The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform

Michael M. Konstantinov - One of the best experts on this subject based on the ideXlab platform.

  • Computer Expert System for Epithermal Gold-Silver Deposit Prognostication (Okhotsk–Chuckchee Volcanic Belt, Northeast Russia)
    Natural Resources Research, 1999
    Co-Authors: Sergey F. Strujkov, Irina A. Chizhova, Michael M. Konstantinov
    Abstract:

    The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an Expert system (“solution tree”) was compiled. The Computer system is intended to be an assistance to an Expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an Expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the Expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal Computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.

  • Computer Expert system for epithermal gold silver deposit prognostication okhotsk chuckchee volcanic belt northeast russia
    1999
    Co-Authors: Sergey F. Strujkov, Irina A. Chizhova, Michael M. Konstantinov
    Abstract:

    The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an Expert system (“solution tree”) was compiled. The Computer system is intended to be an assistance to an Expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an Expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the Expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal Computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.

Sergey F. Strujkov - One of the best experts on this subject based on the ideXlab platform.

  • Computer Expert System for Epithermal Gold-Silver Deposit Prognostication (Okhotsk–Chuckchee Volcanic Belt, Northeast Russia)
    Natural Resources Research, 1999
    Co-Authors: Sergey F. Strujkov, Irina A. Chizhova, Michael M. Konstantinov
    Abstract:

    The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an Expert system (“solution tree”) was compiled. The Computer system is intended to be an assistance to an Expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an Expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the Expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal Computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.

  • Computer Expert system for epithermal gold silver deposit prognostication okhotsk chuckchee volcanic belt northeast russia
    1999
    Co-Authors: Sergey F. Strujkov, Irina A. Chizhova, Michael M. Konstantinov
    Abstract:

    The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an Expert system (“solution tree”) was compiled. The Computer system is intended to be an assistance to an Expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an Expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the Expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal Computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.

Irina A. Chizhova - One of the best experts on this subject based on the ideXlab platform.

  • Computer Expert System for Epithermal Gold-Silver Deposit Prognostication (Okhotsk–Chuckchee Volcanic Belt, Northeast Russia)
    Natural Resources Research, 1999
    Co-Authors: Sergey F. Strujkov, Irina A. Chizhova, Michael M. Konstantinov
    Abstract:

    The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an Expert system (“solution tree”) was compiled. The Computer system is intended to be an assistance to an Expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an Expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the Expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal Computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.

  • Computer Expert system for epithermal gold silver deposit prognostication okhotsk chuckchee volcanic belt northeast russia
    1999
    Co-Authors: Sergey F. Strujkov, Irina A. Chizhova, Michael M. Konstantinov
    Abstract:

    The Okhotsk–Chuckchee volcanic belt (OCVB) represents a world class gold–silver province, being a well-studied part of the Circum-Pacific Rim. Extensive research, preceding the system compilation, included collection of various data on major gold–silver, silver–lead–zinc, and tin–silver ore fields (with some data on minor gold–quartz, gold–sulfide, and gold–rare-metal sites). The database consists of 129 ore fields of the OCVB and comprises 433 geological, mineralogical, geochemical, and geophysical indicators. Using the original pattern recognition programs (accounting the frequencies and correlation of the indicators), the most informative indicators were selected, their weights (both positive and negative) were identified, and an Expert system (“solution tree”) was compiled. The Computer system is intended to be an assistance to an Expert in the ore field potential evaluation. The system includes several blocks of questions with a goal of classifying the geochemical type and size of the analyzed ore field. The questions have an indirect character, so they could be answered by an Expert at early stages of exploration (before drilling). The level of recognition of sizes of the ore sites in the control populations is 95% or higher. The aim of the Expert system is to reestimate a large number of known ore sites in a relatively brief period of time with the aid of the personal Computer. The revealed patterns could be used in other less studied parts of the Circum-Pacific belt.

Lubomír Tichý - One of the best experts on this subject based on the ideXlab platform.

  • National vegetation classification of the Czech Republic: a summary of the approach
    Phytopathology, 2018
    Co-Authors: Milan Chytrý, Lubomír Tichý
    Abstract:

    Aim: To describe the classification approach and protocols that were used in the project Vegetation of the Czech Republic and relate them to the comparative framework for broad-scale plot-based vegetation classification proposed by De Caceres et al. (2015). This description should facilitate comparison of this national vegetation classification with vegetation classifications in other countries. - Location: Czech Republic. - Methods: The project Vegetation of the Czech Republic, realized from 1997 to 2013, was based on the analyses of vegetation-plot records from the Czech National Phytosociological Database. Associations were defined as the basic hierarchical level using formal definitions created with the Cocktail method. These formal definitions were included in a Computer Expert system for automatic identification of associations. Evaluation and characterization of associations were based on the groups of plot records assigned to the particular associations by the Expert system. Higher classification levels were classified by type-based grouping of associations. A novel statistical method for determining diagnostic species of vegetation types was developed within the project. All the analytical procedures used and developed for the project were included in the JUICE program. - Results: The national vegetation classification system was published in a four-volume monograph from 2007 to 2013. It consists of five hierarchical levels with nested vegetation types, including 9 formations, 39 classes, 138 alliances, 496 associations and for some associations also variants. At the same time the project infrastructure, including the Expert system and the JUICE program, was published online. - Conclusions: The national vegetation classification of the Czech Republic provided novel classification approach and protocols. Several elements of these protocols have been subsequently applied in other countries. At the national level, the classification has found various applications both in nature conservation and in basic research.

