Environmental Markup Language (EML): A Material and Energy Balancing XML Schema Definition

Transcription

1 EnviroInfo 2008 (Lüneburg) Environmental Informatics and Industrial Ecology Environmental Markup Language (EML): A Material and Energy Balancing XML Schema Definition Hans-Knud Arndt, Henner Graubitz and Andreas Dammert 1 Abstract For a systematic evaluation of an organizations environmental performance methods for data pooling are needed so that data about services, or the production of goods can be collected and the evaluation of the associated environment is possible. This information gain is the base for improvements of the environmental performance and supports the top management in its strategic planning. One useful method can be seen in a material and energy balancing which enables organizations to operationalize environmental protection. Due to the often heterogeneous information and communication technologies (ICT) systems in organizations a general practical exchange format for the representation and processing of material and energy information is required. Therefore this publication describes the development of an XML schema definition for material and energy balancing. The development of this XML schema definition is based on the DIN EN ISO 14040:2006 standard according to Life Cycle Assessment (LCA) and includes the linkage between ecologic and economic information. Keywords Environmental Markup Language (EML), extensible Markup Language (XML), XML Schema Definition (XSD), Material and Energy Balancing 1. Material and Energy Balancing A step-by-step collection of environmental aspects in corporate transactions (Arndt 1997, 169) can be described as life cycle analysis. In contrast life cycle analysis is described by the DIN EN ISO 14040:2006, published in Germany by the German Institute for Standardization (Deutsches Institut für Normung e.v.; DIN) as compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle. The life cycle consecutive and interlinked stages of a product system, from raw material acquisition or generation from natural resources to final disposal (DIN ISO 2006a, 7). A possible barrier between the idea of a life cycle analysis and the concept of a material and energy balancing can been seen in the fact that life cycle analysis affects the (external) product balancing. Compared to that the material and energy balancing represents flow calculations and concentrates onto the production of goods, services, and refers onto a time period (Arndt 1997, 170). Both methods have the comparison of input and output flows for a product, a product service, or a product system in common. This is also called life cycle inventory analysis (DIN EN ISO 2006b, 8). The material and energy balancing consists of four phases (DIN EN ISO 2006a, 4): 1 Otto-von-Guericke-Universität Magdeburg, Institut für Technische und Betriebliche Informationssysteme, AG Managementinformationssysteme, Universitätsplatz 2, D Magdeburg, Germany, hans-knud.arndt@iti.cs.uni-magdeburg.de, web: 54

2 1. The goal and scope definition (intended application, the reasons for carrying out the study, intended audience, for example to whom the results may concern) 2. Inventory analysis (data collection and calculation procedures to quantify relevant inputs and outputs of a product system) 3. Impact assessment (associating inventory data with specific environmental impact categories and category indicators, thereby attempting to understand these impacts) 4. Interpretation (understandable, complete and consistent presentation of the results, in accordance with the goal and scope definition of the study) 2. Related Work In recent years research has been done to provide exchange formats specially for life cycle inventory analysis (LCI). E.g. since 1992 the Society for Promotion of Life-Cycle Analysis Development (SPOLD) supports the development of life cycle analysis. Beside publications the SPOLD developed a data format which offers the possibility to exchange life cycle analysis data electronically. This format, also known as SPOLD-format, follows the goal to expand environmental understanding and the possibility to exchange and compare ecological data, independent in which format the data has been saved before. In 2001 all SPOLD activities have been stopped (Weidema 2003). The SPOLD-format consists of different datasets where each dataset is build by one text file and each dataset contains information. Each row of one text file represents a field in the dataset and consists of an area- or field ID, a field counter, and the actual content. All these elements will be separated by a tabulator. The notation of each field and area is fixed by a SPOLD specification. Depending on the affiliation the field areas allows the possibility to group elements to special subjects. For example the SPOLD format offers the possibility to save information about the dataset, its temporal logs, and user information. The format and the length of each field is pre-given by the SPOLD specification, where SPOLD differs between text, different number types (float, decimal, integer), or dates. Via identification numbers different fields can be referred. One of the current formats which uses the extensible Markup Language (XML) to exchange environmental data can be seen in the Publicly Available Specification (PAS), also known as PAS 1025:2003. PAS defines an XML schema definition (XSD) which defines interfaces between an Enterprise-Resource- Planning- (ERP) and an environmental information system (EIS) to enable data exchange. Usually ERPsystems reflect all business process of one company. That s why these systems represent excellent data sources for an environmental management. Additionally with the help of PAS it is possible to connect ERP data with an EIS to evaluate it. The PAS 1025:2003 defines that all data will be stored in projects, and separated into master data and transaction data. The usage of master data means that data will be used over a long time period without changing so often. Instead the lifetime of transaction data is limited and each state of its life cycle can be described. This data applies to fixed points in time which is necessary to understand its information. Material master data (materials) and other information are bundled in projects (project) (see Figure 1). To structure this data it has been referred to material groups (materialgroups), and cost type groups (costtypegroups). Additionally currency units and its exchange rate can be add. Different information about the inventory at the beginning and the end of a project period can be done in the element stocks. Instead the element resourcelists reflects all details about master data where the allocation of each resource depends onto its work process. Each list of resources orders its procedures with corresponding work processes and applies costs. 55

