IAEA-142

GUIDELINESDEVELOPMENT

MAINTENANCETHESAURUS

DECEMBER 1971 EDITIONPREPARED BY

J. HEIJNEN AND C. TODESCHINI

A TECHNICAL REPORT PUBLISHED BY THEINTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1971

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FOREWORD

The Board of Governors of the International Atomic Energy Agency(IAEA), meeting in February 1969 in Vienna, authorized the establishmentof the International Nuclear Information System (INIS).

INIS is a mission-oriented system in nuclear science and thepeaceful applications of nuclear technology. It is highly decentralizedfor both input preparation and retrieval operations. INIS outputproducts are multi-purpose; both computer tapes and a printed biblio-graphy are available.

Optimal use of computers for handling information, especiallyin a highly decentralized environment, requires a high degree ofconsistency and compatibility in the preparation of input. The IAEApublishes a set of standards and rules called: The INIS Reference Series.They are based on long-term experience with other information systemsand were prepared to meet the decentralized and specialized INISrequirements. INIS, as a mission-oriented system, seeks to interfacewith other mission- or subject-oriented information systems. In orderto avoid duplication in the work done for subject-oriented systems, itis expected that INIS will attempt to link itself with such systems inan effort to interchange or exchange input or output products. Thisrequires a high degree of compatibility.

This is in keeping with the UNISIST concept to develop and promotethe idea of a world-wide network of information systems.

INIS may be considered as the first decentralized world-widemission-oriented information system serving as an example for thefeasibility of the UNISIST concept. The IAEA fosters this development

in various ways, such as the careful preparation and maintenance ofits controlled vocabulary to enhance subject retrieval.

Draft guidelines for the development and maintenance of theINIS Thesaurus ' were drawn up by the IAEA Secretariat and with minormodifications were approved and used by the INIS Centre of theCzechoslovak AEC; by Le Service Central de Documentation, CEA de Prance;by the Division of Technical Information Extension of the US AEC andthe Information Research Group, Lawrence Berkeley Laboratory,University of California, in a systematic study of the INIS Thesauruslasting from March to September 1971• Alterations and improvements inthe guidelines resulting from the systematic thesaurus study areincluded in the present document. These guidelines were approved bythe first meeting of the Working Group on the INIS Thesaurus andRelated Technical Problems which met in Vienna on 2-4 November 1971-This approval was confirmed by the INIS Advisory Committee at itsVienna meeting on 18-19 November 1971•

Acknowledgement

The authors would like to thank members of the INIS Section,headed by Mr. Zhan Turkov, for their comments and suggestions for theimprovement of this document. Furthermore we are most grateful to:Messrs J. Hybner, J. Helbich and 0. Vojtech of the Czechoslovak AEC;Mr. J. lung, of Le Service Central de Documentation, CEA de France;Mr. D. Davis of the Division of Technical Information Extension of theUS AECj and to Mrs. J. Herr of the Information Research Group,Lawrence Berkeley Laboratory University of California, for theirvaluable contributions to these guidelines.

1) lAEA-INIS-r? (INIS: Thesaurus)

I. INTRODUCTION

INI S requires that for each piece of literature reported to thesystem both the bibliographical description and a set of descriptors toidentify the subject content of the document be provided. It was recom-mended by the Study Team which initially designed INIS that co-ordinateindexing be used for the system

Co-ordinate indexing of full-text documents offers high precisionin indexing, i.e. both high quality and consistency, and consequentlygood retrieval performance. For high-quality indexing it is aprerequisite that indexers have good subject knowledge. In order toachieve high consistency the controlled vocabulary (thesaurus) fromwhich descriptors are to be selected needs an understandable andpredictable structure and clear presentation. The easier it is for anindexer to be led to the appropriate terminology in the thesaurus,the more likely he will produce consistent indexing.

