• Title/Summary/Keyword: Space-Time Integrated Model

Search Result 75, Processing Time 0.032 seconds

A Study on the Integrated Hybrid Spatial Model for Knowledge Information Institutions - Focused on the User Space of Public Library - (지식정보시설의 통합형 하이브리드 공간 모형 연구 - 공공도서관 이용자 공간을 중심으로 -)

  • Hwang, Mee-Young
    • Korean Institute of Interior Design Journal
    • /
    • v.24 no.3
    • /
    • pp.146-155
    • /
    • 2015
  • It is an undeniable fact that the modern people's interest in knowledge and information and their roles are some of the core factors used to define the modern society. Besides, as phenomena indicating and leading the modern society, we have fusion, hybrid and convergence, etc. that combine several different elements into a new one. Such changes in social, cultural and technological circumstances require a paradigm shift for the composition of knowledge and information facilities and space. However, more diversified and advanced recently, interfaces for the delivery of knowledge and information cause users to show new behaviors and even change the spatial concept with space composition elements hybridized. Especially for the space of libraries, it is necessary to access and utilize any forms of knowledge and information data (digital + analog) regardless of time and space limitations and approach with an integrated spatial concept likely to change flexibly depending on social demands. In this light, this study aims to make a basic proposal for sustainable integrated-type hybrid space for the space of a public library in this era of knowledge and information. Particularly, this study intends to seek a way to establish a hybrid space model that can effectively converge the most important factors of the space of libraries (human-space(network)-information). With 18 different cases, this study analyzed knowledge and information composition systems, knowledge and information delivery systems and users' space systems. As a result, this study extracted 3 kinds of models, an information-based model, a culture-based model and an education-based model, with the integrated hybrid space model of knowledge and information facilities

The Integration of Mobile GIS and Spatio-temporal Database for Evaluating Space-time Accessibility of an Individual: An Approach Based on Time Geography Model

  • Lee Yang-Won;Shibasaki Ryosuke
    • Proceedings of the KSRS Conference
    • /
    • 2005.10a
    • /
    • pp.753-758
    • /
    • 2005
  • This study attempts at building an integrated GIS computing framework for evaluating space-time accessibility of an individual with the approach of time geography model. The proposed method is based on the integration of mobile GIS and object-relational spatio-temporal database. Three components are central to our system: ( i ) mobile GIS application that transmits spatio-temporal trajectory data of an individual; ( ii ) spatio-temporal database server that incorporates the time geography model; and (iii) geovisualization client that provides time geographic queries to the spatio-temporal database. As for the mobile GIS application, spatio-temporal trajectory data collected by GPS-PDA client is automatically transmitted to the database server through mobile data management middleware. The spatio-temporal database server implemented by extending a generic DBMS provides spatio-temporal objects, functions and query languages. The geovisualization client illustrates 3D visual results of the queries about space-time path. space-time prism and space-time accessibility. This study shows a method of integrating mobile GIS and DBMS for time geography application, and presents an appropriate spatio-temporal data model for evaluating space-time accessibility of an individual.

  • PDF

Integrated Guidance and Control Design for the Near Space Interceptor

  • WANG, Fei;LIU, Gang;LIANG, Xiao-Geng
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.16 no.2
    • /
    • pp.278-294
    • /
    • 2015
  • Considering the guidance and control problem of the near space interceptor (NSI) during the terminal course, this paper proposes a three-channel independent integrated guidance and control (IGC) scheme based on the backstepping sliding mode and finite time disturbance observer (FTDO). Initially, the three-channel independent IGC model is constructed based on the interceptor-target relative motion and nonlinear dynamic model of the interceptor, in which the channel coupling term and external disturbance are regarded as the total disturbances of the corresponding channel. Then, the FTDO is introduced to estimate the target acceleration and control system loop disturbances, and the feed-forward compensation term based on the estimated values is employed to effectively remove the effect of disturbances in finite time. Subsequently, the IGC algorithm based on the backstepping sliding mode is also given to obtain the virtual control moment. Furthermore, a robust least-squares weighted control allocation (RLSWCA) algorithm is employed to distribute the previous virtual control moment among the corresponding aerodynamic fins and reaction jets, which also takes into account the uncertainty in the control effectiveness matrix. Finally, simulation results show that the proposed IGC method can obtain the small miss distance and smooth interceptor trajectories.

Distributed and Real-time Integrated Simulation System on Avionics

  • Zhou, Yaoming;Liu, Yaolong;Li, Shaowei;Jia, Yuhong
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.18 no.3
    • /
    • pp.574-578
    • /
    • 2017
  • In order to achieve iterative design in early R&D period, a Distributed and Real-time Integrated Simulation System for avionics based on a Model-Based Systems Engineering (MBSE) method is proposed. The proposed simulation system includes driver, simulation model, monitor, flight visual model and aircraft external model.The effect of this simulation system in iterative design and system verification is testified by several use cases. The result shows that the simulation system, which can play an important role in iterative design and system verification, can reduce project costs and shorten the entire R&D period.

