Modeling events as entities in object-oriented conceptual modeling languages

Most current conceptual modeling languages and methods do not model events as entities. We argue that, at least in object-oriented (O-O) languages, modeling events as entities provides substantial benefits. We show that a method for behavioral modeling that deals with event and entity types in a uniform way may yield better behavioral schemas. The proposed method makes extensive use of language constructs such as constraints, derived types, derivation rules, type specializations and operations, which are present in all complete O-O conceptual modeling languages. The method can be adapted to most O-O languages. In this paper we explain its adaptation to the UML.     

Modeling irregular boundary with transmission‐line modeling method

This work proposes a model to represent internal and external fractional boundary nodes without increasing the computational time and memory comparing to other techniques. The limiting effects on the simulation time steps are the same of the basic transmission‐line nodes. This model is also indicated for parallel processing, once it does not produce branching in the algorithm stream. The processing time is the same as a basic transmission‐line modeling (conventional TLM) mesh independent of the boundary complexity. The accuracy is higher than the one obtained with the basic TLM (full nodes). This model is suitable for hybrid and general TLM symmetrical condensed nodes. Validations are made against analytical results, numerical TLM results (conventional TLM), and other published results. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.     

联锁软件的统一建模语言和Petri网建模

使用统一建模语言(unified modeling language,UML)为联锁软件建立平台无关的模型(platform independent model．PIM),可以实现在异种平台间的移植和复用,并有助于自动生成测试案例和测试脚本。UML建模包括静态结构分析和动态行为分析。Petri网可对联锁软件与安全性相关的动态行为精确和严格地进行形式化描述。     

Modeling collaboration protocols for collaborative modeling tools: Experiences and applications

Over the last two decades, Collaborative Systems have become increasingly popular thanks to the many advances made in networks, communications and software tools. Within this field, Collaborative Modeling Systems apply the collaborative paradigm to the construction of (often visual) models, where users build diagrams from building blocks and the relationships between them. In these kinds of applications, the work is usually arranged into sessions, with the definition of some kind of time organization between those sessions. This organization is known as a collaboration protocol. Unfortunately, it is not usually easy to define these protocols, and many applications do not allow users to make any use of them.In an effort to overcome these difficulties, in this paper we propose a visual language for defining collaboration protocols for these systems. As such, in our language, sessions, artifacts and the transformations between them can be specified visually, and different coordination relationships (such as fork and join) can be defined. The visual language is included in a development method for collaborative systems that take advantage of the Eclipse platform in order to develop model-driven graphical editors that are enhanced with collaboration capabilities.     

基于多模型数据融合算法的木材干燥过程建模

提出了一种适合木材干燥过程建模的多模型数据融合算法,通过该方法构建了数据融合模型。分别用BP神经网络和动态递归网络建立了木材干燥基准模型,利用自适应加权算法对两模型输出进行融合,通过实验干燥数据仿真表明:融合后的木材含水率预测值的方差为0.125 3,高于任何一个单独模型的预测精度。     

A complex mathematical modeling method for biological objects. Modeling the tundra community

We consider a method for mathematical modeling of ecologo-biological systems based on computational studies that unites formal and informal, analytic and imitational approaches. The method is based on complex studies that include a complete set of operations, from filtering biological information to constructing a set of interrelated models, including simplified ones, that admit an analytic (parametric) study. This lets us overcome the disadvantages of purely imitational approaches: they are restricted by numerical experiments and often have huge models. The proposed approach has been used to analyze animal population fluctuations with the tundra community model “vegetation-lemmings-arctic foxes.” As a result of our studies, we formulate hypotheses on leading mechanisms that determine the fluctuations of tundra animal populations.     

A software engineering perspective on environmental modeling framework design: The Object Modeling System

The environmental modeling community has historically been concerned with the proliferation of models and the effort associated with collective model development tasks (e.g., code generation, data transformation, etc.). Environmental modeling frameworks (EMFs) have been developed to address this problem, but much work remains before EMFs are adopted as mainstream modeling tools. Environmental model development requires both scientific understanding of environmental phenomena and software developer proficiency. EMFs support the modeling process through streamlining model code development, allowing seamless access to data, and supporting data analysis and visualization. EMFs also support aggregation of model components into functional units, component interaction and communication, temporal-spatial stepping, scaling of spatial data, multi-threading/multi-processor support, and cross-language interoperability. Some EMFs additionally focus on high-performance computing and are tailored for particular modeling domains such as ecosystem, socio-economic, or climate change research. The Object Modeling System Version 3 (OMS3) EMF employs new advances in software framework design to better support the environmental model development process. This paper discusses key EMF design goals/constraints and addresses software engineering aspects that have made OMS3 framework development efficacious and its application practical, as demonstrated by leveraging software engineering efforts outside of the modeling community and lessons learned from over a decade of EMF development. Software engineering approaches employed in OMS3 are highlighted including a non-invasive lightweight framework design supporting component-based model development, use of implicit parallelism in system design, use of domain specific language design patterns, and cloud-based support for computational scalability. The key advancements in EMF design presented herein may be applicable and beneficial for other EMF developers seeking to better support environmental model development through improved framework design.     

Modeling the user's conceptual knowledge in BGP-MS,a user modeling shell system1

The paper describes the modeling of a user's conceptual knowledge in the general user modeling shell system BGP-MS. On the one hand, BGP-MS is a workbench for the develment of a user model in a particular application domain. It supports the definition of the architecture of the individual user model, and of the architecture and the contents of user stereotypes. A rich representation language for conceptual knowledge, a partition mechanism, and flexible graphics-based interfaces are at the disposal of the user model developer. On the other hand, BGP-MS is a runtime user modeling tool aimed at fulfilling central tasks of a user modeling component in an application system. In this mode, the system offers a functional interface for accessing and updating the model of the current user, as well as basic domain-independent inference mechanisms, support for inferences defined by the developer, and a customizable stereotype management utility. The usefulness of BGP-MS will be demonstrated by illustrating how it can support the user modeling of various recently developed application systems.     