Therefore the criteria on which the thesaurus is constructedshould be unambiguous and clear to all contributors and users of INIS.Retrieval operations on INIS output tapes will be performed on adecentralized basis by participants in INIS. Indexers as well asretrievers preparing query profiles using INIS descriptors for SDI orretrospective searches will be scattered all over the world. Further-more indexers at the different centres are not necessarily thepersons preparing query profiles for mechanical searches. Advancedcomputer techniques will make it possible for anyone wishing toretrieve certain information to go to an on-line console and type inhis own query profile, provided the thesaurus from which he selects hisdescriptors is structured in such a way that all concepts containedare unambiguously defined and their presentation self-evident. Whether

1) "INIS Study Team Report", IAEA,

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a retriever is an experienced indexer or someone with no knowledge ofinformation science at all, he should not be flooded with informationnot directly pertinent to his question while doing a machine search.An information system will stand or fall with the appeal it has toits users.

The main reasons for establishing these guidelines are:1) to set out clear and unambiguous criteria on which the

structure of the terminology in the INIS Thesaurus is based;

2) to allow the INIS Centre in Vienna to perform a highlycentralized maintenance of the INIS Thesaurus;

3) to have a broad basis for compatibility between the INISThesaurus and the controlled vocabularies of other mission- orsubject-oriented information systems, existing or planned.(See: Foreword)

The latter is also the reason why the Guidelines for theDevelopment and Maintenance of the INIS Thesaurus follow closely thosedeveloped by UNESCO ; Guidelines for the Establishment and Developmentof Monolingual and Technical Thesauri for Information Retrieval.Continued reference was also made to the Guidelines commonly knownas the EJC/Project IEX guidelines !Thesaurus Rules and Conventionswhich are much in parallel with the UNESCO guidelines. On questionsof the hierarchy of the terminology, reference was also made to a

2)letter by Mr. Eugene Wall to the editor of the ASÍS Journal .

In the present document the term "descriptor" will be usedexclusively to signify an accepted term and to differentiate it froma forbidden term or non-descriptor.

The examples used in this document have not necessarily beentaken from the INIS Thesaurus.1) Thesaurus of Engineering and Scientific Terms, US Department of

Defense, Report No. AD 672 000, 196?, pages 673-6792) Journal of the American Society for Information Science - Sept. -Oct.

1970, pages Jft-JJ*- 6 -

II. THE THESAURUS STRUCTURE

The most important function of a thesaurus is to serve as a toolin information retrieval. Descriptors chosen from the thesaurus mustgive clear indications of the information and date content of adocument. To do this their meaning must be well defined arid completelyunambiguous. This semantic definition must be provided in the thesaurusby means of the structure which is given to the terminology. Itbecomes imperative therefore, that the interrelationship betweenindividual descriptors be brought clearly into evidence.

These interrelationships are of three types: preferential;hierarchical; affinitive. All three have the property of reciprocity,i.e. when two or more descriptors are related in any way, reciprocalentries should be provided. It is one of the purposes of theseguidelines to lay down the criteria which govern the existence orvalidity of an interrelationship between any two descriptors withinany of the three types mentioned above.

Cross references

Interrelationships among terms will be shown by cross referenceswhich are here grouped according to the three types:

Cross References _________Symbol____________TypeUSEUSED FORSEE ... OR

SEEN PORBROADER TERMNARROWER TERM

USEUPSEEORSPBTNT

Preferential

Hierarchical

RELATED TERM RT Affinitive

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1. Preferential relationships

These cross references are employed to refer from a forbiddenterm to a descriptor(s) and vice versa. They are used when themeaning of descriptors overlap substantially; where differentspellings of the same word exist; for synonyms, antonyms andhomonyms and, in general, wherever a choice has been made betweena number of terms, all of which are included in the thesaurus display.

a) USE ReferenceThe USE reference is intended to lead users of the thesaurus froma forbidden term to a descriptor(s) which must be used in its stead.This "Exclusive" reference is employed in a variety of situations:

i) to indicate a preferred synonyme.g. -c olumbium

USE NIOBIUM

ii) to indicate a preference between spelling variationse.g. -sulphur

USE SULFUR

iii) to expand or explain abbreviationse.g. -esr

USE ELECTRON SPIN RESONANCE

iv) to express concepts which can be considered synonyms forpurposes of indexing and retrievale.g. -maxwell-boltzmann distribution

