Use-Case Driven Domain Analysis for Milk Production Information Systems

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1 Use-Case Driven Domain Analysis for Milk Production Information Systems Andrea Carla Alves Borim a, Antônio Mauro Saraiva b and Carlos Alberto Ramos Pinto c a Faculdade Comunitária de Campinas Anhanguera Educacional, Brazil, andrea.borim@unianhanguera.edu.br b Escola Politécnica, Universidade de São Paulo, Agricultural Automation Laboratory, Brazil, amsaraiv@usp.br c Faculdades COC, Brazil, carp@coc.com.br Abstract The dairy production process is complex and involves many aspects and activities. In order to make good management decisions the farmer must manipulate a lot of data. Information technology tools have been used by dairy farmers for a long time but they have become even more important as the market competition and demand for quality increased. Many software applications are available to support dairy farms management. However, most of them cover only a few aspects of the dairy production while it would be desirable to have more comprehensive systems. Due to their proprietary nature information exchange between different software packages is hindered or literally impossible. Component-based software development can help overcame many of the interoperability and scalability problems encountered nowadays. In order to help build a sound foundation for the development of such components it is necessary to go through a detailed analysis of the problem. This paper presents a domain analysis based on the concept of use-cases applied to the dairy production domain. The concept of usecase was adopted because it allowed a clear understanding of the functions that the system should provide from its users point of view. The model includes class diagrams which can be analyzed and understood by the users, since it is based on real-world objects. The model obtained will be used for the development of a component repository for animal production information systems. Key words: dairy production, information systems, modelling, object oriented modelling, domain analysis 1 Introduction Dairy production in Brazil has been changing strongly since 1990 as the government interference in the market ended. Since then a lot of work has been done by the farmers to overcome the problems caused by the end of price determination, by the competition of imported (and subsidized) products, by the high prices of inputs and raw material and by changes in the national economy. Considering this scenario the main goal of dairy producers is to minimize the cost and maximize the production optimizing the profits. Dairy production demands the management of many variables for its success. This is especially true for high technology production systems that must be very competitive and deal with up to date market information. Many information systems have been developed as management tools for use in milk production farms and can be found both in the market and on research centers. However those systems usually deal only with some aspects of the problem such as nutrition, reproduction and milk production. Although some of those systems are clearly more comprehensive than others they fail on some other points, for instance on not allowing a seamless integration with other information systems, other data sources, with field equipment, etc. An important part of the problem is the monolithic and proprietary character of that software. Component-based software development is a trend and an attempt to manage the ever increasing complexity of software systems and their demand for evolution, integration and data-sharing. In order to 1303

2 support this approach, a software architecture must be designed defining an application in terms of components and their interaction. As part of an on-going initiative towards the development of agricultural software components a domain modelling activity was conducted. It is the basis for the development of information systems that can be more flexible and interoperable. That domain analysis was based on use-cases, adopting the Unified Modelling Language, UML, and its main diagrams for software analysis. 2 Domain Analysis and Model Development A model can be seen as an abstraction of the real world, which is developed with a specific objective such as to provide a better understanding of a problem or a domain. The model is built omitting irrelevant details of the real subject, and because of that, it is easier to deal with. (Rumbaugh et al., 1997) The main goal is to develop an object-oriented model for information systems related to dairy production. This model will be the base for future software implementation. Considering this goal, an abstract model was developed, independent of implementation choices and technologies. It is a meta-model which describes the main characteristics of a class of systems designed for dairy production facilities. The method outline was based in the goals (Saraiva, 1999): cover only the pre-analysis and analysis phases of a system development life cycle; define a structure which is robust to changes the domain may undergo; incorporate a deep study of the problem domain; apply well-known concepts and notations that facilitate the understanding of the model; Considering these goals, the object oriented paradigm was chosen due to its characteristics and UML Unified Modelling Language, was used to represent the model. The model development consisted in two phases: System Requirement Definition, and Analysis (Borim, 2003). 2.1 System Requirement Definition In order to describe the requirements for that class of systems the first step was a deep research of the problem domain by means of literature review, of other software analysis, and of interviews and visits to dairy production companies. Based on this research, a text describing the problem, named Problem Enunciation, was created. This text contains the main characteristics of the real problem and at this point there is no concern about being precise: the textual description is naturally ambiguous in some aspects. The main characteristics encountered for the systems are: They should guide the manager s or the owner s decisions related to the dairy production. Therefore information about the place, the cattle, the financial conditions and the manipulation techniques should feed the system. Considering this information, the system should provide guidelines, reports, analysis and efficiency of the dairy production. They should be able of receiving data form electronic devices installed in the dairy system and manual input as well. Also, the system should generate data for automatic control equipments that act in the cattle manipulation. The systems are designed to be useful for small dairy producers, due the facility of manual information input. The system should provide communication between different systems and XML would be a very useful standard to be applied. The systems should allow the configuration of intercommunication patterns, to provide inputs from different sources and systems. 1304

