Материал: Крючков Фундаменталс оф Нуцлеар Материалс Пхысицал Протецтион 2011
∙last name of the person approving the operation.
This data can be seen to include all NM batch parameters.
Documentation of transactions in the above form enables closing of the NM balance in the MBA, estimation of the NM shipper/receiver difference and adherence to regulatory NM accounting and control requirements
3.5. Federal automated NM accounting and control system
The federal automated information NM accounting and control information system (FIS) was established to provide information support to management of nuclear material for peaceful uses and counter illegal circulation thereof. The FIS software was developed by FSUE “TsNIIatominform”.
The FIS is a component of the SSAC and is intended to give information support for governing authorities in charge of planning and management of nuclear material. Among other things, the FIS is intended to:
∙give information support to Rosatom of Russia having powers in implementation of federal-level NM accounting and control;
∙communicate with agency information systems. The FIS is tasked to:
∙create and operate the state NM register;
∙deliver NM data to consumers concerned;
∙give information support to NM exports and imports;
∙give information support to NM transportation tasks.
The FIS is currently based at Rosatom’s Crisis Management Center (CMC) that includes an information and analytical center (IAC).
The IAC supports continuous communication with operators delivering data to FIS. It is exactly to the IAC that corporate information systems report on quantities and movements of NM. The IAC gathers reports on NM, checks these for conformity to specified requirements and regulations, tests data using all kinds of techniques, and, if found conforming to specified requirements, adds data to database. The IAC therefore forms the array of reporting data on NM, operates reference arrays, operates relevant versions of classifiers and communicates actively with data suppliers.
The current stage of the FIS evolution limits the range of data suppliers to Russian operators. To be able to deliver data, operators establish automated NM A&C systems to ensure corporate NM accounting, generation of regulatory NM reports and delivery of these to the FIS.
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The IAC is also responsible for giving information support to the FIS users. It interacts with the FIS information suppliers and defines the required volume and quality composition of data submitted. Most of the information provided by the FIS is consumed by Rosatom executive staff and departments. No interactive user access to the FIS database is presently provided. However, this capability is expected to be made available at subsequent FIS evolution stages, provided information security features are in place.
Initially, the FIS was evolving towards gathering reports on material balance areas. So NM data transmission in the FIS was accordingly based on presentation of data from all MBAs at each enterprise. Operators reporting to the FIS sent in NM inventory listing for MBAs made out as of the reported period ending point and the NM physical inventory reports. This reporting pattern was looked upon as complete. In 1999-2004 the FIS had over 60 MBAs from more than 20 operators connected thereto using this reporting pattern. However, for all attractiveness thereof, this pattern should be understood to be feasible only if a number of conditions are fulfilled, including if corporate automated NM A&C information systems are in place. Besides, it takes quite a time to connect corporate NM A&C systems to the FIS. So, in 2000, a simplified (consolidated) pattern was implemented by Rosatom to connect operators to reports in the FIS. All operators circulating NM were sending annually to the FIS NM Inventory Listings (IL) and NM Inventory Change Reports (ICR) in the form consolidated for respective enterprises.
This dual-form (integrated and consolidated) reporting system had drawbacks (including duplication of NM data flows, loss of time to prepare reports and others), so in 2006 it was decided to switch to a “common reporting system”. As the result, the common corpor ate reporting system was launched into pilot operation in 2007 to replace, subsequently, the integrated and consolidated reporting systems. Common reporting of NMhandling operators hinges on reports based on presentation of data from MBAs merged into so-called reported areas (RA). The reported area is an area administratively established within an organization and formed by one or more MBAs to generate and deliver reports on the MBAs concerned to the SSAC federal level.
The IL RA and IRC RA reports from the area reported on are generated based on IL and ICR reports from the MBAs forming the RA with regard for the material holder and usage mode data.
IL RA/ICR RA reports should be prepared by the operator as a paper document or as its electronic version. An organization’s report coming into
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the FIS IAC is handled at input to result in a data acceptance and error report which is forwarded to the organization concerned. If there are no errors in the organization’s report, the reported data are downloaded into the FIS database. In the event of errors, the IL RA/ICR RA data is subject to adjustment by the operator’s personnel or the FIS IAC personnel as approved by the operator and Rosatom’s respective department.
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CHAPTER 4
STATISTICAL BASIS OF NM ACCOUNTING AND
CONTROL
If formulated in brief, the prime objective of an evolving NM physical protection, accounting and control (PPA&C) system may be said to consist in ensuring confident traceability of NM at all nuclear fuel cycle stages. Ensuring confidence is surely a problem of mathematical statistics [1].
We shall look at how the triad of accounting, control (A&C) and physical protection (PP) of nuclear material (NM) is organized to help achieve the objective in view (Fig. 4.1).
Control |
Accounting |
NM
Physical protection
Fig. 4.1. The NM PPA&C triad
It is perfectly obvious that an efficient solution of the NM nonproliferation and confident traceability task depends on how effective and sufficient each of the triad components (physical protection, accounting and control of NM) is. A number of questions arise, which can be answered only by those who are knowledgeable in probabilistic and statistical methods:
∙how to quantify the efficiency of a nuclear-hazardous facility and nuclear material physical protection system;
∙how often and permissibly accurately a nuclear material shall be controlled;
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∙ how NM accounting measurements shall be properly and sufficiently arranged for?
Use of statistical procedures in inspections and physical inventory taking is dictated by limited time and funds. It happens sometimes that one cannot or finds it economically unreasonable to check all items or all nuclear material in the given material balance area. Statistical methods may however help plan the scope and sequence of sampling so that one could be confident about the characteristics of all material measured from a portion of it.
The prime objective of ensuring traceability of NM is achieved by analyzing and estimating measurement uncertainties and searching for how to bring these down, planning the scope and sequence of sampling, and estimating the statistical significance of measurement discrepancies.
Normally, indeed, the control measurement result deviates from the value declared for the measured characteristic of the nuclear material subject to control. The deviation may be caused either by a measurement error which is determined statistically or by the actually observed difference between the values measured and declared. No final conclusion can be made without the respective statistical analysis done.
Probabilistic and statistical methods do not only enable the efficiency of an accounting and control system to be estimated in quantity terms, but also offer the only means to quantify NM vulnerability, a major characteristic of the physical protection system efficiency, which may be undoubtedly identified as probabilistic.
A large-scale program currently under way to upgrade and improve the state system of accounting for and control of NM envisions to give the state NM A&C system such important feature as extensive use of mathematical statistics methods.
4.1. Basic determination and reduction concepts of probability theory and statistics
Probability theory (PT) and mathematical statistics (MS) stand as a single branch of mathematics. This deals with procedures to solve direct and inverse prediction and decision-making problems. What is the subject matter of MS? One of the simplest definitions is based on the comparison relating to the concept of sampling from a finite universe. Knowing the composition of a universe, one can get a distribution for the composition of a random sample. This is a generic direct PT problem.
Commonly, however, one has to deal with inverse problems when the sample composition is known and it is to be found from this what the
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