USE BOLTZMANN STATISTICS

v) to bring together different viewpoints of a conceptualcontinuume.g. -softness

USE HAREWESS

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vi) to reflect current terminology, eliminate jargon or exercisea choice for semantic or other reasonse.g. -electric condensers

USE CAPACITORS

-cosmosUSE UNIVERSE

vii) to refer the variations in proper name terminology to onechoicee.g. -fermi diagram

-fermi-kurie plot-kurie plot

USE FERMI PLOT

There are instances other than of the types exemplified above,when a term is entered as a forbidden term either because it isconsidered too specific, or to reduce the number of precoordinateddescriptors or because it is considered poor terminology. In thesecases the forbidden term is referred, whenever possible, to a moregeneral descriptor(s) which is a correct broader term in the sense ofsection 2. below (Hierarchical relationships)

e.g. -dark repairUSE BIOLOGICAL REPAIR

-radioactive gaseous wastesUSE GASEOUS WASTESAND RADIOACTIVE WASTES

b) USED POR ReferenceThe USED FOR reference (UP) is the mandatory reciprocal of the USEreference and accompanies the descriptor to which the USE referencereferse.g. CAPACITORS

UP -electric condensers

c) SEE Reference

The SEE reference is primarily intended to resolve the difficultyof homographie terms. Since the accurate indication of informationcontent and hence pertinent retrieval cannot permit more than onemeaning to a descriptor, homonyms are not allowed. The thesauruseither identifies which of the possible meanings is the only oneaccepted (e.g. by a scope note) or better the homonym is enteredas a forbidden term and the SEE...OR references invite the user toselect among the two or more alternatives the specific meaning,more clearly spelled out, which he has in mind.

e.g. -processingSEE DATA PROCESSINGOR FABRICATIONOR ORE PROCESSINGOR REPROCESSINGOR WASTE PROCESSING

In some cases the forbidden term may have only one SEE referencewhere the preferred term may or may not be appropriate.

e.g. -level densitySEE ENERGY LEVELS

d) SEEN FOR Reference

The SEEN FOR reference (SP) is the mandatory reciprocal of the SEEreference and accompanies the descriptor to which the SEE referencerefers.

e.g. FABRICATIONSF -processing

e) Alternative methods of resolving the difficulty posed by homographieterms are an extensive use of qualifiers and of scope notes. Thesetwo methods are used in the INIS Thesaurus whenever possible inpreference to the SEE reference. They are discussed in the sectiondevoted to homonyms ( See IH/l/b) .

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2. Hierarchical relationships

Hierarchical relationships are used to exhibit relative degreesof specificity within a category of descriptors all of which belong toa particular generic group. This relationship is not based upon thepossible use or application of an entity, but on the position of theconcept within a given class of concepts. Certain terras may be membersof more than one hierarchical chain. Where any hierarchy has more thantwo levels, the cross-reference for all levels are completed for eachdescriptor. All concepts which are subdivisions of a broader conceptshould form part of a hierarchical chain.

a) BROADER TERM Reference

The BROADER TERM reference (ET) is employed to refer from adescriptor representing a member of a class (or classes) of conceptsto any descriptor(s) in the thesaurus representing that class orclasses.

e.g. HARDNESSBT mechanical properties

Por each BROADER TERM reference there must also be a reciprocalNARROWER TERM reference.

b) NARROWER TERM Reference

The NARROWER TERM reference (NT) is the reciprocal of theBROADER TERM reference and is employed to refer from a descriptorsymbolizing a concept class to all descriptors symbolizing conceptsthat are members of that class.

e.g. MECHANICAL PROPERTIESNT HARDNESS

For each NARROWER TERM reference there must also be a reciprocalBROADER TERM reference.

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c) The validity of hierarchical relationships must be clearlyestablished in each instance. The criterion to be used should bethat of class membership, i.e. a valid hierarchical relationshipexists only if the NT is a subclass of the HT. It should beexplicitly said that a descriptor could be a subclass of more thanone BT1 simultaneously.

