• Title/Summary/Keyword: analysis and modeling

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State-Based Behavior Modeling in Software and Systems Engineering

  • Sabah Al-Fedaghi
    • International Journal of Computer Science & Network Security
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    • v.23 no.5
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    • pp.21-32
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    • 2023
  • The design of complex man-made systems mostly involves a conceptual modeling phase; therefore, it is important to ensure an appropriate analysis method for these models. A key concept for such analysis is the development of a diagramming technique (e.g., UML) because diagrams can describe entities and processes and emphasize important aspects of the systems being described. The analysis also includes an examination of ontological concepts such as states and events, which are used as a basis for the modeling process. Studying fundamental concepts allows us to understand more deeply the relationship between these concepts and modeling frameworks. In this paper, we critically analyze the classic definition of a state utilizing the Thinging machine (TM) model. States in state machine diagrams are considered the appropriate basis for modeling system behavioral aspects. Despite its wide application in hardware design, the integration of a state machine model into a software system's modeling requirements increased the difficulty of graphical representation (e.g., integration between structural and behavioral diagrams). To understand such a problem, in this paper, we project (create an equivalent representation of) states in TM machines. As a case study, we re-modeled a state machine of an assembly line system in a TM. Additionally, we added possible triggers (transitions) of the given states to the TM representation. The outcome is a complicated picture of assembly line behavior. Therefore, as an alternative solution, we re-modeled the assembly line based solely on the TM. This new model presents a clear contrast between state-based modeling of assembly line behavior and the TM approach. The TM modeling seems more systematic than its counterpart, the state machine, and its notions are well defined. In a TM, states are just compound events. A model of a more complex system than the one in the assembly line has strengthened such a conclusion.

Development and Hydraulic Characteristics of Continuous Block System in River Bank Protection (II) - Comparison of Numerical Analysis with Physical Modeling - (일체형 식생호안블록 시스템 개발 및 수리특성 연구(II) -일체형 호안블록시스템 수치모의를 통한 효과 분석-)

  • Jang, SukHwan
    • Journal of Wetlands Research
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    • v.10 no.3
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    • pp.99-109
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    • 2008
  • This research focused on analyzing and comparing between the results of hydraulic physical modeling and the results of numerical modeling of continuous block system in river bank protection which is newly developed in-situ block system. To verify the hydraulic physical modeling and review the effectiveness, the numerical modeling was needed against the model test results for vegetation application or not. HEC-RAS model was for 1 dimensional numerical analysis and SMS was for 2 dimensional numerical analysis. The results of the two dimensional numerical simulation, under the condition of roughness coefficient calibration, show similar and rational consequence against the physical modeling. These satisfactory results show that the accomplished results of hydraulic modeling and the predicted results of numerical modeling corresponded reasonably each others.

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Teacher Education for Mathematical Modeling: a Case Study (수학적 모델링의 구현을 위한 교사 교육: 사례 연구)

  • Kim, Yeon
    • East Asian mathematical journal
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    • v.36 no.2
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    • pp.173-201
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    • 2020
  • Mathematical modeling has been emphasized because it offers important opportunities for students to both apply their learning of mathematics to a situation and to explore the mathematics involved in the context of the situation. However, unlike its importance, mathematical modeling has not been grounded in typical mathematics classes because teachers do not have enough understanding of mathematical modeling and they are skeptical to implement it in their lessons. The current study analyzed the data, such as video recordings, slides, and surveys for teachers, collected in four lessons of teacher education in terms of mathematical modeling. The study reported different kinds of tasks that are authentic with regards to mathematical modeling. Furthermore, in teacher education, teachers' identities have separated a mode as learners and a mode as teachers and conflicts and intentional transition were observed. Analysis of the surveys shows what teachers think about mathematical modeling with their understanding of it. In teacher education, teachers achieved different kinds of modeling tasks and experience them which are helpful to enact mathematical modeling in their lessons. However, teacher education also needs to specifically offer what to do and how to do it for their lessons.

Dynamic Analysis of Simply Supported Flexible Structures Undergoing Large Overall Motion (전체운동을 하는 단순지지 유연 구조물의 동적해석)

  • 유홍희
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.6
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    • pp.1363-1370
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    • 1995
  • A nonlinear dynamic modeling method for simply supported structures undergoing large overall motion is suggested. The modeling method employs Rayleigh-Ritz mode technique and Von Karman nonlinear strain measures. Numerical study shows that the suggested modeling method provides qualitatively different results from those of the Classical Linear Cartesian modeling method. Especially, natural frequency variations and residual deformation due to membrane strain effects are observed in the numerical results obtained by the suggested modeling method.

Development of an Entity-Relationship Modeling System for Designing Relational Database (관계형 데이터베이스 설계를 위한 개체 - 관계 모델링 시스템 개발)

  • Yoo, Jae-Gun
    • IE interfaces
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    • v.16 no.spc
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    • pp.45-48
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    • 2003
  • Entity-relationship modeling for designing relational database is a very complicated thinking process that requires extensive knowledge and experiences. It is very likely that designers make mistakes in this process. In order to minimize the mistakes, a systematic method to guide the thinking process is needed. In this research, an entity-relationship modeling system is developed, which resolves the whole process of information modeling, data modeling, and functional dependency relationship analysis into small and simple decision-making steps. Therefore, it can reduce the possibility of making decision errors and improve the efficiency of the modeling process. It's functionality and efficiency is verified through some modeling examples. It is expected that the modeling system can be commercialized, if some functions are added, such as detection, warning, and correction of decision errors, and educational help.

