VMware是VMware公司出品的一个多系统安装软件。利用VMware可以使一台电脑的部分硬盘和内存虚拟出若干台机器,每台机器均可运行单独的操作系统而互不干扰,这些"新"机器各自拥有独立的CMOS、硬盘和操作系统,操作者可以像使用...VMware是VMware公司出品的一个多系统安装软件。利用VMware可以使一台电脑的部分硬盘和内存虚拟出若干台机器,每台机器均可运行单独的操作系统而互不干扰,这些"新"机器各自拥有独立的CMOS、硬盘和操作系统,操作者可以像使用普通机器一样对它们进行分区、格式化、安装系统和应用软件等操作,还可以将这几个操作系统联成一个网络。本文以Red Hat Linux的安装为例,简单介绍了VMware Workstation在计算机操作系统课教学中的应用。展开更多
Objective: The aim of our study was to determine the efficiency and effectiveness of picture archiving and communication system(PACS) workstation in detecting the sizes and attenuation of malignant solitary pulmonary ...Objective: The aim of our study was to determine the efficiency and effectiveness of picture archiving and communication system(PACS) workstation in detecting the sizes and attenuation of malignant solitary pulmonary nodules(SPNs). Methods: Forty patients with malignant SPNs(diameter ≤ 3 cm) underwent multidetector-row computed tomography(CT) of the chest in a single-breath-hold technique. The raw data were acquired with a collimation of 0.625 mm. The diameters and attenuation of malignant SPNs were measured on PACS and CT workstation respectively. The diameter was defined as the average value of the anteroposterior, lateral and superoinferior diameters on CT scans obtained with a mediastinal window setting. The superoinferior diameters were measured on MPR image. The diameters and attenuation of malignant SPNs and spending time in measuring were recorded. Results: The diameters of malignant SPNs measured on a PACS and CT workstation were 2.09 cm ± 0.87 cm, 2.07 cm ± 0.79 cm, respectively. There was not statistically significant difference in the diameters of malignant SPNs between that measured on a PACS workstation and that on a CT workstation(t = 1.580, P = 0.210 > 0.05). The attenuation of malignant SPNs measured on a PACS and CT workstation were 40.15 HU ± 7.53 HU, 39.99 HU ± 8.13 HU, respectively. There was not statistically significant difference in the attenuation of malignant SPNs between that measured on a PACS workstation and that on a CT workstation(t = 1.008, P = 0.298 > 0.05). The spending time in measuring on a PACS and CT workstation were 55 s ± 4.03 s, 56 s ± 3.95 s, respectively. No statistically significant difference was found in spending time in measuring between that on a PACS workstation and that on a CT workstation(t = 0.958, P = 0.315 > 0.05). Conclusion: The efficiency and effectiveness of PACS workstation is as same as those of CT workstation in detecting the sizes and attenuation of malignant SPNs. It is suggested that the size and attenuation of malignant SPNs are measured on a PACS and CT workstation.展开更多
The real problem in cluster of workstations is the changes in workstation power or number of workstations or dynmaic changes in the run time behavior of the application hamper the efficient use of resources. Dynamic l...The real problem in cluster of workstations is the changes in workstation power or number of workstations or dynmaic changes in the run time behavior of the application hamper the efficient use of resources. Dynamic load balancing is a technique for the parallel implementation of problems, which generate unpredictable workloads by migration work units from heavily loaded processor to lightly loaded processors at run time. This paper proposed an efficient load balancing method in which parallel tree computations depth first search (DFS) generates unpredictable, highly imbalance workloads and moves through different phases detectable at run time, where dynamic load balancing strategy is applicable in each phase running under the MPI(message passing interface) and Unix operating system on cluster of workstations parallel platform computing.展开更多
In recent years, high performance scientific computing under workstation cluster connected by local area network is becoming a hot point. Owing to both the longer latency and the higher overhead for protocol processin...In recent years, high performance scientific computing under workstation cluster connected by local area network is becoming a hot point. Owing to both the longer latency and the higher overhead for protocol processing compared with the powerful single workstation capacity, it is becoming severe important to keep balance not only for numerical load but also for communication load, and to overlap communications with computations while parallel computing. Hence,our efficiency evaluation rules must discover these capacities of a given parallel algorithm in order to optimize the existed algorithm to attain its highest parallel efficiency. The traditional efficiency evaluation rules can not succeed in this work any more. Fortunately, thanks to Culler's detail discuss in LogP model about interconnection networks for MPP systems, we present a system of efficiency evaluation rules for parallel computations under workstation cluster with PVM3.0 parallel software framework in this paper. These rules can satisfy above acquirements successfully. At last, two typical synchronous,and asynchronous applications are designed to verify the validity of these rules under 4 SGIs workstations cluster connected by Ethernet.展开更多