The part-whole relationship is not a legitimate hierarchicalrelationship. The class membership rule of hierarchies is waivedonly for part-whole relationships between geographical subdivisionsof a political nature and between anatomical parts.

e.g. AUSTRIABT1 europe

STCMACHBI1 gastrointestinal tract

d) Hierarchies in the terminology are not truncated but in all instancesare carried through to the highest level of generality usingterminology present in the thesaurus. Although this will lead tohigh frequency of usage figures for some descriptors as a resultof automatic generic posting, this is not an unduly adverse resultand useful retrieval can be made with the more general terms in co-ordination with specific ones.

e) Truncated display

There are a number of descriptors in the thesaurus which are in thenature of cumulative terms, each representing a class consistingof a large number of specific descriptors. Each one of thespecific descriptors is a narrower term of the cumulative descriptorin question, e.g. the descriptor RADIOISOTOPES has over l400specific radioisotopes as narrower terms. Since long lists ofnarrower terms of this type displayed with these cumulative

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descriptors are not of great usefulness to indexers but moreso to retrievers formulating query profiles, the display ofthe hierarchies is truncated in the printed version of thethesaurus. This means that whenever one of the specificnarrower terms is used in indexing the cumulative broader termis automatically added by the computerized up-posting procedureas with all other descriptors used in indexing, but the specificterms do not appear as narrower terms in the display of thecumulative term in the printed thesaurus. Those descriptorswhose hierarchical display is truncated in this way are identifiedby an asterisk (*) at the level below which no narrower terms are listedand have a scope note reading:

(For specific terms, consult the Appendix.)

The complete hierarchical display for a few descriptors whosehierarchies are truncated in the printed thesaurus as describedabove, are given with full listings of narrower terms in theAppendix to the thesaurus.

Example, thesaurus display:

* YEARS LIVING ISOTOPES(For specific terras,consult the Appendix.)

Example, thesaurus appendix display:

YEARS LIVING ISOTOPESBT1 radio!sotopesNT1 ACTINIUM 22?NT1 ALUMINIUM 26NT1 AMERICIUM 24lNT1 AMERICIUMETC.ETC.

Another kind of truncation is applied to long hierarchieshaving many subclasses, each consisting of a high number ofdescriptors. In order to save space, some of these long trees havebeen truncated in the printed version of the thesaurus at theNT1, or NT2, or NT5 level, etc.

Contrary to the previously described truncation, all narrowerterms in long hierarchies are very useful to both indexers andretrievers and should thus be found in the thesaurus itself.

e.g. REACTORS*NT1 BREEDER REACTORS*NTI DUST COOLED REACTORS*NT1 ENRICHED URANIUM REACTORSETC.ETC.

In our example the narrower terms to the descriptors preceded by anasterisk (*) are not printed in the display of REACTORS. However bylooking up the descriptor marked with an asterisk in the directlisting in the thesaurus one will find all narrower terms belongingto that descriptor.

e.g. BREEDER REACTORSBT1 reactorsNT1 FER TYPE REACTORSNT2 AIPFR REACTORNT2 BELOYARSK-3 REACTORETC.ETC.

or: DUST COOLED REACTORSBT1 reactors

or: ENRICHED URANIUM REACTORSHT1 reactorsNT1 ACPR REACTORNT1 ADIEKA-1 REACTORNT1 AFSR REACTORETC.ETC.

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This kind of truncation can be performed on each level ofspecificity of a hierarchy.

Truncated descriptors in long hierarchies for which narrowerterms can be found in the thesaurus itself have no scope notes.

Affinitive relationships

The affinitive relationship is employed to refer from onedescriptor to others that are related in concept but are neitherconsistently hierarchically nor preferentially related.

a) RELATED TERM Reference

The RELATED TERM reference (RT) is employed as a guide froma given descriptor to other descriptors if it is believed that theuser, when examining one descriptor, may be usefully reminded of theexistence of the other.

