Крючков Фундаменталс оф Нуцлеар Материалс Пхысицал Протецтион 2011

allow one both to handle database data directly and get SQL queries running. These object collections are continuously updated with new ones coming out. One of the earliest collections of the kind was DAO (Data Access Objects) [17]. This gave applications the capability to manipulate data which could be communicated with via the SQL query language. Fig. 7.6 presents a DAO-realized object hierarchy.

This collection can be engaged by an application created with the employment of Microsoft Visual Studio for communication with data in formats of popular DBMSs and spreadsheets, e.g. Access or Excel. This also permits the user to get connected to the database with the connection kept by the application that remains open throughout the session. Data from tables or with the aid of SQL queries are copied into datasets (Recordset object). Recordset objects include the sufficient number of methods to allow navigating the dataset and carrying out search functions, that is, doing everything needed to operate data.

DBEngine

Workspace

Database

Fig. 7.6. Hierarchy of objects in the DAO collection of data access object classes

A great deal of data sources, say, those certified for use in MS SQL Server and Oracle NM A&C systems, cannot be however operated directly from DAO. Data in these formats are accessible via a more universal data access technique. ODBC (Open Database Connectivity) is utilized by Microsoft to handle data in various formats.

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ODBC is a set of drivers and interfaces enabling connectivity to various platforms and use of a standard query language for different data management types. To implement access to data storable in different formats, the required drivers are installed into the operating system and a particular database in the format selected is given the logical name of the ODBC set. Thereafter, the application program developer can afford not to think about a particular data presentation because it is enough for him just to employ standard SQL queries to create DAO Recordsets from the databases of any formats. The application can subsequently handle data with the aid of a high-level language and, as required, update data in the database or add new data thereto using standard SQL queries.

DAO was used to create a great deal of database applications. Thus, in particular, it is used for handling data in the LANL-developed computerized NM A&C system (LANMAS) and in COREMAS, its localized version for applications in Russia and other CIS membercountries.

There is another collection of classes to mention in the context of database access objects. This is RDO (Remote Database Objects), which has been optimized to operate in client-server applications. Similarly to DAO, RDO uses ODBC for connections to remote data sources. This collection of object classes was employed by the Kurchatov’s developers to build КИМАКС, a computer-based NM A&C system.

The evolution in ITs has brought about changes to information systems. To begin with, Web-accessible program applications appeared. This required new objects of access to data to be used for Web-applications. Further on, the development of business support electronics brought to life the demand for access to such nonrelational data as electronic documents and letters and others. For support of these capabilities, OLE DB (Object Linking and Embedding), a new technology for accessing all kinds of data, and ADO (ActiveX Data Objects), a new collection of object classes [17], were developed. Unlike ODBC, OLE DB can connect applications to data in any formats. In particular, it can also use ODBC drivers for connections to relational databases. To make use of OLE DB, one needs the services of an OLE DB provider which is to be installed for each type of data sources. OLE DB providers are supplied in the operating system and DBMS delivery packages. Therefore, using ADO with an OLE DB provider for ODBC, one can get the same functionality as with DAO and RDO. Along with this, ADO objects do not form such a stiff hierarchical structure as DAO and will offer more flexibility in handling data in different formats. Fig. 7.7 presents a schematic of the ADO collection of classes.

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Further on, one can operate the data selected using Recordset’s methods and properties. Table 7.1 presents Recordset methods and Table 7.2 presents Recordset basic properties.

Table 7.1

A further evolution of ADO technology was Microsoft.NET, a development platform in the form of ADO.NET [18]. This data access

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model was developed with emphasis placed on its applicability in Web– applications, though, further on, it will operate equally successfully also in traditional Windows applications. There are two basic features in which ADO.NET is different from its predecessor. First, it has the ability to handle data separately from the source of data, and, second, it uses the XML language for data exchange.

The first of these properties is of an extreme significance when operating data in Internet. Each connection to the server consumes its resources. When a certain number of user references to the server are made, it may have its efficiency decreased abruptly. This should be taken into account by those web-applications where the potential number of users is great. Therefore, ADO.NET connects the application to the database for a short time which is just enough to obtain a sample of information or update the database. Communication is interrupted after the data set is delivered or the command is executed, and the data obtained is further processed on the client with no communication with the server.