3 Fig. 1: Partition of projects in PAS 1025:2003 (DIN 2003, 7) One of the critics about the SPOLD format - by and the fact that this format will not be developed anymore - can be seen in the problem that this format is not flexible enough to save environmental data. The data format with the specification PAS 1025:2003 can be seen as a data format which enables the possibility to exchange environmental related data in the area of enterprise resource planning (ERP)- systems. It concentrates onto the integration of master data, and all its corresponding resources and working processes. To enable environmental management analysis these data must be completed with comparable environmental data. This makes the format PAS 1025:2003 unhandy as an exchange format for the energy and material balance mentioned in DIN EN ISO 14040:2006. But it can be still used as data basis which is required for building a material and energy balance. These facts reflects the desire for a flexible format which can be used to build up a material and energy balance without the given restrictions of the SPOLD-format and can be extended over the possibilities of the PAS 1025: Developing a Material and Energy Balancing XML-Schema Definition 3.1 Procedure model The goal of this chapter can be seen in the formulation of a general valid XML schema definition. A model will be created which is based and satisfies all fundamentals demands of the DIN EN ISO 14040:2006 and 14044:2006 so that these format can be used to build up a material and energy balance. Nonetheless an integration of an ecological standard form of accounts should be possible where quantity and value flows can be used. The advantage by choosing XML as modeling language, and XML-schema for the definition of the document type can be seen in two points: first the integration of data coming from different application systems will be enabled (e.g. listing of material and energy balancing and a corresponding integration of monetary values), and second - by a restriction of data types, or conditions for primary or foreign keys - a valid format can be guaranteed. 56

4 For the creation of a material and energy XML schema definition a modified procedure model based on (Schraml 1997, ) can be used. Schraml (1997) uses the classical phase model of software engineering to build up his procedure model:! Phase 1: Target Definition: Generally the first phase of a procedure model can be seen in the analysis of general project facts when creating a document type definition. Most important is the target definition. There should be a clear description which document classes must be created and to which demand they correspond.! Phase 2: Analysis of the main determinants: While creating a document type definition the subject of the second phase should include the analysis of all parameters which influence our document type model. There must be a distinction between general condition on the one hand, and demands which has been caused by tasks of users on the other hand. General conditions in this context means to use factors which are not related to document instances, or user profiles. These factors should be more abstract, or accord to regulations. For example this could be legal rules, internal agreements in organizations, or guidelines for standardization of documents for document classes when deriving special standard regulations. Step by step these general conditions will be analyzed depending on the content, meaning, or structure it concerns to. Gradually this analyze will be continued while regarding all other demands. It results in an ordered tabular form of a so called potential semantic component. These semantic components reflects content components which can be uses for special information aims on the one hand, or can be used for structuring document instances. First it will be stored separately to receive an overview about all different influences.! Phase 3: Selection of relevant semantic components: This phase includes the selection of relevant semantic components. It enables the possibility to make a decision which potential semantic components should enter the model. While all potential semantic components has been collected separately before the components will be fuzzy structured by using its content connections. For later modeling clear declarations will be established. The so developed list of relevant potential components will be used as the modeling base of the document type definition.! Phase 4: Model design: The last phase will be used to determine associations between the relevant semantic components internally and to the general schema definition externally. Using the topdown design onto a documents general structure in an iterative process it is possible to receive a high granularity structure containing a high detail degree. The quality of the model will be improved while testing example documents onto the function of the XML-schema. This procedure model guarantees an ordered, step by step procedure when creating a document type definition. That s why the principle of modeling will be used as guidelines for the creation of phases of the document type definition and specially the modeling phase. 3.2 Schema design In the first step of the modeling the raw structure of the relevant semantic components has been transferred into a XML schema definition (figure 2). The root element materialandenergybalance represents the completeness of the material and energy balance. It is divided into information about the document (emlmetarecord), the definition about the target of the study (goaldefinition), the definition about the evaluation and its corresponding barriers (scopedefinition), the life cycle inventory analysis (inventoryanalysis), the impact assessment (impactassessment), and the analysis (interpretation). The main parts of the material and energy balance are modeled as sequence whereby the iterative process which is used in the modeling phase will be reflected. 57

5 Fig. 2: Raw structure of the XML schema definition The element emlmetarecord contains the entire kernel components of the EML (Arndt et al. 2001, ) which has been transferred to a XML schema definition. In figure 3 the raw structure of the XML schema of an EML is represented. It contains elements for the following points:! Dataset information (recordinformation),! Data source information (resourceinformation),! Indexing information (indexinformation),! Information about the usage area (scope),! Information about the time reference (temporal),! Information about the responsible person behind (responsibilities). Fig. 3: Content model about the EML root element 58