  • formalized classification of species poor vegetation a proposal of a consistent protocol for aquatic vegetation
    Journal of Vegetation Science, 2015
    Co-Authors: Flavia Landucci, Lubomír Tichý, Kateřina Sumberova, Milan Chytrý
    Abstract:

    Aims: Most vegetation classification systems developed for large areas include various inconsistencies. Therefore, we (1) propose a new consistent Cocktail-based approach to redefine the traditional phytosociological classification of species-poor vegetation; (2) apply it to create a classification protocol for aquatic vegetation; (3) implement this protocol in a Computer Expert system; and (4) test it with a data set previously classified using an older version of the Cocktail method. Methods: The new approach uses formal logic to provide formal definitions of vegetation units. In the classification protocol for aquatic vegetation we defined consistent criteria for delimitation of associations according to the concepts that are predominantly used in phytosociology, based on species cover, dominance patterns and functional species groups. We applied these criteria in a Computer Expert system running in the JUICE 7.0 program, and applied them to a test data set of 12171 vegetation plots from the Czech Republic containing at least one aquatic species. The new classification was compared with (1) the previous national Cocktail classification based on species cover values and in few cases on sociological species groups, and (2) a non-formalized Expert-based classification. Results: Thirteen functional species groups were created to build logical formulas of 64 aquatic associations and 5297 (44% of the total data set) vegetation plots were assigned to these associations, i.e. by 4% and 12% more than in the previous Cocktail and Expert-based classifications, respectively. There was 94% and 83% classification agreement with the previous Cocktail and Expert-based classification. Conclusions: The new approach produces a formal, consistent and unequivocal classification of species-poor vegetation with several advantages over similar approaches. It provides not only a set of formal definitions of vegetation units, but also a set of rules for building such definitions. All associations with common characteristics are defined by structurally identical formulas, ensuring consistency of the classification. While similar approaches for species-rich vegetation use sociological species groups, which are not applicable to species-poor vegetation, the new approach introduces the use of functional species groups, which reflect vegetation physiognomy and spatial structure and, in combination with species dominance, enable the classification of species-poor vegetation in a similar manner as in traditional phytosociology.

  • formalized reproduction of an Expert based phytosociological classification a case study of subalpine tall forb vegetation
    Journal of Vegetation Science, 2003
    Co-Authors: Martin Koci, Milan Chytrý, Lubomír Tichý
    Abstract:

    Delimitation of vegetation units in phytosociology is traditionally based on Expert knowledge. Applications of Expert-based classifications are often inconsistent because cri- teria for assigning releves to vegetation units are seldom given explicitly. Still, there is, e.g. in nature conservation, an increas- ing need for a consistent application of vegetation classification using Computer Expert systems for unit identification. We propose a procedure for formalized reproduction of an Expert-based vegetation classification, which is applicable to large phytosociological data sets. This procedure combines Bruelheide's Cocktail method with a similarity-based assign- ment of releves to constancy columns of a vegetation table. As a test of this method we attempt to reproduce the Expert-based phytosociological classification of subalpine tall-forb vegeta- tion of the Czech Republic which has been made by combina- tion of Expert judgement and stepwise numerical classification of 718 releves by TWINSPAN. Applying the Cocktail method to a geographically stratified data set of 21 794 releves of all Czech vegetation types, we defined groups of species with the statistical tendency of joint occurrences in vegetation. Combi- nations of 12 of these species groups by logical operators AND, OR and AND NOT yielded formal definitions of 14 of 16 associations which had been accepted in the Expert-based classification. Application of these formal definitions to the original data set of 718 releves resulted in an assignment of 376 releves to the associations. This assignment agreed well with the original Expert-based classification. Releves that remained un- assigned because they had not met the requirements of any of the formal definitions, were subsequently assigned to the asso- ciations by calculating similarity to releve groups that had already been assigned to the associations. A new index, based on frequency and fidelity, was proposed for calculating similar- ity. The agreement with the Expert-based classification achieved by the formal definitions was still improved after applying the similarity-based assignment. Results indicate that the Expert- based classification can be successfully formalized and con- verted into a Computer Expert system.

Milan Chytrý - One of the best experts on this subject based on the ideXlab platform.