Related term references may be used to identify:i) descriptors that are related in meaning or concept including

those in different hierarchical chains.

ii) descriptors that are near synonyms

e.g. FUEL CANSRT fuel elements

iii) descriptors that have view point interrelationships, such asrelationships based on usage

e.g. BREATHRT air

iv) descriptors representing concepts bearing a part-wholerelationship to each other.

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4. Scope notes

Scope notes may not only be used for the purpose as citedunder III/1/d of this document, but can considerably contribute toreinforcing the cross-reference structure of the thesaurus. Besidesthe definition of a term, the scope note could consist of directivesto consult other hierarchies in the thesaurus, which have developedas a result of the restriction in usage of the annotated descriptor.

e.g. BREAKDOWN(Limited to electric discharge phenomena.See also CLEAVAGE or DECOMPOSITION.)

In case a scope note is also used for cross-reference toother concepts in the thesaurus, those descriptors are printed inupper case in the text of the annotation.

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III. SELECTION OP CANDIDATE DESCRIPTORS

General

Descriptors in general consist of terms related to discreteconcepts encountered in the subject field under consideration and inpertinent marginal areas. In the INIS subject control system allindex terms are equally referred to as descriptors.

Descriptors should succintly summarize concepts in as fewwords as possible, preferably one. Grammatical connections such asprepositions or articles should be avoided whenever possible.

In evaluating the utility of candidate descriptors, referenceshould be made to their:

1) frequency as encountered in the literature or in theexisting stocks of information;

2) anticipated incidence in retrieval inquiriesj5) relationship to descriptors already accepted;4) appropriateness and authenticity as current terminology

in the discipline concerned;5) effectiveness and expediency in connoting and denoting

the particular concept.

None of these factors should be considered independently andparticular attention should be paid to areas of peripheral interestwhere the exhaustivity and specificity required of the descriptorsare not the same as for the core subject.

In all cases, descriptors should be selected for inclusionin the thesaurus on the basis of their estimated effectiveness forretrieval purposes, and their significance in the material to beindexed.

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1. Methods of avoiding ambiguity in defining descriptors

In the process of maintenance and development of the INISThesaurus, difficulties will be encountered with candidate descriptorswhich have more than one accepted meaning or whose meaning in a givencontext is different to that commonly encountered. Furthermore, itmay also happen that the same concept is written in two or moredifferent ways (synonyms) or the meaning of two candidate descriptorsmay overlap substantially (near-synonyms). In case of synonyms, nearsynonyms (quasi-synonyms) as well as antonyms a certain preferentialdescriptor will be selected always with cross-reference to thenot accepted terms (and vice versa). In such cases the requiredmeaning may be brought out by the use of the following methods:

a) Compound expressions

Although descriptors are preferably self-contained, single termconcepts, the IWIS Thesaurus makes extensive use of modifyingexpressions to define the different meanings associated with a givenconcept, whenever necessary. For the method of entering theresulting compound expression, see J/a below.

e.g. SEPARATED ORBIT CYCLOTRONSor

ABSOLUTE ZERO TEMPERATURE

b) Homonyms

Whenever possible the difficulty arising from homographie terms willbe solved by entering the homonym as a forbidden term withdifferent qualifiers each referring to different descriptors, whichmore clearly identify the different meanings.

In those cases where it is not possible to clearly differen-tiate between different meanings of a homonym by means ofqualifiers, liberal use should be made of scope notes.

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The method preferred by INIS for handling homonyms is the onedescribed under ]/e below. However entering the homonym as aforbidden term with SEE, OR references to better defined descrip-tors is not ruled out.

e.g. preferred display:

-abundance (chemical) USE CHEMICAL COMPOSITION-abundance (isotopic) USE ISOTOPE RATIO-abundance (mineral) USE ORE COMPOSITION

instead of :

-abundance SEE CHEMICAL COMPOSITIONOR ISOTOPE RATIOOR ORE COMPOSITION

c) Synonyms, quasi-synonyms and antonyms

It is rare that two or more candidate descriptors can be consideredas true synonyms. When one candidate descriptor must be searchedevery time that another is searched, they may be treated as synonyms.Descriptors that overlap significantly or represent differentaspects of the same property may be considered quasi-synonyms.Antonyms should be similarly treated. When all the synonyms,quasi-synonyms or antonyms are included in the thesaurus displaythe preferential cross-reference should be used.