6 A semantic representation of the element life cycle inventory analysis is displayed in figure 4. The element ecoaccountsystem enables all material and energy flows to be classified into the ecological standard form for accounts. The element unitprocessassignment represents a lists of all possible process modules while the units which has been used by the data collection will be stored in usedunits. Additional information about the data collection, or data calculation will be mentioned in the element documentation. Fig. 4: Elements of the life cycle inventory analysis The idea for a classification of material and energy flows into the ecological standard form of accounts has been taken from PAS Like the idea how this standard refers material or type of costs the type ecoaccountsystemtype has been taken. It contains multiple accountsystem elements (compare figure 5). Each element reflects an ecological standard form of accounts and can be identified by a unique id. Fig. 5: Classification for the ecological standard form of accounts A hierarchical order and classification will be realized by the attribute parentid. That s why each ecological standard form of accounts can be divided into environmental types, or types of cost. If one of these types contains more than one parent part a group can be build up. An element without a parental ecological standard form of accounts will be self-referred by its own identification key. 59

7 If there is a demand for a specified display order of the ecological standard form of accounts the attribute weight can be added. It contains a numerical value which provides the possibility to sort in the group internally. An ascending order is possible whereas the value 1 reflects the highest priority and would display this element as number one in the group. The reliable parts of the impact assessment (DIN EN ISO 2006b, 33) are:! impact categories,! impact category indicators,! characterization models. Impact categories represent environmental topics (e.g. climate change) to which results of the life cycle inventory analysis can be referred. To estimate the different effects of material onto impact categories compared to the quantity the quantity should be given with characterization factors. Using this characterization factor means the quantity will be recalculated into same unit so that a comparison is possible (e.g. kg CO 2 equivalent). A characterization model reflects the environmental impact mechanism through an association description of a life cycle inventory analysis result to its corresponding impact indicator (DIN EN ISO 2006b, 35). For a decision of all influences onto the impact category all to common units recalculated results of the life cycle inventory analyses must be sum up and represented as impact indicator result. Figure 6 shows the main parts of the modeled impact assessment. As it can be seen a general division between the listing of impact categories (impactcategoryinventory) and the optional elements (optionalelements) take part. Fig. 6: Phase of the impact assessment 4. Outlook In the next step a validation of the created XML-schema should be done. With this step different model improvements are possible. E.g. it is thinkable that a collection of the characterizing factors which has been used in the phase of the impact assessment can be created. Like the listing of used units in the life cycle inventory analysis this collection can be used to avoid errors which can be made while creating the material and energy balance. On the other hand there exists the possibility to store different information about currency units (compared to PAS 1025:2003) for a later realization. Additionally all user requirements should influence the XML-schema so that the acceptance rate for XML-schema usage raises. References Arndt, H.-K. (1997): Betriebliche Umweltinformationssysteme - Gestaltung und Implementierung eines BUIS-Kernsystems. Wiesbaden. Arndt, H.-K.; Freitag, U.; Kazakos, W.; Schwartz-Glaesker, S.; Westbomke, J. (2001): Erster Entwurf einer Dokumenttyp-Definition für die Kernelemente umweltbezogener Metadaten einer Environ- 60

8 mental Markup Language (EML). In: Tochtermann, K.; Riekert, W.-F.: Neue Methoden für das Wissensmanagement im Umweltschutz. 4. Workshop des GI-Arbeitskreises Hypermedia im Umweltschutz und Workshop 3 der GI-Initiative Environmental Markup Language, Marburg, S DIN Deutsches Institut für Normung e. V. (Hrsg.). (2003): PAS 1025: Austausch umweltrelevanter Daten zwischen ERP-Systemen und betrieblichen Umweltinformationssystemen. Berlin/Wen/Zürich. DIN Deutsches Institut für Normung e. V. (Hrsg.). (2006a): DIN EN ISO 14040:2006 Umweltmanagement, Ökobilanz, Grundsätze und Rahmenbedingungen. Berlin/Wien/Zürich. DIN Deutsches Institut für Normung e. V. (Hrsg.). (2006b): DIN EN ISO 14044:2006 Umweltmanagement, Ökobilanz, Anforderungen und Anleitungen. Berlin/Wien/Zürich. Schraml, T. (1997): Operationalisierung der ökologiebezogenen Berichterstattung aus Sicht des Informationsmanagements. Konzeption eines Vorgehensmodells zur formalisierten Explikation logischer Dokumenttypmodelle im Rahmen der Umweltkommunikation von Unternehmen. Dissertation, Technische Universität Dresden. Weidema, B. (2003): 2.-0 LCA consultants. 61