Best practices for conceptual modelling in environmental planning and management

Conceptual modelling is used in many fields with a varying degree of formality. In environmental applications, conceptual models are used to express relationships, explore and test ideas, check inference and causality, identify knowledge and data gaps, synchronize mental models and build consensus, and to highlight key or dominant processes. Due to their sometimes apparent simplicity, development and use of a conceptual model is often an attractive option when tackling an environmental problem situation. However, we have experienced many examples where conceptual modelling has failed to effectively assist in the resolution of environmental problems. This paper explores development and application of conceptual modelling to environmental problems, and identifies a range of best practices for environmental scientists and managers that include considerations of stakeholder participation and trust, model development and representation, integration of different and disparate conceptual models, model maturation, testing, and transition to application within the problem situation.     

Conceptual document modelling and retrieval

This paper presents the main current theoretical issues in Information Retrieval. The principles of conceptual modelling, as they have emerged in the database area, are presented and their application to document modelling in order to enhance document retrieval is discussed. Finally, the main features of the MULTOS project are presented and critically reviewed confronting them with the requirements which have been identified during the general discussion on document conceptual modelling for information retrieval.     

Metainformation scenarios in Digital Humanities: Characterization and conceptual modelling strategies

Requirements for the analysis, interpretation and reuse of information are becoming more and more ambitious as we generate larger and more complex datasets. This is leading to the development and widespread use of information about information, often called metainformation (or metadata) in most disciplines. The Digital Humanities are not an exception. We often assume that metainformation helps us in documenting information for future reference by recording who has created it, when and how, among other aspects. We also assume that recording metainformation will facilitate the tasks of interpreting information at later stages. However, some works have identified some issues with existing metadata approaches, related to 1) the proliferation of too many “standards” and difficulties to choose between them; 2) the generalized assumption that metadata and data (or metainformation and information) are essentially different, and the subsequent development of separate sets of languages and tools for each (introducing redundant models); and 3) the combination of conceptual and implementation concerns within most approaches, violating basic engineering principles of modularity and separation of concerns. Some of these problems are especially relevant in Digital Humanities.In addition, we argue here that the lack of characterization of the scenarios in which metainformation plays a relevant role in humanistic projects often results in metainformation being recorded and managed without a specific purpose in mind. In turn, this hinders the process of decision making on issues such as what metainformation must be recorded in a specific project, and how it must be conceptualized, stored and managed.This paper presents a review of the most used metadata approaches in Digital Humanities and, taking a conceptual modelling perspective, analyses their major issues as outlined above. It also describes what the most common scenarios for the use of metainformation in Digital Humanities are, presenting a characterization that can assist in the setting of goals for metainformation recording and management in each case. Based on these two aspects, a new approach is proposed for the conceptualization, recording and management of metainformation in the Digital Humanities, using the ConML conceptual modelling language, and adopting the overall view that metainformation is not essentially different to information. The proposal is validated in Digital Humanities scenarios through case studies employing real-world datasets.     

On qualitative modelling

Fundamental assumptions behind qualitative modelling are critically considered and some inherent problems in that modelling approach are outlined. The problems outlined are due to the assumption that a sufficient set of symbols representing the fundamental features of the physical world exists. That assumption causes serious problems when modelling continuous systems. An alternative for intelligent system building for cases not suitable for qualitative modelling is proposed. The proposed alternative combines neural networks and quantitative modelling.     

An integrated modelling environment for the embodiment of mechanical systems

The efficient, economical and often elegant transformation from a design schema to an embodied design solution containing real components is essential for the commercial success of a product. More often the ability of the designer to explore an optimum solution is severely frustrated by the analytically intensive and time-consuming aspects of embodying a concept. This paper presents a computer based system-modelling tool that is to be used by designers during the transformation of a concept to an embodied solution particularly to deal with standard components. This environment provides for the representation of conceptual schemas and subsequent embodiment from computer based component selection modules. These selection modules encompass the full range of electronic representations for standard mechanical components. The strategy for representing a mechanical system, its included components and their associated representations is discussed. The process of constructing a system model, specifying the desired performance characteristics and system resolution are also described.     

非整数阶系统连续时间域的模拟

提出了一种致力于非整数阶系统连续时间域的模拟方法.这种特殊系统的仿真建立在有限频率区间非整数阶积分算子的基础上,其非整数阶作用仅限于有限频率区域.然后,可以定义非整数阶模型的状态方程实现,它允许近似理想非整数阶系统的连续时间响应.最后,通过两个数字仿真例子来验证这种模拟方法.     

Computationally efficient modelling of tidal rivers using conceptual reservoir-type models

Conceptual reservoir-type models of river systems, that mimic the results of detailed hydrodynamic models, provide a powerful tool for numerous river management applications. Thanks to their computationally efficient model structure they are very well suited for applications that require long term simulations or a large number of model iterations. However, one well-known problem is that conceptual models have difficulties to account for backwater effects. For this reason, their application to tidally influenced river reaches so far was almost non-existent. This paper introduces an extension of an existing grey-box reservoir modelling technique to incorporate tidally influenced river reaches. The methodology is demonstrated for the downstream part of the rivers Zenne and Rupel in Belgium. Results show a minor loss of accuracy when the detailed model is replaced by the surrogate conceptual model. Also, the tidal effects are well represented.     