The method adopted by INIS is such that the thesaurus willdisplay the preferential term as descriptor. Their synonyms, quasi-synonyms or antonyms will be included as forbidden terms withreference(s) to the descriptors which should be used in theirplace. See also: point d) Forbidden terms, page 20 of theINIS: Manual for Indexing '.

1) IAEA-INIS-12 (INIS: Manual for Indexing)

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e.g. -columbiumUSE NIOBIUM

-maxwell-boltzmann distributionUSE BOLTZMANN STATISTICS

-electric resistivityUSE ELECTRIC CONDUCTIVITY

d) Scope notes

A scope note is a brief explanation which may accompany thedescriptor in the thesaurus display, but does not form part of thedescriptor. It indicates the way in which the descriptor should beused; it need not necessarily consist of a dictionary definition.Scope notes are sometimes used to restrict the usage of a descriptor.(See II/4).

The total length of a scope note in the INI S Thesaurus islimited to a total of 9 (lines) x 28 characters (per line) includingupper and lower case shift characters. In view of its nature ascope note should be as concise and precise as possible. Only in afew exceptional cases a scope note in the INIS Thesaurus exceedsfour to five lines.

e) Qualifiers

It should be explicitly mentioned that in the INIS Thesaurus noqualifiers exist or are allowed as a part of the descriptors.However, they are allowed as a part of forbidden terms of the typementioned under point b) and c) of this chapter. Qualifiers areused extensively to solve the problem of homonym expressions.(See example under III/1/b)

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e.g. -analysis (activation) USE ACTIVATION ANALYSIS-analysis (gas) USE GAS ANALYSIS-analysis (thermal) USE THERMAL ANALYSIS

or-cortex (adrenal) USE ADRENAL GLANDS-cortex (cerebral) USE CEREBRAL CORTEX

Their purpose is to assure an appropriate cross-reference to thepreferential term (descriptor), the introduction of which wasbased on the philosophy of introducing descriptors as "directentries" into the Thesaurus as in the examples above. (See III/3/a)

2. Form of descriptors

a) Word form

Once it has been decided to include a given term in the thesaurus,care should be taken to ensure that the word form used adequatelyconveys the exact meaning intended.

i) Spelling : the most widely accepted spelling of the word shouldbe used. Cases arise, particularly in English, due to varyingusage on different sides of the Atlantic where more than onespelling of a word is accepted, in which case both forms of theword should be included in the thesaurus. In these cases thepreferential cross-reference should be employed. (See HI/3>/c)

e.g. SULFUR OR: LABELED COMPOUNDSSULPHUR LABELLED COMPOUNDS

SULPHUR written with PH could be introduced as a forbiddenterm like: -sulphur USE SULFUR (and vice versa) or provisionscould be made in the programmes for processing descriptors toautomatically correct different spelling of the same concept of

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the type as mentioned above. It may be said that they aretreated like synonyms, if the spellings in common usagediffer very much from each other. (See III/l/c)

ii) Translation: many current technical terms have arisen bytranslation from other languages, but sometimes a modernforeign language or Latin term is incorporated into the spe-cialized vocabulary for a particular subject. When both theforeign language term and its putative translation coexist,they should both be included in the thesaurus and cross-referenced preferentially.

e.g. BRAKING RADIATIONBREMSSTRAHLUNG

Technical terms as mentioned above will for INIS terminologycontrol purposes be treated like synonymous terms. The spellingmost frequently used in the scope of interest, whether theconcept is written in English or in a foreign language, willbe adopted as the preferential term for indexing the conceptin question. (See III/1/e)

The other spelling, whether in English or a translation ofthis concept, could be introduced as a forbidden term with across-reference to the preferential terme.g.

as BREMSSTRAHLUNG is the preferential term in the INISThesaurus, the cross-reference would look as follows:

