• 산업경영시스템학회지
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• 제17권30호
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• pp.167-175
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• 1994

Generally, queueing networks, networks, chains and simulation techniques are among the most widely used evaluation tools to study computer systems, manufacturing systems etc. But, these tools have some assumptions and difficulties. So, this thesis presents a method for manufacturing system using Petri nets. Petri nets are a graphical and mathmatical modeling tool and are promising tool for describing and studying systems that are characterized as being concurrent asychronous, dynamic, distributed and parrallel. It designs Petri net model for processing time of manufacturing system And it applied to a job shop system composed of 8 machines and 4 different job types.

• 한국BIM학회 논문집
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• 제6권4호
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• pp.27-34
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• 2016

A Building Information Model (BIM) is an attempt to simulate the process of building structures in a three-dimensional (3D) digital space. While the technology is usually applied to structured buildings, bridges, and underground facilities, it is rarely applied to an unstructured environment of earthwork operations. If a BIM is used for earthworks, the 3D simulation can be used for construction equipment guidance and earthwork management. This paper presents a real-time, 3D earthwork BIM that provides a 3D graphical simulation of excavators in conjunction with geographic modeling. Developing a real-time, 3D earthwork BIM requires handling a variety of factors, such as geographical information and vehicular movement. This paper mainly focuses on the management of these attributes and provides a database design for storing and retrieving data. In an example application, a prototype of the 3D earthwork BIM is presented to understand what it would provide when used during earthwork operations at a construction site.

• International Journal of Aeronautical and Space Sciences
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• 제14권3호
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• pp.264-271
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• 2013

A method of multiple transport-aircraft mission modeling is proposed in order to improve the efficiency of evaluating and optimizing pre-mission plans. To deal with the challenge of multiple transport-aircraft missions, the object-oriented modeling method is utilized. The elements of the mission are decomposed into objects and businesses, And the major mission objects and their important properties are summarized. A complex mission can be broken down into basic business modules such as the ground section and flight section. The business models of loading and fueling services in the ground section are described. The business model of the flight section is composed of an air route and flight profile with the flight equation and the fuel consumption model. The logical relationship of objects and business modules is introduced. The architecture of the simulation system, which includes a database, computation module, graphical user interface (GUI) module, and a result analysis module, is established. A sample case that includes two different plans is provided to verify the model's ability to achieve multi-aircraft composite mission simulation.

• ETRI Journal
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• 제36권4호
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• pp.662-672
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• 2014

Human action recognition is used in areas such as surveillance, entertainment, and healthcare. This paper proposes a system to recognize both single and continuous human actions from monocular video sequences, based on 3D human modeling and cyclic hidden Markov models (CHMMs). First, for each frame in a monocular video sequence, the 3D coordinates of joints belonging to a human object, through actions of multiple cycles, are extracted using 3D human modeling techniques. The 3D coordinates are then converted into a set of geometrical relational features (GRFs) for dimensionality reduction and discrimination increase. For further dimensionality reduction, k-means clustering is applied to the GRFs to generate clustered feature vectors. These vectors are used to train CHMMs separately for different types of actions, based on the Baum-Welch re-estimation algorithm. For recognition of continuous actions that are concatenated from several distinct types of actions, a designed graphical model is used to systematically concatenate different separately trained CHMMs. The experimental results show the effective performance of our proposed system in both single and continuous action recognition problems.

• International Journal of Computer Science & Network Security
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• 제23권5호
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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.

• 한국정보통신학회논문지
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• 제22권7호
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• pp.978-984
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• 2018

