Analyzing Google Earth application in a heterogeneous commodity cluster display wall

Nowadays, clusters of interconnected workstations have become a common solution for powering large composite displays, or “cluster display walls”, to visualize high resolution images. Our paper is focused on analyzing a specific cluster display wall developed by Google, named Liquid Galaxy, made up of heterogeneous commodity hardware with different degrees of heterogeneity, running master-slave (Google Earth) and client-server (Quake III Arena) multimedia applications. With this in mind, we define and test different scenarios, representing the behavior of many kinds of users. Our results show that the CPU, memory and network are good enough to execute the client-server application, while, depending on the user behavior, the external network constitutes the bottleneck of the system in Google Earth. So, the master-slave application has focused our attention. Likewise, in order to analyze the users’ point of view when interacting with Google Earth in the Liquid Galaxy, we define a new metric, named Visualization Rate (VR), which enables a relationship to be established between the user experience and the platform performance. In order to set the minimum acceptable value of the VR parameter according to users perception, we carried out different tests with real users. Then, this minimum threshold was compared with the VR value obtained from the automated benchmarking performed afterwards on clusters with different heterogeneity degrees. Finally, we analyzed the VR trend when the Liquid Galaxy is scaled from 3 up to 8 nodes in both the homogeneous and heterogeneous architectures to study the scalability of the system.     

User Satisfaction with Tablet PC Features

Previous studies of tablet personal computers have concentrated on their use in education and healthcare. The current study focused instead on personal usage, investigating how satisfied users are with their own tablets after having used them in their daily lives. The objective was to identify the major features for tablets and to investigate how form factors affect the preference of functions by performing a comparison of iPad1 and Galaxy Tab. Also, gender and ethnicity were analyzed to determine whether they influence satisfaction with the devices. For e‐mail and web browsing functions, users’ ratings showed more satisfaction with the iPad1 since it has a larger display; for the e‐book reader function, users indicated higher satisfaction with the Galaxy Tab. Male users evaluated their devices by the function itself, whereas female users were mainly concerned with aesthetic aspects. Koreans indicated that they were less satisfied with their tablets than were other ethnic groups.     

桌面环境下拼贴显示的自动对准

通过拼贴一组投影仪来构建高分辨率显示系统已成为现在一个较实际的办法.但是,这样的高分辨率显示系统用途有限,因为它们需要在定制的并行机或个人计算机集群上运行一些专门开发的并行形象化程序才能实现.针对个人计算机桌面环境下的任意拼贴显示给出了一种自动对准机制,使得桌面用户可以在其上运行普通的桌面应用软件.该系统包括3个步骤:检测投影仪对齐失准,计算出纠正所需之变换,对桌面环境进行实时的变形.这样就允许用户在运行任何2D,3D或视频程序时无须作任何修改,也无须使用专门的硬件支持.实验结果表明,系统能够获得亚像素级的精度,并且能在系统性能衰减最小的情况下达到实时变形.     

A scientific workflow environment for Earth system related studies

Many separate tasks must be performed to configure, run, and analyze Earth system modeling applications. This work is motivated by the complexities of running a large modeling system on a high performance network and the need to reduce those complexities, particularly for the average user. Scientific workflow systems can be used to simplify these task and their relationships, although how to implement such systems is still an open research area. In this paper, we present a methodology to combine a scientific workflow and modeling framework approach to create a standardized work environment and provide a first example of a self-describing Earth system model. We then show the results of an example workflow that is based on the proposed methodology. The example workflow allows running and analyzing a global circulation model on both a grid computing environment and a cluster system, with meaningful abstractions for the model and computing environment. As can be seen through this example, a layered approach to collecting provenance and metadata information has the added benefit of documenting a run in far greater detail than before. This approach facilitates exploration of runs and leads to possible reproducibility.     