文摘VMware是VMware公司出品的一个多系统安装软件。利用VMware可以使一台电脑的部分硬盘和内存虚拟出若干台机器,每台机器均可运行单独的操作系统而互不干扰,这些"新"机器各自拥有独立的CMOS、硬盘和操作系统,操作者可以像使用普通机器一样对它们进行分区、格式化、安装系统和应用软件等操作,还可以将这几个操作系统联成一个网络。本文以Red Hat Linux的安装为例,简单介绍了VMware Workstation在计算机操作系统课教学中的应用。
文摘Objective: The aim of our study was to determine the efficiency and effectiveness of picture archiving and communication system(PACS) workstation in detecting the sizes and attenuation of malignant solitary pulmonary nodules(SPNs). Methods: Forty patients with malignant SPNs(diameter ≤ 3 cm) underwent multidetector-row computed tomography(CT) of the chest in a single-breath-hold technique. The raw data were acquired with a collimation of 0.625 mm. The diameters and attenuation of malignant SPNs were measured on PACS and CT workstation respectively. The diameter was defined as the average value of the anteroposterior, lateral and superoinferior diameters on CT scans obtained with a mediastinal window setting. The superoinferior diameters were measured on MPR image. The diameters and attenuation of malignant SPNs and spending time in measuring were recorded. Results: The diameters of malignant SPNs measured on a PACS and CT workstation were 2.09 cm ± 0.87 cm, 2.07 cm ± 0.79 cm, respectively. There was not statistically significant difference in the diameters of malignant SPNs between that measured on a PACS workstation and that on a CT workstation(t = 1.580, P = 0.210 > 0.05). The attenuation of malignant SPNs measured on a PACS and CT workstation were 40.15 HU ± 7.53 HU, 39.99 HU ± 8.13 HU, respectively. There was not statistically significant difference in the attenuation of malignant SPNs between that measured on a PACS workstation and that on a CT workstation(t = 1.008, P = 0.298 > 0.05). The spending time in measuring on a PACS and CT workstation were 55 s ± 4.03 s, 56 s ± 3.95 s, respectively. No statistically significant difference was found in spending time in measuring between that on a PACS workstation and that on a CT workstation(t = 0.958, P = 0.315 > 0.05). Conclusion: The efficiency and effectiveness of PACS workstation is as same as those of CT workstation in detecting the sizes and attenuation of malignant SPNs. It is suggested that the size and attenuation of malignant SPNs are measured on a PACS and CT workstation.
基金Natural Science Foundation of China (No.60 173 0 3 1)
文摘The real problem in cluster of workstations is the changes in workstation power or number of workstations or dynmaic changes in the run time behavior of the application hamper the efficient use of resources. Dynamic load balancing is a technique for the parallel implementation of problems, which generate unpredictable workloads by migration work units from heavily loaded processor to lightly loaded processors at run time. This paper proposed an efficient load balancing method in which parallel tree computations depth first search (DFS) generates unpredictable, highly imbalance workloads and moves through different phases detectable at run time, where dynamic load balancing strategy is applicable in each phase running under the MPI(message passing interface) and Unix operating system on cluster of workstations parallel platform computing.
文摘In recent years, high performance scientific computing under workstation cluster connected by local area network is becoming a hot point. Owing to both the longer latency and the higher overhead for protocol processing compared with the powerful single workstation capacity, it is becoming severe important to keep balance not only for numerical load but also for communication load, and to overlap communications with computations while parallel computing. Hence,our efficiency evaluation rules must discover these capacities of a given parallel algorithm in order to optimize the existed algorithm to attain its highest parallel efficiency. The traditional efficiency evaluation rules can not succeed in this work any more. Fortunately, thanks to Culler's detail discuss in LogP model about interconnection networks for MPP systems, we present a system of efficiency evaluation rules for parallel computations under workstation cluster with PVM3.0 parallel software framework in this paper. These rules can satisfy above acquirements successfully. At last, two typical synchronous,and asynchronous applications are designed to verify the validity of these rules under 4 SGIs workstations cluster connected by Ethernet.