Modeling task completion time of in-vehicle information systems while driving with keystroke level modeling

The use of touchscreen-based in-vehicle information systems (IVIS) is increasing. To ensure safe driving, it is important to evaluate IVIS task performance during driving situations. Therefore, we proposed a model to assess the task completion time (TCT) of IVIS tasks while driving using a keystroke-level modeling (KLM) technique. The basic assumptions and heuristic rules of driver behaviors were considered. In addition, based on the characteristics of visual and manual IVIS interactions, we determined the basic unit operators (i.e., visual, manual, and mental operators). User experiments were conducted to determine the individual execution times of unit tasks and to measure the TCT of IVIS tasks while driving. Based on the heuristic rules for model development and individual task execution times, we derive a predictive model for the TCT of IVIS tasks. We used a regression analysis to validate the modeling procedure, showing that the observed TCT was found to have a strong positive correlation with the predicted time from the modeling process. The findings showed that the task completion time needed to perform a secondary task in a driving context can be predicted by KLM. This study provides meaningful insights into the design of touchscreen-based IVIS to enhance driving safety.     

Modeling airborne laser scanning data for the spatial generation of critical forest parameters in fire behavior modeling

Methods for using airborne laser scanning (also called airborne LIDAR) to retrieve forest parameters that are critical for fire behavior modeling are presented. A model for the automatic extraction of forest information is demonstrated to provide spatial coverage of the study area, making it possible to produce 3-D inputs to improve fire behavior models.The Toposys I airborne laser system recorded the last return of each footprint (0.30-0.38 m) over a 2000 m by 190 m flight line. Raw data were transformed into height above the surface, eliminating the effect of terrain on vegetation height and allowing separation of ground surface and crown heights. Data were defined as ground elevation if heights were less than 0.6 m. A cluster analysis was used to discriminate crown base height, allowing identification of both tree and understory canopy heights. Tree height was defined as the 99 percentile of the tree crown height group, while crown base height was the 1 percentile of the tree crown height group. Tree cover (TC) was estimated from the fraction of total tree laser hits relative to the total number of laser hits. Surface canopy (SC) height was computed as the 99 percentile of the surface canopy group. Surface canopy cover is equal to the fraction of total surface canopy hits relative to the total number of hits, once the canopy height profile (CHP) was corrected. Crown bulk density (CBD) was obtained from foliage biomass (FB) estimate and crown volume (CV), using an empirical equation for foliage biomass. Crown volume was estimated as the crown area times the crown height after a correction for mean canopy cover.     

Solid modeling

Solid modeling deals with the representation, design, visualization. and analysis of models of 3D parts. While the embodiment of solid modeling technology in contemporary commercial CAD systems is finally beginning to fulfil the old promise of providing major improvements in the productivity of the manufacturing industry, solid modeling research remains in its infancy. Recent developments focus on advanced design paradigms, topological and geometric extensions of the domain and the performance and reliability of the fundamental algorithms. The current trend follows two paths: capitalizing on the concepts of features, constraints, and model parameterization, which provide a more intuitive and suitable design vocabulary than the traditional edges, faces, or Boolean operations; and incorporating information about the tolerances, assembly relations, and mechanical properties of parts and assemblies, which provides a suitable product database for the development of analysis and planning applications. We selected the articles in the special issue carefully, choosing from among the papers presented at the 1993 ACM/IEEE Second Symposium on Solid Modeling and Applications     

Expectation-oriented modeling

This work introduces expectation-oriented modeling (EOM) as a conceptual and formal framework for the modeling and influencing of black- or gray-box agents and agent interaction from the viewpoint of modelers like artificial agents and application designers. EOM is unique in that autonomous agent behavior is not restricted in advance, but only if it turns out to be necessary at runtime, and does so exploiting a seamless combination of evolving probabilistic and normative behavioral expectations as the key modeling abstraction and as the primary level of analysis and influence. Expectations are attitudes which allow for the relation of observed actions and other events to the modelers intentions and beliefs in an integrated, adaptive manner. In this regard, this work introduces a formal framework for the representation and the semantics of expectations embedded in social contexts. We see the applicability of EOM especially in open domains with a priori unknown and possibly unreliable and insincere actors, where the modeler cannot rely on cooperation or pursue her goals through the exertion of strictly normative power, e.g. the development and assertion of flexible interaction policies for trading platforms in the Internet, as illustrated in a case study. To our knowledge, EOM is the first approach to the modeling, cognitive analysis and influencing of social interaction that aims at tackling the level of expectations explicitly and systematically.     

统一建模语言UML及其建模实例

以统一建模语言（Unified Modeling Language,UML)的九种图为重点，简要介绍了UML的基本概念、历史、内容及其应用；并通过对一个超级市场销售管理系统的实际建模，简要演示了应用UML建模的思路。     

喷泉景观的造型设计与模型研究

在分析现有喷泉模拟的基础上，针对喷泉造型的研究相对较少的问题，进行了喷泉造型设计并建模。运用多种数学曲线、曲面方程建立了复杂特殊的喷泉造型模型，并分析喷泉粒子的运动特性建立了喷泉运动模型。采用Visual Studio为编程工具，结合OpenGL技术渲染场景，在Windows XP环境下开发了基于粒子系统的喷泉模拟系统，仿真效果真实。