A Web-based distributed virtual educational laboratory
Summary (3 min read)
Introduction
- AND MOTIVATIONS RECENT developments in virtual instrument technologies,remote measurement, distributed systems, and interactive educational environments [1], [2] greatly changed the traditional approach to teaching and practical experimentation at any educational level, from technical high schools and undergraduate academic courses through master’s and Ph.D. studies to continuous education and training in the industry.
- This helps in reducing training costs by restricting the tutored activities only to substantial matters.
- Distance learning allows one to limit the costs for continuous training both by providing in-house educational facilities that can be used with a flexible and adaptable schedule and by reducing the time spent in an educational laboratory outside of the company.
A. Educational Goals
- 1) Initial Approach to Instruments, Measurement Procedures, and Applications:.
- The system must take into account undergraduate, graduate, and doctoral students, as well as practitioners from industry.
- Beginners who want to use instruments and measurement methodologies need tools to understand and operate in their specific application field.
- When the student alone is using the simulation environment, educational supports will be appreciated.
- Multimedia pages are attached to each object of the workbench front panel to explain meaning, theory, features, and use of the selected component.
B. User Accessibility
- User’s activities must be performed in a way that is simple and easy to understand, even for people who are not experts in information technologies, also known as 1) User Friendliness.
- 2) Simplicity of Accessing the Laboratory Resources: Access and operation transparency guarantees effective and efficient use.
- For simulated or remote measurement, client computers may be located in any computer classroom, university office, institution, or company, when suited network connections and access authorization are provided to the network of the required educational servers.
- For remote use, computers must be connected to the Internet via transport control protocol/Internet protocol (TCP/IP).
C. Cost Limitation and Hardware Resources Sharing
- 1) Limitation of Laboratory Costs:Virtual instrument technologies, possibly with a limited number of local physical resources, must be used to minimize the costs of laboratory setup and maintenance.
- Acquisition of licenses cannot be delegated to students for cost and political reasons, even if student licenses begin to appear on the market at highly reduced costs.
- Moreover, the limited cost and the restricted installations allow for improving resource updating, thus maintaining the leading edge of educational sites and the adequacy for industrial applications.
- Hands-on experimentation for simple and relatively cheap acquisition systems and application plants are obtained by using dedicated components available in specific laboratories or individual computers.
- Resources must be easily and directly accessible by students, even remotely through the computer network as they were local in the laboratory or even in the computers on which students are working, also known as 4) Shared-Resource Networking.
D. Software Cost and Sharing
- The software developing tools based on graphic, object-oriented programming methods make this job easier and feasible to a wider population, even with limited experience in computer programming.
- 2) Standard Components and Technologies for Simulators: Standard virtual environments for simulation and simulator development make creating and testing new environments simpler and cheaper.
- This approach should be preferred instead of building the whole instrumentation with programming languages and graphic tools since it reduces realization time and cost, increasing quality, correctness, portability, adaptability, and extendibility.
- 3) Engineering the Simulator Components:High quality, accuracy, and correctness of simulation environments can be achieved by using software engineering.
E. Real-Time Operation
- If the system to be measured or controlled is connected to the student’s computer directly through suited acquisition boards, real-time operation of the virtual measurement system is possible.
- This is exactly correct only under some restrictive conditions.
- Practically, analysis and control are still correct even if sampling is not performed contemporaneously on all input signals, but in a time period short enough to allow for considering the input values invariant within this period.
- In control, improper use of remote sensing may lead to system instability and safety problems.
- The interaction with the remote server should be limited to setting up and starting the experiment and, then, to retrieve the results.
F. Distributed System Engineering
- It is relevant for the simulation system and the component library.
- Modularity allows for combining individual components easily to create the workbench or new components, without any need of software development or adaptation.
- The component library must be easily expandable.
- The simulation environment and the component libraries should be portable on different hardware platforms and operating systems, also known as 3) System Portability.
- All these f atures are provided transparently and homogeneously to the users.
G. Cooperative Development, Management, and Maintenance
- 1) Sharing Resources and Experiences Among Universities, Institutions, and Companies:The global communication network and high-level languages allow for allocating simulation and remote acquisition programs on different servers.
- The adoption of de facto standards and widely used development and simulation environments for virtual instrumentation (e.g., LabView by National Instruments) maximizes the opportunities for mutual exchanges of components and experiences.
- Partitioning of design, implementation, and maintenance of the measurement components and plants among several partners allows for assigning tasks to the most suited experts, also known as 2) Specialization and Quality.
- Centralizing design, implementation, and maintenance of resources and servers allows for better control and coordination of the whole system, also known as 3) Centralization for Standardization.
- Other considerations on multiserver systems are found in [4] and [5].
H. Security
- 1) Preservation of Intellectual Rights:The use of simulation environment licenses must be guaranteed and protected from unauthorized accesses.
- This allows any user of the simulation environment for virtual laboratories to simply plug his client computer to the international network and obtain the simulation environment and the instrumentation components directly from the server without any preliminary acquisition of specific software, except the suited access authorization.