Maintaining knowledge with a formal model

Knowledge base maintenance is managed by constructing a formal model. In this model the representation of each chunk of knowledge encapsulates the knowledge in a set of declarative rules, each of which in turn encapsulates the knowledge in a set of imperative programs. In this model an “item” is the unit of knowledge representation. Items are at a higher level of abstraction than rules. Understanding what has to be done to maintain the integrity of an item leads to a specification of the modifications to the set of programs that implement it. An analysis of the maintenance of the formal model is achieved by introducing maintenance links. Analysis of the maintenance links shows that they are of four different types. The density of the maintenance links is reduced by transforming that set into an equivalent set. In this way the knowledge base maintenance problem is analysed and simplified. A side benefit of knowledge items as a formalism is that they contain knowledge constraints that protect the knowledge from unforeseen modification.     

Reasoning with direction and rate of change in vegetation state transition modelling

Better integration in land planning and management can be supported through the use of suitable model-based tools. Vegetation state transition models have been noted as being useful in this context, providing a simple, useful means of capturing available ecological knowledge. We describe a simple ‘proof of concept’ rule-based system developed to contribute methodologically to management-oriented modelling of vegetated landscapes. The system is based upon a clear separation of direction from rate of change and the use of a general temporal reasoning system, a feature that facilitates modelling of situations where environmental change occurs causing an increase or decrease in rate without affecting direction of vegetation change. To ease model development and use the system represents vegetation dynamics in a way that has a close correspondence to the structure of understanding communicated by vegetation ecologists. A test model is described and run under different conditions to demonstrate the system. The results show that although the rule-based system and in particular the temporal reasoning system used operate successfully, there are a number of deficiencies in the modelling system as currently implemented. Future development possibilities are detailed along with a broader discussion regarding the needs of management-oriented modelling and the utility of state transition approaches.     

Student modelling in intelligent tutoring systems

Student modelling is a special type of user modelling which is relevant to the adaptability of intelligent tutoring systems. This paper reviews the basic techniques which have been used in student modelling and discusses issues and approaches of current interest. The role of a student model in a tutoring system and methods for representing information about students are discussed. The paper concludes with an overview of some unresolved issues and problems in student modelling.Electric Brain Company     

User modelling and user adapted interaction in an intelligent tutoring system

User modelling and user-adapted interaction are crucial to the provision of true individualised instruction, which intelligent tutoring systems strive to achieve. This paper presents how user (student) modelling and student adapted instruction is achieved in FITS, an intelligent tutoring system for the fractions domain. Some researchers have begun questioning both the need for detailed student models as well as the pragmatic possibility of building them. The key contributions of this paper are in its attempt to rehabilitate student modelling/adaptive tutoring within ITSs and in FITS's practical use of simple techniques to realise them with seemingly encouraging results; some illustrations are given to demonstrate the latter.     

Automatic speech grammar generation during conceptual modelling of virtual environments

Speech interfaces are becoming more and more popular as a means to interact with virtual environments but the development and integration of these interfaces is usually still ad hoc, especially the speech grammar creation of the speech interface is a process commonly performed by hand. In this paper, we introduce an approach to automatically generate a speech grammar which is generated using semantic information. The semantic information is represented through ontologies and gathered from the conceptual modelling phase of the virtual environment application. The utterances of the user will be resolved using queries onto these ontologies such that the meaning of the utterance can be resolved. For validation purposes we augmented a city park designer with our approach. Informal tests validate our approach, because they reveal that users mainly use words represented in the semantic data, and therefore also words which are incorporated in the automatically generated speech grammar.

Cold start modelling of spark ignition engines

The ability of mean value models to replicate the key characteristics of automotive powertrains has been well established over the past four decades. There has been considerable success in the application of these models to controller design, with improved emissions and performance of the primary benefits. However, these low order models typically must make certain assumptions about the engine—with constant temperature operation a standard approximation. As economy and emissions at every point in the drive cycle become scrutinised, the cold start operation of the engine becomes more critical and the constant temperature assumption is limiting. This paper seeks to develop a model framework for capturing the temperature transients and gaseous concentrations throughout the engine. A methodology for calibrating the model is also presented, and uses a combination of steady state and transient testing. Finally, certain states in the full model are eliminated to produce a family of reduced order models, with the intention of outlining the minimum complexity required for control and optimisation studies with differing objectives.     

Progressive surface modelling scheme from unorganised curves

This paper presents a novel surface modelling scheme to construct a freeform surface progressively from unorganised curves representing the boundary and interior characteristic curves. The approach can construct a base surface model from four ordinary or composite boundary curves and support incremental surface updating from interior characteristic curves, some of which may not be on the final surface. The base surface is first constructed as a regular Coons surface and upon receiving an interior curve sketch, it is updated. With this progressive modelling scheme, a final surface with multiple sub-surfaces can be obtained from a set of unorganised curves and transferred to commercial surface modelling software for detailed modification. The approach has been tested with examples based on 3D motion sketches; it is capable of dealing with unorganised design curves for surface modelling in conceptual design. Its limitations have been discussed.     

State of research in automatic as-built modelling

Building Information Models (BIMs) are becoming the official standard in the construction industry for encoding, reusing, and exchanging information about structural assets. Automatically generating such representations for existing assets stirs up the interest of various industrial, academic, and governmental parties, as it is expected to have a high economic impact. The purpose of this paper is to provide a general overview of the as-built modelling process, with focus on the geometric modelling side. Relevant works from the Computer Vision, Geometry Processing, and Civil Engineering communities are presented and compared in terms of their potential to lead to automatic as-built modelling.     

Texture modelling applications

The paper describes a technique by which realistic textures can be constructed from a statistical model. It further tells us, in principle, how to map the texture onto a surface of any shape, maintaining consistency and scaling, without producing repeating patterns. It describes how a method designed earlier for grey scales alone can be extended to the colour case. The generalization of the former work to macroscopic textures is also presented. An application of this method to the Design is finally shown.