-braking radiationUSE BREMSSTRAHLUNG

and

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BREMSSTRAHLUNGUP -braking radiation

iii) Transliteration : the problem is further complicated when theforeign language in question is written in a different alphabet.This is particularly true in the case of very specificdescriptors. The transliteration standards to be used forINIS descriptors and forbidden terms are the INIStTrans-literation Rules for Selected Non-Roman Characters . Wherevera choice exists, the transliteration which does not employdiacritical marks should be selected (See III/2/e).

e.g. SPUTNIK SATELLITES

b) Noun form

The descriptor should be in the form of a noun or that part of theverb which is grammatically equivalent. The gerund in English.

c) Number

In general, the plural form should be used for descriptors, parti-cularly when generic terms are involved. The singular and pluralforms of a word denote different concepts, in this case bothshould be entered.

For examples: See table No.l on page 24

1) IAEA-INIS-10 (INIS: Transliteration Rules for SelectedNon-Roman Characters)

T A B L E N O . 1

TYPE OP TERM USE SINGULAR FORM USE PLURAL FORMMaterial terms,such as :chemical compoundsmixturesmaterials

When term is specificas:

UREACELLOPHANEASBESTOS

When term representsa group as :AMINESSOLVENTS

Terms representingproperties, condi-tions, characteristics

When term is specificas:VISCOSITYTEMPERATUREOPACITY

When term representsa group as :

MECHANICAL PROPERTIESTENSILE PROPERTIES

Terms representingequipment, devices,physical objects andelementary particles

Do not use singular Use plural, as:ACCELERATORSWELDSMESONSTEETHSTARS

Special purpose terms Do not use singular Use plural, as :ADHESIVASCATALYSTS

Process terms Use singular, as:CATALYSISFABRICATIONWELDINGMODULATION

Do not use plural

Proper names(A proper name isdefined as the namefor a single uniqueitem)

Use singular, as:FERMI-YANG THEORYPLUTO PLANET

Do not use plural

Disciplines, fields,subject areas

Use singular accor-ding to common usage,as:

MECHANICSHYDRAULICSBIOLOGY

Do not use plural(Words such as"hydraulics" areactually singular)

Cumulative termsrepresenting a groupof: events,occurrencesor effects

Do not use singular Use plural, as:CHEMICAL REACTIONSNUCLEAR EXPLOSIONSELECTRIC DISCHARGES

Specific phenomena,effects or events

Use singular, as:DOPPLER EFFECTALTERNATING CURRENTBOXCAR EVENT

Do not use plural

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d) Abbreviations and acronyms

Abbreviated word forms should be used only when their meaning isinternationally established. Both abbreviated and unabbreviatedforms should be displayed and cross-referenced preferentially.Sometimes the necessity for limiting the length of thedescriptor (see e) below) entails the use of less well establishedabbreviations. A scope note (see III/1/d) could be appended.

e.g. -castillejo-dalitz-dyson polesUSE CDD POLES

and: CDD POLESUP -castillejo-dalitz-dyson poles

i) Reactor abbreviations

Abbreviated reactor names accepted as descriptors for theINIS Thesaurus will always have a reciprocal cross-reference tothe full name of the reactor as forbidden term (and viceversa). This is to guarantee the indexer that the abbrevia-tion in question is not meant to be used for another reactor.If the full name of the reactor displayed as a forbiddenterm would exceed the allowed 30 characters set for thesaurusterms, (see e) below) only the first 30 characters of theforbidden term will be displayed.

e.g. -magnox type gas cooled reactor ^ 'USE MAGNOX TYPE REACTORS

ii) Abbreviation of chemical compound names

Abbreviations of long chemical compound names accepted asdescriptors for the INIS Thesaurus will always have a recip-rocal cross-reference to the not accepted full name of thecompound (and vice versa). For the rest the same explanationas above. A chemical compound name displayed in the INIS

Thesaurus as a forbidden term and exceeding the allowedcharacter set could be:

(tate)e.g. -cyelohexylenedinitrilotetraaceu ^USE CDTA

The cut off name of the chemical compound will still providethe indexer or retriever with sufficient information foridentifying the utilization of the descriptor CDTA. If toomuch of a name is cut off by the JO character limitation,giving rise to possible difficulty in identifying the exactcompound, it may be useful to include that part, which wascut off in a scope note.