- Simulation engine, sampler, and virtual components are created in LabView, a widely used virtual environment for measurement areas produced by National Instruments.
- His research interests are in digital signal processing, estimation, automated instrumentation, and electromagnetic compatibility.
- He received the degree in electrical engineering from Politecnico di Torino, Torino, Italy, in 1969.
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Citations
103 citations
Cites background from "A Web-based distributed virtual edu..."
...…including slides of lectures and exercises [33], [34]; 3) simulation of actual experiments to be executed either remotely or on student’s PC [35], [36]; and, more rarely, 4) remotely accessible laboratories, where the learners can access real instrumentation through a Web page [9], [10], [37]–[39]....
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References
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"A Web-based distributed virtual edu..." refers background or methods in this paper
...In particular, the authors merged the system created for Web-based interaction to create and download virtual benches [3] and the system created for remote measurement [4]–[6]....
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...Other considerations on multiserver systems are found in [4] and [5]....
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...through user validation was adopted [3], [4]....
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...The remote connection manager in the client is an executable program running in parallel to the simulation engine [4], [6]....
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...For all connections, international commercial standard protocols are adopted for the widest access, namely, TCP/IP, file transfer protocol, hypertext transfer protocol, and secure hypert xt transfer protocol (SHTTP) [3], [4]....
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93 citations
"A Web-based distributed virtual edu..." refers background or methods in this paper
...In particular, the authors merged the system created for Web-based interaction to create and download virtual benches [3] and the system created for remote measurement [4]–[6]....
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...components’ definition to realize the virtual workbench [3],...
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...through user validation was adopted [3], [4]....
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...To distribute the engine and the components as well as to create the workbench while protecting the intellectual property, a Web-based interface was adopted [3]....
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...For all connections, international commercial standard protocols are adopted for the widest access, namely, TCP/IP, file transfer protocol, hypertext transfer protocol, and secure hypert xt transfer protocol (SHTTP) [3], [4]....
[...]
76 citations
"A Web-based distributed virtual edu..." refers background in this paper
...RECENT developments in virtual instrument technologies, remote measurement, distributed systems, and interactive educational environments [1], [2] greatly changed the traditional approach to teaching and practical experimentation at any educational level, from technical high schools and undergraduate academic courses through master’s and Ph....
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Frequently Asked Questions (16)
Q2. What protocols are adopted for the widest access?
For all connections, international commercial standard protocols are adopted for the widest access, namely, TCP/IP, file transfer protocol, hypertext transfer protocol, and secure hypertext transfer protocol (SHTTP) [3], [4].
Q3. What are the main features of the simulation environment?
The global communication network and high-level languages allow for allocating simulation and remote acquisition programs on different servers.
Q4. What is the way to achieve portability?
When the system is built by using programming languages, portability is achieved with an absolutely portable language (e.g., nowadays, Java).
Q5. What is the purpose of the authorization manager?
Since components are not able to run without the simulation engine and cannot be stored on the client separately, run-time verification of the user authorization performed by the authorization manager allows for saving their intellectual property.
Q6. What is the real-time behavior of the signal generator?
When signal generators are simulated, the real-time behavior is related only to the characteristics of the simulation environment.
Q7. What are the main goals of the proposed environment?
Experiments have shown that the proposed environment is effective for the two main goals: cost reduction and students’ satisfaction.
Q8. What are the advantages of using software engineering to build a simulator?
4) Reuse of Simulator’s Components: Availability of a component library and use of standard design techniques allow for reusing and enhancing development and costs.
Q9. What is the purpose of the hypertext book?
A hypertext book can be created to guide and support the students with advanced self-training approaches, a complementary tool for traditional teaching.
Q10. How can a student access the educational system?
The educational system can be accessed by using personal computers connected to the international computer network in different locations and with different kinds of connection.
Q11. What is the way to use a computer for simulated or remote measurement?
For simulated or remote measurement, client computers may be located in any computer classroom, university office, institution, or company, when suited network connections and access authorization are provided to the network of the required educational servers.
Q12. How many hours of tutoring were required to perform other experiments?
Students were asked to perform other experiments by using different generators and remotely monitored quantities as homework after regular classes at their convenience: they were required to report results after ten days.
Q13. How can the student use the simulation environment?
On-line help for using the simulation environment and the individual measurement resources can be introduced by using standard programming techniques available in the user interface.
Q14. What are the main objectives of a distributed virtual laboratory for metrology?
Advanced students in metrology areas will be interested in the details of procedures, devices, components, and systems: creating their own instruments and experimenting with their own measurement procedures is interesting but requires the access to suited development systems.
Q15. What is the function of the remote connection manager?
When a client needs a set of samples, a request message with the suited parameters is sent by the virtual component representing the generator to the connection manager.
Q16. What is the way to access the educational system?
Instrument-equipped computers (i.e., computers with acquisition boards) may be anywhere, provided that they are connected to the educational server through Internet and to the system or the plant to be measured.