Use of XML as the data transmission format gives more flexibility to the applications created with the use of ADO.NET, because XML is a technical standard for transmission of data. Where an application operates in Internet/Intranet networks, it becomes no longer dependent on the client platform. Figure 7.8 gives an example of a data access model in ADO.NET.

To realize the concept of data handling separately from the data source, ADO.NET, unlike ADO, forms DataSet rather than Recordset. RecordSet represented a sample of one or more database tables as obtained using an SQL query. DataSet is a partial database copy and may consist of several tables with set relations.

To conclude the overview of data access tools, we shall look at how data objects should be selected to update current and create new applications. It is quite natural that up-to-date data access objects are employed to design new applications based on novel information technologies. However, no object model of access to data should be changed for upgrading the existing applications unless extremely necessary. This model forms the framework of the application/data communication logic so changing this will lead to the requirement of the whole application code to be rewritten.

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Windows NT 4.0 operating system and the MS SQL Server 6.5 and Oracle 7 DBMSs were certified in Russia. Built initially under US standards, many of Russian designs for computerized NM A&C systems had the same software and a similar architecture as the basis. The USA also contributed financially to the establishment of the network infrastructure within the industry, supplied computer technology, trained personnel and funded the creation of new applied software.

Over the decade since then, teams of software engineers have been established within the industry to develop software for its NM A&C systems. The evolution of computerized NM A&C systems for the industry was discussed at the 7th international workshop “Development of the Federal Automated Nuclear Material Accounting and Control System in Russia” held in September 2006, where facts about w hat had been accomplished were made public [19].

At federal level, the regulatory NM accounting and control framework was established and got started, the pattern for submission of reports on NM was defined by Rosatom, the FIS information analysis center was formed and acquisition of information from operators was organized. Separate information systems that, among other things, had tasks in accounting for and control of NM were established at the agency level. The level of organizations, as evidenced by a data survey, had shown, in the previous years, a marked trend towards more vigorous activities in creation and implementation of NM A&C systems.

For all MBAs, computerized NM A&C systems had been installed at 17% of the nuclear industry enterprises, while 27% had established these just for part of their respective MBAs. Another 12% planned the creation and deployment of NM A&C systems as their short term perspective. The rest 44% did not however have plans to establish such systems.

Some enterprises had problems with commissioning computerized NM A&C systems due to lack of sufficient funding and because of getting a late start on the work. There were also certification problems coming from the requirements to systems not having been well defined early in the FIS evolution process, which tended to change occasionally in the process of the system development. By the time, systems had begun to be established at nuclear power plants with computerized accounting and control of NM implemented nearly across the industry.

All certified systems had an individual architecture and had been designed using a variety of development tools. This was by and large the industry’s first generation of computerized NM A&C systems and these continued to evolve. This early generation of systems use base software

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certified to access security class 3, which makes it not possible to use the computer network infrastructure in any other roles within the enterprise, making so the whole of the system more expensive to operate.

The Kurchatov Institute’s КИМАКС [20] was the only system certified to access security class IБ (under Gostekhkomissiya’s 1992 requirements: Chapter 8, Part II), which gave it access to handling data of different secrecy levels. This capability was achieved thanks to its own security system that operated independently of the Windows NT 4.0 security system.

No object-oriented programming and development quality control technologies are practically used to design systems. No use of Webapplications is made as well, except for some systems. The FIS is required to expand further both in scope, so that to encompass, in a longer term, all the enterprises managing nuclear material, and in depth. The latter suggests creation of computerized A&C systems to be certified to access security class II. This, first of all, calls for a shift to new base software.

To be built, the systems of a new generation will require, as a complement to the novel base software, industry software development standards tо secure excellence, upgradeability and cost-effectiveness of systems. This, in turn, brings about the need for advanced IT solutions to the development of database applications. And this is what the industry just embarks upon. In a longer term, a team of software engineers is expected to emerge to create and support, on a pay basis, all corporate NM A&C systems within the industry.