云模型在防止Google Earth地标泄密中的应用

Google Earth给使用者带来方便的同时,也对传统信息安全带来了冲击,应当引起高度注意。设计了Google Earth使用管理软件,其中采用云模型,设立中心服务器,预设了重要监控点的坐标和云参数;当用户点击某个位置,会在中心服务器上生产云图,靠云滴的密集程度来决定是否允许用户标注的地标信息出现在Google Earth上。实验表明,该方法很好地控制了GoogleEarth上重点地点的信息标注,解决了Google Earth的"地标"泄密问题。     

基于Android平台的车辆导航系统设计与实现

该文利用当今流行的Android平台和GPS特性,结合Google Map,设计并实现了一个基于Android平台的车载定位导航终端软件系统,并对整个软件系统的五个主要功能模块进行了详细的分析与研究。该系统经过严格测试,运行稳定可靠,自我定位精确,浏览地图流畅,地址搜索快速,路径跟踪直观,车辆跟踪准确,基本能够满足用户的车辆定位导航服务需求,并且具有广阔的推广应用前景。     

Designing an exergaming system for exercise bikes using kinect sensors and Google Earth

This paper proposes an Exergaming system for exercise bikes. With the assistance of a Kinect device and the proposed body-movement-detection algorithm, exercise bike users are required to perform correct neck and shoulder movements to control the airplane trajectory in Google Earth. They can take a flying tour in the virtual reality provided by Google Earth while riding an exercise bike. According to the experimental results, 95 % of the users in the experiment considered the proposed Exergaming system to be very entertaining; more than 85 % of the users affirmed that the assigned neck and shoulder movements effectively help stretch the muscles in these body parts; the detection rate of the proposed body-movement algorithm was over 90 %. Therefore, the proposed Exergaming system is a good assisting system for exercise bikes.     

Development and evaluation of the HaptiWatch with a smart notification system

In this study, we developed a new type of smartwatch, the HaptiWatch, which has notification functions that are not present in analog watches that lack a high‐resolution display. The HaptiWatch also has a priority‐filtering function that distinguishes notifications by their importance. Notification information is encoded as light and haptic pulses which allow users to recognize the type and importance of the notification without having to see the watch. To evaluate the user experience (UX) of the HaptiWatch's new notification system, a comparative study was conducted together with the notification system of the Samsung Galaxy Gear S3 Frontier, a well‐known smartwatch. The UX evaluation results indicate that the notification system of the HaptiWatch provides an experience that is comparable to that of the Gear S3.     

SW-MPIFT在气象领域的应用

随着集群系统在高性能计算领域的广泛应用,用户对其功能和可靠性的要求也越来越高。文章介绍了一种可以实现保留恢复功能的MPI容错系统,以及该系统在气象模型GRAPES上的应用情况。     

Adaptive middleware supporting scalable performance for high-end network services

Network service-based computation is a promising paradigm for both scientific and engineering, and enterprise computing. The network service allows users to focus on their application and obtain services when needed, simply by invoking the service across the network. In this paper, we show that an adaptive, general-purpose run-time infrastructure in support of effective resource management can be built for a wide range of high-end network services running in a single-site cluster and in a Grid. The primary components of the run-time infrastructure are: (1) dynamic performance prediction; (2) adaptive intra-site resource management; and (3) adaptive inter-site resource management. The novel aspect of our approach is that the run-time system is able to dynamically select the most appropriate performance predictor or resource management strategy over time. This capability not only improves the performance, but also makes the infrastructure reusable across different high-end services. To evaluate the effectiveness and applicability of our approach, we have transformed two different classes of high-end applications—data parallel and distributed applications—into network services using the infrastructure. The experimental results show that the network services running on the infrastructure significantly reduce the overall service times under dynamically varying circumstances.     

Google Earth as a virtual globe tool for Earth science applications at the global scale: progress and perspectives

Research on global environmental change requires new data processing and analysis tools that can integrate heterogeneous geospatial data from real-time in situ measurement, remote sensing (RS) and geographic information systems (GISs) at the global scale. The rapid growth of virtual globes for global geospatial information management and display holds promise to meet such a requirement. Virtual globes, Google Earth in particular, enable scientists around the world to communicate their data and research findings in an intuitive three-dimensional (3D) global perspective. Different from traditional GIS, virtual globes are low cost and easy to use in data collection, exploration and visualization. Since 2005, a considerable number of papers have been published in peer-reviewed journals and proceedings from a variety of disciplines. In this review, we examine the development and applications of Google Earth and highlight its merits and limitations for Earth science studies at the global scale. Most limitations are not unique to Google Earth, but to all virtual globe products. Several recent efforts to increase the functionalities in virtual globes for studies at the global scale are introduced. The power of virtual globes in their current generations is mostly restricted to functions as a ‘geobrowser’; a better virtual globe tool for Earth science and global environmental change studies is described.     