  • National vegetation classification of the Czech Republic: a summary of the approach
    Phytopathology, 2018
    Co-Authors: Milan Chytrý, Lubomír Tichý
    Abstract:

    Aim: To describe the classification approach and protocols that were used in the project Vegetation of the Czech Republic and relate them to the comparative framework for broad-scale plot-based vegetation classification proposed by De Caceres et al. (2015). This description should facilitate comparison of this national vegetation classification with vegetation classifications in other countries. - Location: Czech Republic. - Methods: The project Vegetation of the Czech Republic, realized from 1997 to 2013, was based on the analyses of vegetation-plot records from the Czech National Phytosociological Database. Associations were defined as the basic hierarchical level using formal definitions created with the Cocktail method. These formal definitions were included in a Computer Expert system for automatic identification of associations. Evaluation and characterization of associations were based on the groups of plot records assigned to the particular associations by the Expert system. Higher classification levels were classified by type-based grouping of associations. A novel statistical method for determining diagnostic species of vegetation types was developed within the project. All the analytical procedures used and developed for the project were included in the JUICE program. - Results: The national vegetation classification system was published in a four-volume monograph from 2007 to 2013. It consists of five hierarchical levels with nested vegetation types, including 9 formations, 39 classes, 138 alliances, 496 associations and for some associations also variants. At the same time the project infrastructure, including the Expert system and the JUICE program, was published online. - Conclusions: The national vegetation classification of the Czech Republic provided novel classification approach and protocols. Several elements of these protocols have been subsequently applied in other countries. At the national level, the classification has found various applications both in nature conservation and in basic research.

  • formalized classification of species poor vegetation a proposal of a consistent protocol for aquatic vegetation
    Journal of Vegetation Science, 2015
    Co-Authors: Flavia Landucci, Lubomír Tichý, Kateřina Sumberova, Milan Chytrý
    Abstract:

    Aims: Most vegetation classification systems developed for large areas include various inconsistencies. Therefore, we (1) propose a new consistent Cocktail-based approach to redefine the traditional phytosociological classification of species-poor vegetation; (2) apply it to create a classification protocol for aquatic vegetation; (3) implement this protocol in a Computer Expert system; and (4) test it with a data set previously classified using an older version of the Cocktail method. Methods: The new approach uses formal logic to provide formal definitions of vegetation units. In the classification protocol for aquatic vegetation we defined consistent criteria for delimitation of associations according to the concepts that are predominantly used in phytosociology, based on species cover, dominance patterns and functional species groups. We applied these criteria in a Computer Expert system running in the JUICE 7.0 program, and applied them to a test data set of 12171 vegetation plots from the Czech Republic containing at least one aquatic species. The new classification was compared with (1) the previous national Cocktail classification based on species cover values and in few cases on sociological species groups, and (2) a non-formalized Expert-based classification. Results: Thirteen functional species groups were created to build logical formulas of 64 aquatic associations and 5297 (44% of the total data set) vegetation plots were assigned to these associations, i.e. by 4% and 12% more than in the previous Cocktail and Expert-based classifications, respectively. There was 94% and 83% classification agreement with the previous Cocktail and Expert-based classification. Conclusions: The new approach produces a formal, consistent and unequivocal classification of species-poor vegetation with several advantages over similar approaches. It provides not only a set of formal definitions of vegetation units, but also a set of rules for building such definitions. All associations with common characteristics are defined by structurally identical formulas, ensuring consistency of the classification. While similar approaches for species-rich vegetation use sociological species groups, which are not applicable to species-poor vegetation, the new approach introduces the use of functional species groups, which reflect vegetation physiognomy and spatial structure and, in combination with species dominance, enable the classification of species-poor vegetation in a similar manner as in traditional phytosociology.

  • formalized reproduction of an Expert based phytosociological classification a case study of subalpine tall forb vegetation
    Journal of Vegetation Science, 2003
    Co-Authors: Martin Koci, Milan Chytrý, Lubomír Tichý
    Abstract:

    Delimitation of vegetation units in phytosociology is traditionally based on Expert knowledge. Applications of Expert-based classifications are often inconsistent because cri- teria for assigning releves to vegetation units are seldom given explicitly. Still, there is, e.g. in nature conservation, an increas- ing need for a consistent application of vegetation classification using Computer Expert systems for unit identification. We propose a procedure for formalized reproduction of an Expert-based vegetation classification, which is applicable to large phytosociological data sets. This procedure combines Bruelheide's Cocktail method with a similarity-based assign- ment of releves to constancy columns of a vegetation table. As a test of this method we attempt to reproduce the Expert-based phytosociological classification of subalpine tall-forb vegeta- tion of the Czech Republic which has been made by combina- tion of Expert judgement and stepwise numerical classification of 718 releves by TWINSPAN. Applying the Cocktail method to a geographically stratified data set of 21 794 releves of all Czech vegetation types, we defined groups of species with the statistical tendency of joint occurrences in vegetation. Combi- nations of 12 of these species groups by logical operators AND, OR and AND NOT yielded formal definitions of 14 of 16 associations which had been accepted in the Expert-based classification. Application of these formal definitions to the original data set of 718 releves resulted in an assignment of 376 releves to the associations. This assignment agreed well with the original Expert-based classification. Releves that remained un- assigned because they had not met the requirements of any of the formal definitions, were subsequently assigned to the asso- ciations by calculating similarity to releve groups that had already been assigned to the associations. A new index, based on frequency and fidelity, was proposed for calculating similar- ity. The agreement with the Expert-based classification achieved by the formal definitions was still improved after applying the similarity-based assignment. Results indicate that the Expert- based classification can be successfully formalized and con- verted into a Computer Expert system.