This brings to life the demand for a range of software to meet corporate needs for computerized NM A&C systems. There is an occasional debate about the creation of a product to be shared by all enterprises. The first attempt of having such software introduced was the supply of CoreMAS, a US NM A&C system. This was not successful because of the product having failed to win recognition and find application in Russia.

A versatile product seems to be unfeasible because of the NM handling technologies and the material, as such, varying greatly between enterprises. For most of these, such product will be excessively capable and, accordingly, unreasonably expensive and hard to adopt. Further, we shall review the enterprise demand for computerized NM A&C systems depending on the volumes of the NM held and the way it is handled.

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Requirements to computerized NM A&C systems depending on the enterprise type

Experts at LANL have reviewed the enterprise types that deal with NM. A classification of these has been suggested and proposals made on matching the enterprise type to that of the A&C system. The complexity of an A&C system is defined by the complexity and the number of operations done on NM. Enterprises were reviewed in a spectrum from a small-size storage facility to a high-tech processor. Five enterprise types have been identified.

Type 1. A small storage facility with the number of items below 50. No complex operations. The material is static and items have been in storage

for a long time (up to 10 movements per month). One MBA of about 100 m2.

Type 2. A medium-sized enterprise with the number of items below 500. No complex operations or processes. Key function: storage and moderate activity (up to 100 movements per month). One or two MBAs.

Type 3. A large-sized storage facility with the number of items from 500 to 10000. Several MBAs. A great deal of measurement and inspection. Movements are largely internal (up to 1000 per month). No processing and mechanisms of loss.

Type 4. A medium-sized production facility with many items and a great deal of activity (from 10000 to 20000 items and up to 10000 movements per month). Has several buildings and multiple MBAs. Complex operations on material and more than one mechanism of loss.

Type 5. A large-sized enterprise with a great inventory of items (from 20000 to 100000). The material is very dynamic (up to 50000 movements per month). Mechanisms of losses are very many.

Type 1 enterprises do not have material processing. Items are very few. A simplest paper-and-pen accounting system will do for an enterprise of the kind. One custodian will be enough to make logbook entries.

Type 2 enterprises have material kept in storage most of the time, still may need material to be moved for nondestructive assays. Operations are simple and require a simple accounting system. A paper-and-pen database will do, still an elementary computerized database capable of generating reports with a breakdown by grades is the preferred option. It is enough to have one custodian per MBA.

Type 3 enterprises have more items than a manually operated system can be expected to handle. These, importantly, involve a material change function. A computerized system with one to three workstations will do for

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the case. The database shall be installed in one mainframe networked to other workplace computers.

Type 4 enterprises are major research establishments with noncommercial operations on material. These should have a custodian for each MBA with an access to the workstation. A client/server system is the suggested option. A well–designed database and a co ntrol system to support complex functions are required. The accounting system is required to serve bulk handling operations. The activity is up to 800 movements per day. Reporting functions are diverse. Several persons are needed to operate and maintain the system.

Type 5 enterprises have several custodians, each MBA being specific, but a central database is required. The volume of operations is greater than for Type 4, still functions are the same. This complexity requires a synchronized backup server.

The survey led to the understanding that the industry needed no less than three or four types of computerized NM A&C systems. Material processing and mechanisms of natural process losses this entails are the key factors that influence the complexity of systems.

Two computerized A&C systems were designed by LANL with this approach taken. One is E/Z MAS, a simplified NM A&C system for enterprises of types 1 and 2, as well as for some of type 3 enterprises. The system has been functionally extended, which makes it potentially fit, subject to a bit of an update, for more complex installations. The CoreMAS, a more complex and versatile system, can be used for enterprises of types 4 and 5.

Implementing the whole range of technologies and offering nearly the complete spectrum of operations one can expect of them, the two systems will be looked at hereinafter as examples of computerized NM A&C systems.

СoreMAS, a client/server-based NM A&C system

CoreMAS is a computerized NM accounting and control system built by Los-Alamos National Laboratory (LANL), the USA, based on a classic client-server architecture [21]. The reasons for which this system has been chosen for the study are as follows:

∙ this is a fairly recent system built on a client/server ideology and based on advanced software;

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