Google Bigtable系统的可信性研究

Bigtable作为Google云计算的一项关键技术,在需要海量的存储要求的Google地图、GoogleEarth、Gmail、Youtube等上面得到了成功的应用.Bigtable是基于GFS和Chubby开发的分布式存储系统,能够处理Google中海量繁杂的数据类型,也能够将不同应用的数据分布地存储到数千台服务器上.文章介绍了Bigtable的数据模型、设计和实现,并引入了随机Petri网对Bigtable系统的可信性进行模拟和量化分析,提出了云计算环境下Key/value存储系统的发展趋势,并从理论上得出Bigtable系统的高可用性和高可靠性.     

基于Linux的超算系统中Windows应用程序运行环境探究

超算系统大多是基于Linux操作系统搭建的,限制了基于Windows操作系统的应用软件使用。此外,超算系统操作的高门槛使不熟悉Linux操作系统的用户望而却步,造成超算系统用户流失。基于Linux超算系统环境,探索兼顾超算系统运维管理便利性的Windows应用程序使用方法。研究通过X11转发、Wine和虚拟化等技术,为用户提供兼容超算作业调度系统Windows应用程序运行环境,同时提供安全、稳定的用户个人文件访问方法。所采用的配置方法与实例,可为具有类似需求的超算中心提供解决方案,从而拓宽用户软件应用范围,提高用户满意度。     

Metrics and techniques for quantifying performance isolation in cloud environments

The cloud computing paradigm enables the provision of cost efficient IT-services by leveraging economies of scale and sharing data center resources efficiently among multiple independent applications and customers. However, the sharing of resources leads to possible interference between users and performance problems are one of the major obstacles for potential cloud customers. Consequently, it is one of the primary goals of cloud service providers to have different customers and their hosted applications isolated as much as possible in terms of the performance they observe. To make different offerings, comparable with regards to their performance isolation capabilities, a representative metric is needed to quantify the level of performance isolation in cloud environments. Such a metric should allow to measure externally by running benchmarks from the outside treating the cloud as a black box. In this article, we propose three different types of novel metrics for quantifying the performance isolation of cloud-based systems.We consider four new approaches to achieve performance isolation in Software-as-a-Service (SaaS) offerings and evaluate them based on the proposed metrics as part of a simulation-based case study. To demonstrate the effectiveness and practical applicability of the proposed metrics for quantifying the performance isolation in various scenarios, we present a second case study evaluating performance isolation of the hypervisor Xen.     

Robust resource allocation in a cluster based imaging system

Recently there has been an increased demand for imaging systems in support of high-speed digital printing. The required increase in performance in support of such systems can be accomplished through an effective parallel execution of image processing applications in a distributed cluster computing environment. The output of the system must be presented to a raster based display at regular intervals, effectively establishing a hard deadline for the production of each image. Failure to complete a rasterization task before its deadline will result in an interruption of service that is unacceptable. The goal of this research was to derive a metric for measuring robustness in this environment and to design a resource allocation heuristic capable of completing each rasterization task before its assigned deadline, thus, preventing any service interruptions. We present a mathematical model of such a cluster based raster imaging system, derive a robustness metric for evaluating heuristics in this environment, and demonstrate using the metric to make resource allocation decisions. The heuristics are evaluated within a simulation of the studied raster imaging system. We clearly demonstrate the effectiveness of the heuristics by comparing their results with the results of a resource allocation heuristic commonly used in this type of system.     

