate knowledge of the positionsof vehicles within the network. At present, vehicle localizationis generally performed using some form of vehicle-mountedglobal positioning system (GPS). However, GPS signals may not bealways available. Various GPS-free vehicle localization techniquesusing the ranging information, the prior knowledge of the vehicle’sposition, or the special hardware have been proposed for enhancingthe performance of traditional GPS-based methods. Differentfrom the previous approaches, we propose a GPS-free vehicle localizationsystem using roadside units (RSUs) with directional antennaswithout specific hardware support on the vehicle and theassumption of the prior knowledge of the vehicle. In the proposedapproach, each vehicle determines its position using the informationcontained within beacon messages transmitted by neighboringRSUs deployed along the road only. The performance of the proposedlocalization scheme is evaluated by ns-2 simulations and iscompared with those of recent GPS-free and GPS-assisted localizationsystems. The simulation results show that the proposed localizationscheme achieves a higher positioning accuracy than theexisting GPS-free and GPS-assisted schemes. The feasibility of theproposed system for practical applications is further investigatedexperimentally. The experimental results for the positioning accuracyare consistent with those obtained from the ns-2 simulations.
Shao-Hua Lee,Chia-Ying Lin,Ya-Chun Hsu,Yi-Sheng Liu,Ming-Tsung Chuang,Ming-Ching Ou 대한암학회 2020 Cancer Research and Treatment Vol.52 No.1
Purpose Transarterial chemoembolization (TACE) delivers cytotoxic drugs intra-arterially and induces ischemic necrosis by arterial embolization. Embolization is achieved using a variety of agents that differ widely in particle size and range, deformation, and in vivo arterial distribution. The clinical significance of these differences has not been thoroughly characterized. The present study is to compare the efficacy of Embosphere and Embozene microspheres in TACE therapy for hepatocellular carcinoma. Materials and Methods This retrospective study includes 108 hepatocellular carcinoma (HCC) patients who received TACE/doxorubicin with Embozene (70 patients) or Embosphere (38 patients) at a single medical center. Patient outcomes, including liver function, tumor size, tumor response, and complications after treatment, were analyzed. The change in total target lesion size and tumor response was evaluated according to embolization agent and clinical characteristics. Results The postoperative glutamate oxaloacetate transaminase (mean, 194.5 vs. 147.5; p=0.032) and bilirubin (mean, 1.11 mg/dL vs. 0.73 mg/dL; p=0.016) were higher among patients treated with Embozene, the decrease in the number (55.86±25.55% vs. 41.81±38.51%, p=0.027) and size (56.37±25.91 mm vs. 43.44±37.89 mm, p=0.001) of liver tumors relative to baseline was greater in these patients than in those treated with Embosphere. These greater antitumor effects were achieved using lower doses of doxorubicin than for treatment with Embozene. Minor complications were more common among patients treated with Embosphere than with Embozene. Conclusion These results suggest that Embozene is more efficacious than Embosphere for HCC treatment using TACE/doxorubicin.