구조방정식 모델링은 경로분석 및 확인적 요인분석을 동시에 수행해 주는 통계적 절차를 따르고 있다. 오늘날이 통계적 절차는 사회과학 분야의 연구자에게 필수적인 도구이다. 구조방정식 모델링 분석을 해주는 대표적인 도구로는 AMOS, LISREL 그리고 PLS가 있다. AMOS는 초보자가 사용할 수 있도록 편리한 그래픽 사용자 인터페이스를 제공해 주고 있다. PLS는 그래픽 사용자 인터페이스뿐만 아니라 정규분포에 대한 제약조건도 없다는 장점을 가지고 있다. 또한 사회과학 분야에서 가장 많이 사용하는 3가지 도구 (applications)를 비교분석 하였다. 구조방정식 모델링 기반 확인적 요인 분석은 IBM AMOS Ver 23, LISREL 8.70 및 SmartPLS 2.0을 사용하였다. 구조방정식 모델링 비교 분석 결과는 LISREL이 다른 분석 도구보다 종속 변수의 설명력이 가장 높음을 확인할 수 있었다. 분석 결과에 의해 제시된 경로계수 값 및 T 값은 3가지 분석 도구 모두 유사한 결과를 보이는 것으로 나타났다. 따라서 이러한 결과를 바탕으로 이론적 실무적 시사점을 제시하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.334-337
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• 1996

This is a paper intended for initial stage of vehicle modeling and design. The needs to determine a variety of vehicle suspension parameters required for initial design has been difficult and time-consuming task. In order to facilitate a concise and efficient presentation of initial vehicle design procedure, this paper uses a mathematical model and physical geometry. Vehicle model consists of dimensions, inertias and mechanical constants. These vehicle model parameters divided into several categories : basic parameters, coefficients and constants, design specification, spring and damper, bush stiffness, stabilizer bar, suspension geometry, tire, and vehicle weights of various design condition. This paper uses a vehicle design fundamental (VDF) program running under Windows 95 graphical interface. The features of VDF will be briefly outlined in this paper.

• 한국컴퓨터그래픽스학회논문지
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• 제2권1호
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• pp.61-67
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• 1996

3차원 컴퓨터 그래픽스 응용 프로그램은 그래픽 객체(graphical object)들의 관리와 디스플레이(display), 그리고 객체들에 발생하는 이벤트(event)등을 처리해야만 한다. 하지만, 이들은 상당히 복잡한 일일뿐만 아니라 많은 그래픽스 응용 프로그램에 공통되는 내용들이기 때문에, 이런 응용 프로그램들에게 유연성을 제공하는 툴을 개발하려는 시도가 계속되어져 왔다. 본 논문에서는 사용하기 편리하고 쉽게 모델링과 렌더링을 할 수 있는 기능을 제공하며, 객체 지향 기법으로 설계되었기 때문에 확장이 용이한 그래픽스 툴킷의 설계 및 구현에 대해 설명한다.

• 한국정밀공학회지
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• 제17권4호
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• pp.97-105
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• 2000

One of the most important steps to determine the blank shape and dimensions in deep drawing process is to calculate the surface area of the product. In general, the surface area of axisymmetric products is calculated by mathematical or graphical methods. However, in the case of non-axisymmetric products, it is difficult to calculate the exact surface area due to errors as separated components. Fortunately, it is possible for elliptical products to recognize the geometry of the product in the long side and short side by drafting in another two layers on AutoCAD software. So, in this study, a surface area calculating system is constructed for a design of blank shape of deep drawing products. This system consists of input geometry recognition module and three dimensional modeling module, respectively. The suitability of this system is verified by applying to a real deep drawing product. The system constructed in this study would be very useful to reduce lead time and cost for determining the blank shape and dimensions.

• Communications for Statistical Applications and Methods
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• 제23권5호
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• pp.363-383
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• 2016

The Weibull family of lifetime distributions play a fundamental role in reliability engineering and life testing problems. This paper investigates the potential usefulness of transmuted new generalized Weibull (TNGW) distribution for modeling lifetime data. This distribution is an important competitive model that contains twenty-three lifetime distributions as special cases. We can obtain the TNGW distribution using the quadratic rank transmutation map (QRTM) technique. We derive the analytical shapes of the density and hazard functions for graphical illustrations. In addition, we explore some mathematical properties of the TNGW model including expressions for the quantile function, moments, entropies, mean deviation, Bonferroni and Lorenz curves and the moments of order statistics. The method of maximum likelihood is used to estimate the model parameters. Finally the applicability of the TNGW model is presented using nicotine in cigarettes data for illustration.