QUANTITATIVE ANALYSES USING 4D MODELS - AN EXPLORATIVE STUDY

  • Rogier Jongeling;Jonghoon Kim;Claudio Mourgues;Martin Fischer;Thomas Olofsson
    • International conference on construction engineering and project management
    • /
    • 2005.10a
    • /
    • pp.830-835
    • /
    • 2005
  • 4D models help construction planners to develop and evaluate construction plans. However, current analyses using 4D models are mainly visual and limit the quantitative comparison of construction alternatives. This paper explores the usefulness of extracting quantitative information from 4D models to support time-space analyses. We use two 4D models of an industry test case to illustrate how to analyze 4D content quantitatively (i.e., work space areas and distances between concurrent activities). This paper shows how these two types of 4D content can be extracted from 4D models to support 4D-based-analysis and novel presentation of construction planning information. We suggest further research to formalize the content of 4D models to enable comparative quantitative analyses of construction planning alternatives. Formalized 4D content will enable the development of reasoning mechanisms that automate 4D-model-based analyses and provide the information content for informative presentations of construction planning information.

  • PDF

Integrated Roll-Pitch-Yaw Autopilot via Equivalent Based Sliding Mode Control for Uncertain Nonlinear Time-Varying Missile

  • AWAD, Ahmed;WANG, Haoping
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.18 no.4
    • /
    • pp.688-696
    • /
    • 2017
  • This paper presents an integrated roll-pitch-yaw autopilot using an equivalent based sliding mode control for skid-to-turn nonlinear time-varying missile system with lumped disturbances in its six-equations of motion. The considered missile model are developed to integrate the model uncertainties, external disturbances, and parameters perturbation as lumped disturbances. Moreover, it considers the coupling effect between channels, the variation of missile velocity and parameters, and the aerodynamics nonlinearity. The presented approach is employed to achieve a good tracking performance with robustness in all missile channels simultaneously during the entire flight envelope without demand of accurate modeling or output derivative to avoid the noise existence in the real missile system. The proposed autopilot consisting of a two-loop structure, controls pitch and yaw accelerations, and stabilizes the roll angle simultaneously. The Closed loop stability is studied. Numerical simulation is provided to evaluate performance of the suggested autopilot and to compare it with an existing autopilot in the literature concerning the robustness against the lumped disturbances, and the aforesaid considerations. Finally, the proposed autopilot is integrated in a six degree of freedom flight simulation model to evaluate it with several target scenarios, and the results are shown.

Forecasting with a combined model of ETS and ARIMA

  • Jiu Oh;Byeongchan Seong
    • Communications for Statistical Applications and Methods
    • /
    • v.31 no.1
    • /
    • pp.143-154
    • /
    • 2024
  • This paper considers a combined model of exponential smoothing (ETS) and autoregressive integrated moving average (ARIMA) models that are commonly used to forecast time series data. The combined model is constructed through an innovational state space model based on the level variable instead of the differenced variable, and the identifiability of the model is investigated. We consider the maximum likelihood estimation for the model parameters and suggest the model selection steps. The forecasting performance of the model is evaluated by two real time series data. We consider the three competing models; ETS, ARIMA and the trigonometric Box-Cox autoregressive and moving average trend seasonal (TBATS) models, and compare and evaluate their root mean squared errors and mean absolute percentage errors for accuracy. The results show that the combined model outperforms the competing models.

Implementation of GPS/Galileo Integrated Navigation Algorithm and Analysis of Different Time-Coordinate Effect (GPS/Galileo 통합항법알고리즘 구현 및 시각 및 좌표계차이에 따른 영향분석)

  • Song, Jong-Hwa;Jee, Gyu-In;Jeong, Seong-Kyun;Lee, Sang-Uk;Kim, Jae-Hoon
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.36 no.2
    • /
    • pp.171-178
    • /
    • 2008
  • Galileo is the Europe's global navigation satellite system corresponding to the GPS. The GIOVE-A test experiment has been finished and the second test satellite GIOVE-B will be launched soon. The integration of GPS and Galileo lead an increase of visible satellite number. We can obtain an improved navigation performance in signal blocked area such as urban or forest. GPS and Galileo have each time-coordinate system and use the different error model to calculate the navigation solution. In this paper, we studied on GPS and Galileo channel error model and time-coordinate system. Using this result, we implement the integrated navigation algorithm. In simulation, we analyzed the navigation error caused by time and coordinate disagreement and verified performance of integrated navigation algorithm in terms of visible satellite number, DOP(Dilution of Pression) and position error.

A Pedestrian Network Assignment Model Considering Space Syntax (공간구문론(Space Syntax)을 고려한 통합보행네트워크 통행배정모형)

  • Lee, Mee Young;Kim, Jong Hyung;Kim, Eun Jung
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.14 no.6
    • /
    • pp.37-49
    • /
    • 2015
  • In Space Syntax, the greater the degree of integration between separate links, the greater the links' accessibility from the target network. As such, planning pedestrian walks so that links with high degrees of integration are connected, or else inducing high integration value land use are both valid options. The travel distribution model reflects how walking demand, or more specifically, the pedestrian, partakes in route choosing behavior that minimizes select criteria, notably level of discomfort, as measured using travel distance and time. The model thus demonstrates travel patterns associated with demand pertaining to minimization of discomfort experienced by the pedestrian. This research introduces a method that integrates Space Syntax and the pedestrian travel distribution model. The integrated model will determine whether regions with high degrees of integration are actually being used as pivots for pedestrian demand movement, as well as to explain whether the degree of integration is sustained at an appropriate level while considering actual movement demand. As a means to develop the integrated model, a method that combines display of the visibility of the space syntax network and road-divided links is proposed. The pedestrian travel distribution model also includes an alternative path finding mechanism between origin and destination, which allows for uniform allocation of demand.