3 It is high recommendable that the system keep data for each cow in the dairy system, to provide detailed reports that would be impossible considering samples. The systems should generate graphics and reports to provide a easy interpretation of the dairy productions status and efficiency. They should be configured by the system operator. Considering the information of production, body constitution, feed requirements, gender and weather, the system should recommend an amount of food to optimize the dairy production, minimizing the production costs. The systems should simulate situations based in the stored data, providing estimations of costs and production. Different scenarios should be configured providing estimations off hypothetic production and cost conditions. The system should be developed considering the man-machine interface theory to improve its usability. A help facility should be available to guide the system operation. The system should provide information and knowledge about dairy production that helps in the tasks and as a decision guide. For instance, information about food requirements are used in estimation of food that should be provide for the cattle in the way of optimize the production. Information about equipment and background products should be stored in the system. This database should be provided by the system administrator as part of system configuration. All files created by the system should be named following the proceeds of software engineering. A log file should be created to register all important happenings in the dairy production. The system should be developed considering open source requirements, applying standards of development systems for software integration, providing communication between different hardware and software systems. Based on this text, the description of a Use Case Model was then derived. This model presents diagrams and textual descriptions of the use cases, which are the ways the actors (users) interact with the system. It helps define the limits of the system within the environment. Fig.1 Use case model 1305

4 The use case model derived was the one presented in Figure 1. It shows that the main functions of the system are insert field data, generate reports, generate output files and configure the system. It also shows the five actors that represent the classes of users of the system: operator, manager, dataacquisition equipment, printers and actuator equipment. At this point the model is deliberately simple but as the use cases are detailed the complexity of the interaction user-system is revealed. This diagram hides a complex set of sub-use-case and was simplified on purpose. The next step was then describing these use cases in great detail in order to allow for the identification of the objects for a model of the domain. The list of sub-use-cases that were grouped in the four main use cases is presented below. For each of them a detailed description of the interactions between system and user was written. Configure the system: Configure the system New operator register Cadastre inputs used on the farm Cadastre food used Cadastre equipments Cadastre field areas Cadastre income items and codes Cadastre expense items and codes Cadastre investment items and codes Cadastre cattle management rules Create system shortcuts Cadastre information for use guide Insert field data: Cadastre farm s data Cadastre farmer s data Cadastre animal s data Input livestock production indices Input reproduction data Input production data Input sanitary control data Input health and disease diagnose data Input food data Input incomes Input expenses Input investments Input animal death data Input food suggestion Input suggestion for animal rejection Input diseases and sanitary control suggestion Input data from data acquisition equipment Input field condition data Input milk price data Generate reports: Generate financial report Generate productivity report Generate production and reproduction indices report Generate report about a particular animal Generate other reports Generate simulations Generate output files: Generate files for control equipments 1306

5 Each description of the sub-use-cases, text or graphical, adds more structure to the knowledge of the domain as the analysis proceeds. The final level adopted for this work was that of deriving object models for the domain. The objects were selected from the use cases descriptions. 2.2 Analysis Phase In the Analysis phase the class diagrams for each use case were developed. Instead of having a single object diagram for the whole domain, for the sake of legibility of the diagrams, the choice was to keep separate object diagrams for each use case. The objects that appear in more than one diagram show the links that exist between them. Fig. 2 presents the class diagram for the use case generate output file. This use case describes actions related to file creation and communication with devices. The other diagrams are not shown here for the sake of brevity. Fig. 3 presents a subsystem diagram for the dairy production system. This diagram allows a better comprehension of the system. Another reason of the development of this diagram is guide the modular implementation and further integration. 3 Conclusion Due to the dairy production domain complexity the information systems it demands are identically complex and their development can benefit from the use of techniques that allow a broader understanding of the domain prior to detailing and implementing specific systems. In order to help understand the complexity of dairy production and to provide guidelines for specific systems development, a domain analysis was conducted using techniques and notations from object orientation and UML. It indeed revealed a great number of objects and an intricate relationship. Use cases and object orientation were powerful techniques for the pre-analysis and analysis phases of a system development. They facilitated the communication between the developers and the users or domain experts and increased their cooperation in the modelling process. The models are easy to understand, even for those not used to systems modelling, since the notations are simple and the objects that appear on the model have their counterpart in the real world. From that analysis domain components could be identified and can be developed to build a component repository. Fig. 2 Class Diagram Use case Generate Output File 1307

6 Fig. 3 Subsystem Diagram 4 References Borim, Andrea C. A., Modelo orientado a objetos para sistemas abertos de informações que visam o gerenciamento de propriedades voltadas à produção de leite. 192p. PhD Thesis Universidade Federal de Uberlândia. Minas Gerais. /English title: Object oriented model for open information systems for the management of dairy farms/. Rumbaugh, J. et al., 1997 Modelagem e projetos baseados em objetos. Rio de Janeiro, Campus. (Portuguese version of Object-oriented modeling and design, Prentice Hall, 1991). Saraiva, A.M. et al., A use case driven domain analysis for precision agriculture information systems. In: 3rd International Multiconference on Circuits, Systems, Communications and Computers- IMACS/IEEE, Athens. Proceedings. Athens: World Scientific and Engineering Society Press, v. 1, p