Tolerance Analysis on 3-D Object Modeling Errors in Model-Based Camera Tracking (모델 기반 카메라 추적에서 3차원 객체 모델링의 허용 오차 범위 분석)

  • Rhee, Eun Joo;Seo, Byung-Kuk;Park, Jong-Il
    • Journal of Broadcast Engineering
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    • v.18 no.1
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    • pp.1-9
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    • 2013
  • Accuracy of the 3-D model is essential in model-based camera tracking. However, 3-D object modeling requires dedicated and complicated procedures for precise modeling without any errors. Even if a 3-D model contains a certain level of errors, on the other hand, the tracking errors cause by the modeling errors can be different from its perceptual errors; thus, it is an important aspect that the camera tracking can be successful without precise 3-D modeling if the modeling errors are within the user's permissible range. In this paper, we analyze the tolerance of 3-D object modeling errors by comparing computational matching errors with perceptual matching errors through user evaluations, and also discuss permissible ranges of 3-D object modeling errors.

Simulation of Groundwater Variation Characteristics of Hancheon Watershed in Jeju Island using Integrated Hydrologic Modeling (통합수문모형을 이용한 제주 한천유역의 지하수 변동 특성 모의)

  • Kim, Nam-Won;Na, Hanna;Chung, Il-Moon
    • Journal of Environmental Science International
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    • v.22 no.5
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    • pp.515-522
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    • 2013
  • To investigate groundwater variation characteristics in the Hancheon watershed, Jeju Island, an integrated hydrologic component analysis was carried out. For this purpose, SWAT-MODFLOW which is an integrated surface-groundwater model was applied to the watershed for continuous watershed hydrologic analysis as well as groundwater modeling. First, ephemeral stream characteristics of Hancheon watershed can be clearly simulated which is unlikely to be shown by a general watershed hydrologic model. Second, the temporally varied groundwater recharge can be properly obtained from SWAT and then spatially distributed groundwater recharge can be made by MODFLOW. Finally, the groundwater level variation was simulated with distributed groundwater pumping data. Since accurate recharge as well as abstraction can be reflected into the groundwater modeling, more realistic hydrologic component analysis and groundwater modeling could be possible.

Data-driven modeling of optimal intensity measure of soil-nailed wall structures

  • Massoumeh Bayat;Mahdi Bayat;Mahmoud Bayat
    • Structural Engineering and Mechanics
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    • v.86 no.1
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    • pp.85-92
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    • 2023
  • This article examines the seismic vulnerability of soil nail wall structures. Detailed information regarding finite element modeling has been provided. The fragility function evaluates the relationship between ground motion intensities and the probability of surpassing a specific level of damage. The use of incremental dynamic analysis (IDA) has been applied to the soil nail wall against low to severe ground motions. In the nonlinear dynamic analysis of the soil nail wall, a set of twenty seismic ground motions with varying PGA ranges are used. The numerical results demonstrate that the soil-nailed wall reaction is extremely sensitive to earthquake ground vibrations under different intensity measures (IM). In addition, the analytical fragility curve is provided for various intensity values.

Essential Logical Model Approach in Analysis and Design for Patient Management and Accounting System : A Case Study (본질적 논리모형에 근거한 원무관리시스템의 분석과 설계)

  • 김명기
    • Health Policy and Management
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    • v.4 no.2
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    • pp.111-125
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    • 1994
  • In developing total hospital information system, large amount of time and expense are to be spent while its results are likely to lead itself to end-users' dissatisfaction. Some of the main complaints on the part of end-users come from insufficient consideration of end-users environment as well as inappropriate representation of their requirement in the system alalysis and design. This papre addresses some advantages of Essential Logical Modeling Process for better analysis and design, explaining by example the developmental process of the Patent Management and Accounting System for a tertiary care hospital. In the case, the Essential Model, suggested by McMenamin and Palmer, proved to be an effective tool for clear separation of analysis and design phase and for better communication among system developers and with end-users. The modeling process itself contributed to better program modularity as well, shown in a Structured Chart. Difficulties in learning how to identify' essential activities' for the modeling practice were experienced in the beginnins stage, which were, however, overcome by elaborating some heuristic guideling and by rdferring to necessary tools including State Transition Diagram, Control Flow Diagram, and so many. While full evaluation of the Essential Model usag remains to wait till the completion of the case project, its strengt in making clear distinction between analysis and design phase was enough to be attractive to system analysts. The model concepts are open to many further application fields, particularly such areas as business re engineering, process remodeling, office automation, and organizational restructuring.

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Topic Modeling and Sentiment Analysis of Twitter Discussions on COVID-19 from Spatial and Temporal Perspectives

  • AlAgha, Iyad
    • Journal of Information Science Theory and Practice
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    • v.9 no.1
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    • pp.35-53
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    • 2021
  • The study reported in this paper aimed to evaluate the topics and opinions of COVID-19 discussion found on Twitter. It performed topic modeling and sentiment analysis of tweets posted during the COVID-19 outbreak, and compared these results over space and time. In addition, by covering a more recent and a longer period of the pandemic timeline, several patterns not previously reported in the literature were revealed. Author-pooled Latent Dirichlet Allocation (LDA) was used to generate twenty topics that discuss different aspects related to the pandemic. Time-series analysis of the distribution of tweets over topics was performed to explore how the discussion on each topic changed over time, and the potential reasons behind the change. In addition, spatial analysis of topics was performed by comparing the percentage of tweets in each topic among top tweeting countries. Afterward, sentiment analysis of tweets was performed at both temporal and spatial levels. Our intention was to analyze how the sentiment differs between countries and in response to certain events. The performance of the topic model was assessed by being compared with other alternative topic modeling techniques. The topic coherence was measured for the different techniques while changing the number of topics. Results showed that the pooling by author before performing LDA significantly improved the produced topic models.