The above remarks also apply to acronyms.

e) Character set

The character set for printing the INIS Thesaurus is in upper andlower case letters. INIS descriptors and Narrower Terms (NT's)are printed in upper case whereas Broader Terms (BT's), RelatedTerms (RT's) and forbidden terms are printed in lower case.

The INIS Thesaurus is not only the authority for indexing andquery profiling but also the standard to be used for input processingand query profile compilation. For this purpose and for purposesof thesaurus updating and structure control, it has been stored oncomputer memory devices.

Consequently the limit set on the length of descriptors andforbidden terms is JO characters. Therefore there are exceptionalcases where descriptors or forbidden terms in the INIS Thesaurusare simply cut off after the first JO characters.

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e.g. For a descriptor:

CONTAINMENT RESEARCH INSTALLAT-ZQ

e.g. For a forbidden term:

-cyclopentanediaminetetraacetic

No diacritical marks will be allowed for in INIS descriptorsand forbidden terms. If pertinent they will be transliterated asindicated in: Appendix 1 of the IMIS: Descriptive CataloguingRules '

e.g. mossbauer effectinto MOESSBAUER EFFECT

i) Descriptors

The character set allowed for descriptors is the following:

spaceasterisk *dashRoman alphabet A-ZArabic numerals 0-9

ii) Forbidden terms

The character set allowed for forbidden terms is thefollowing :

1) IAEA-INIS-1 (INIS: Descriptive Cataloguing Rules)

spaceperiodopen parenthesis (plus +asterisk *closed parenthesis )dashslash /comma ,apostrophy 'Roman alphabet A-ZArabic numerals 0-9

iii) Scope notes

The character set for scope notes is the same as for forbiddenterms plus the following special characters:

semicolon ;percent %colon :equal sign =

Furthermore both upper and lower case Roman characters areallowed.

3- Method of entering descriptors in the thesaurus

a) SyntaxCompound expressions consisting of two or more words should belisted preferably by direct entry i.e. not artificially inverted.Inverted entries may be introduced as a forbidden term referringto a direct entry as the descriptor. When a forbidden term isentered in inverted form, the qualifying expression should beenclosed in parentheses.

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e.g. -conductivity (electric)USE ELECTRIC CONDUCTIVITY

and: ELECTRIC CONDUCTIVITYUP -conductivity (electric)

or: -conductivity (thermal)USE THERMAL CONDUCTIVITY

and: THERMAL CONDUCTIVITYUP -conductivity (thermal)

b) Punctuation

Punctuation marks are not allowed in descriptors. (See III/2/e/i),Candidate descriptors exceeding 30 characters are rare, withexception of compound terms. Long compound terms however couldbe abbreviated and the abbreviation used as the preferential term(descriptor) with cross-reference to (limited by ̂ 0 characters)compound term introduced as a forbidden term. (See III/2/d/ii).

c) i) Specialized vocabularies

Certain fields have highly specific systems of nomenclature,or well-established standardized technical vocabularies.Whenever an internationally agreed nomenclature exists, it isused for standardizing INIS Terminology,

e.g. The ISO Nuclear Energy GlossaryThe ISO Standardized TerminologyThe UPAC rules

ii) Specific names

The proliferation of unrelated specific names would tend toconvert the thesaurus into a simple list of identifiers which

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would be self-defeating. It is therefore recommended, thatthe names of unrelated specific entities be avoided as muchas possible.

d) Alphabetization

The method of alphabetization of terms in the INI S Thesaurus isperformed on the basis of computer sort as follows:

spaceperiodopen parenthesis (plus +asterisk *closed parenthesis )dashslash /comma ,apostrophy 'Roman alphabet A-ZArabic numerals 0-9

Note:

The main points of this document have been introduced into theINIS: Manual for Indexing (IAEA-INIS-12 (Rev.l)).