On the pitfalls of bibliographic database searching: comparing successful and less successful users

This article investigates individual factors that determine success and failure in bibliographic database searching. In line with previous research, we hypothesised that the low usability of advanced bibliographic database interfaces (e.g. OvidSP?) would hinder students in implementing their information-seeking knowledge. Furthermore, we assumed high conscientiousness and need for cognitive closure to drive students towards rigidly using such advanced interfaces, even if they overtax them. In a study with 116 psychology undergraduates, 3 types of searchers were identified by means of a cluster analysis: successful database users, unsuccessful database users, and no-database users (e.g. Google Scholar? searchers). Multiple regression revealed the relationship between information-seeking knowledge and search success to be positive for no-database users and negative for unsuccessful database users: unsuccessful database users do not only have trouble putting their information-seeking knowledge into practice; high information-seeking knowledge even impairs their search success, presumably because it makes them use advanced functions that they are not yet able to master. T-tests revealed that unsuccessful users differ from successful users in terms of higher conscientiousness and need for cognitive closure. In conclusion, our results highlight the importance of enhancing database interface usability and underline the crucial role of practical database instruction.     

DICON: interactive visual analysis of multidimensional clusters

Clustering as a fundamental data analysis technique has been widely used in many analytic applications. However, it is often difficult for users to understand and evaluate multidimensional clustering results, especially the quality of clusters and their semantics. For large and complex data, high-level statistical information about the clusters is often needed for users to evaluate cluster quality while a detailed display of multidimensional attributes of the data is necessary to understand the meaning of clusters. In this paper, we introduce DICON, an icon-based cluster visualization that embeds statistical information into a multi-attribute display to facilitate cluster interpretation, evaluation, and comparison. We design a treemap-like icon to represent a multidimensional cluster, and the quality of the cluster can be conveniently evaluated with the embedded statistical information. We further develop a novel layout algorithm which can generate similar icons for similar clusters, making comparisons of clusters easier. User interaction and clutter reduction are integrated into the system to help users more effectively analyze and refine clustering results for large datasets. We demonstrate the power of DICON through a user study and a case study in the healthcare domain. Our evaluation shows the benefits of the technique, especially in support of complex multidimensional cluster analysis.     

基于Nagios的监控数据分析展示平台

基于Nagios已设计开发了中国科学院超级计算环境监控平台,通过监控平台可获取集群的相关运维信息,及时了解各服务器的状况,针对出现的故障问题做出快速响应。监控平台获取的数据受存储方式等因素的限制无法方便地提供给外部使用,本文针对获取的集群数据加工处理并设计开发了获取这些数据的相应接口。开发人员可方便地利用这些接口获取数据并根据自己的需求通过不同的方式进行可视化展示。基于监控接口我们开发实现了一个用于展示超级计算环境运行状况的Show平台。用户或系统管理员可通过科技网通行证登录此平台查看中科院超级计算环境的整体运维信息,同时各管理员可查看自己集群的运维数据。Show平台为用户了解环境以及各集群的运行状况提供了方便的途径。     

Google Earth在森林植被营养元素循环研究中的应用

森林植被营养元素循环是森林生态系统分析中的重要参数.将Google Earth应用在其研究过程中具有重要作用.阐述了Google Earth的主要原理和关键技术,重点分析了KML和Google EarthAPI;设计了Google Earth应用的数据处理流程和系统架构;最后实现了基于Google Earth的贵州龙里森林植被营养元素循环研究系统.     

Representing scientific data sets in KML: Methods and challenges

Virtual Globes such as Google Earth and NASA World Wind permit users to explore rich imagery and the topography of the Earth. While other online services such as map servers provide ways to view, query, and download geographic information, the public has become captivated with the ability to view the Earth’s features virtually. The National Snow and Ice Data Center began to display scientific data on Virtual Globes in 2006. The work continues to evolve with the production of high-quality Keyhole Markup Language (KML) representations of scientific data and an assortment of technical experiments. KML files are interoperable with many Virtual Globe or mapping software packages. This paper discusses the science benefits of Virtual Globes, summarizes KML creation methods, and introduces a guide for selecting tools and methods for authoring KML for use with scientific data sets.