User:Tbarzso
nanoHUB.org
nanoHUB.org is a web-based resource geared toward research, education, and collaboration in the
The nanoHUB hosts approximately 1200 resources[1] which focus on nanotechnology education, including online presentations, courses, learning modules, podcasts, animations, and teaching materials. In addition to more traditional resources, the nanoHUB also offers simulation tools that are accessible from web browsers, allowing individuals and institutions to learn about nanotechnology and to perform experiments via a distributed computing network. The nanoHUB also provides collaboration environment via Workspaces, Online meetings and User groups.
Resources come from over 500 contributors[2] in the nanoscience community, and are utilized by approximately 75,000 users from over 170 countries annually. The majority of users come from academic institutions using nanoHUB as part of their research and educational activities. Users also come form national labs and private industry.
nanoHUB is cited over 260 times in the scientific literature [3][4]. Approximately 60 percent of the citations stem from authors not affiliated with the NCN. Over 200 of the citations refer to nanotechnology research, with over 150 of them citing concrete resource usage. 20 citations elaborate on nanoHUB use in education and over 30 refer to nanoHUB as an example of a national cyberinfrastructure. The goals of this cyberinfrastructure are to enhance the discovery process, as well as enable new venues for discovery throughout the scientific community [5].
nanoHUB resources include:
- Online Seminars
- Online Meeting Rooms
- Virtual Linux Workspaces that facilitate tool development within an in-browser Linux machine
- Online Workshops
- User Groups
- Interactive Simulation Tools
- Lectures, Podcasts & Learning Materials
- Course Curricula for Educators
- News & Events for Nanotechnology
Simulation Tools
nanoHUB provides in-browser simulation tools geared toward nanotechnology, electrical engineering, chemistry, and semiconductor education. nanoHUB tools are available to users a both stand-alone tools, or part of structured teaching and learning curricula comprised of numerous tools. As of 9/01/2008, nanoHUB offers 98 distinct simulation tools[6], and nanoHUB users are welcomed to develop and contribute their own tools for live deployment.
Examples of some tools include:
SCHRED, which calculates the envelope wavefunctions and the corresponding bound-state energies in a typical MOS (Metal-Oxide-
Quantum Dot Lab, which computes the
Bulk Monte Carlo Tool, which calculates the bulk values of the electron
Crystal Viewer helps in visualizing various types of
Band Structure Lab which uses the sp3s*d5 tight binding method to compute E(k) for bulk, planar, and nanowire semiconductors. Using this tool, researchers may compute and visualize the
Infrastructure
nanoHUB utilizes numerous resources for the development, deployment, and presentation of simulations and related materials. These include the hubZERO, the RAPPTURE interface, and Maxwell's Daemon middleware.
HUBzero
nanoHUB is powered by the HUBzero software developed at
HUBzero was created by researchers at Purdue University in conjunction with the NSF-sponsored Network for Computational Nanotechnology. At its core, a hub is a web site built with many familiar open source packages—the
content management system. The HUBzero software builds upon that infrastructure to create an environment in which researchers, educators, and students can access simulation tools and share information. Specifically, a "hub" is defined as a web-based collaboration environment with the following features:- Interactive simulation tools, hosted on the hub cluster and delivered to web browsers
- Simulation tool development area, including source code control and bug tracking
- Animated presentations delivered in Flash format
- Mechanism for uploading and sharing resources
- 5-star ratings and user feedback for resources
- User support area, with question-and-answer forum
- Statistics about users and usage patterns
Users can upload their own content—including tutorials, courses, publications, and animations—and share them with the rest of the community. The hub is designed to be a place where researchers and educators can share data and simulation tools online. Users can launch simulations and post-process results with an ordinary web browser without having to download, compile, or install any code. The tools accessed are interactive, graphical applications that support visualization and comparison of results.
RAPPTURE Toolkit
The Rappture toolkit (RapidAPPlication infrastrucTURE) provides the basic infrastructure for the development of a large class of scientific applications, allowing scientists to focus on their core algorithm. It does so in a language-neutral fashion, so one may access Rappture in a variety of programming environments, including C/C++, Fortran and Python. To use Rappture, a developer describes all of the inputs and outputs for the simulator, and Rappture generates a
Workspaces
A workspace is an in-browser Linux desktop. It provides access to NCN's Rappture toolkit, along with computational resources available on the NCN, Open Science Grid, and TeraGrid networks. One can use these resources to do research, or as a development area for new tools. One may upload code, compile it, test it, and debug it. Once code is working properly in a workspace, it can be deployed as a tool on nanoHUB.
A user can use normal Linux tools to transfer data into and out of a workspace. For example, sftp [email protected] will establish a connection with a nanoHUB file share. Users can also use built-in webdav support on Windows, Macintosh, and Linux operating systems to access theier nanoHUB files on a local desktop.
Middleware
The
One disadvantage of consolidating most communication through the web server is the lack of scalability when too much data is transfered by individual users. In order to avoid a network traffic jam, the web server can be replicated and clustered into one name by means of DNS round-robin selection.
The backend execution hosts that support Maxwell can operate with conventional Unix systems, Xen virtual machines, and a new form of virtualization based on OpenVZ. For each system, a VNC server is pre-started for every session. When OpenVZ is used, that VNC server is started inside of a virtual container. Processes running in that container cannot see other processes on the physical system, see the CPU load imposed by other users, dominate the resources of the physical machine, or make outbound network connections. By selectively overriding the restrictions imposed by OpenVZ, we can synthesize a fully private environment for each application session that the user can use remotely.
References
- ^ http://www.nanohub.org/resources
- ^ http://www.nanohub/org/contributors
- ^ http://www.nanohub.org/citations
- ^ http://connect.educause.edu/Library/EDUCAUSE+Review/CyberinfrastructureInTune/46966
- ^ http://www.cs.purdue.edu/homes/ake/pub/CommunityCyberInfrastructureEnabledDiscovery.pdf
- ^ www.nanohub.org/tools
- ^ https://developer.nanohub.org/projects/rappture/