• Journal of Korea Multimedia Society
• /
• v.10 no.8
• /
• pp.1060-1067
• /
• 2007

We need various methods to develop MMORPG that is game genre which many users use among various game genre using Internet. Specially, to heighten efficiency of distributing work, Object-oriented language such as C++ is used and we need design techniques that can take advantage of enough object-oriented concept when making large-scale game. There is various pattern that can apply in software breakup design in GoF's design pattern for these design techniques. If you apply Observer pattern to Party System Design for forming community between game users, you can easily add new class and maintain system later. Party Play is one of the important system that is used to form game users' community in MMORPG games. The main point that must be considered in Party-Play-System is to divide evenly experience value and acquisition that is got by Party-Play among users according to each user's level. To implement Party Play System that consider maintenance of system, in this paper, we propose a method using GoF's Observer-Pattern, showing you that proposed method which has advantage to dynamic memory allocation and to virtual method call can be used usefully to change object to real time at program run and to add new class and to maintain system new.

• 제어로봇시스템학회:학술대회논문집
• /
• 1990.10a
• /
• pp.101-106
• /
• 1990

The problem of constructing an observer for use in the control of superheater temperature with desuperheater is considered. The distributed heat input into the superheater is usually not available for use in the observer, and hence is treated as a disturbance. The observer theory for systems with unknown inputs is exploited and applied to the problem. Approximation of the heat input utilizing the specific heat input distribution pattern is also considered.

• Journal of Internet Computing and Services
• /
• v.7 no.2
• /
• pp.81-92
• /
• 2006

Recently, the number of mobile phone and PDA users has been rapidly increased. Such monitoring and control applications as geographical and traffic information systems are being used widely with wireless devices. In this paper, we introduce the mobile M/VC application framework that supports the rapid constructions of mobile monitoring and control (M/VC) applications. The mobile M/VC application framework uses the mobile Observer/Observable pattern that extends the Java's Observer/Observable for automatic interactions of server and client objects in wireless environments. It also provides the Multiplexer and Demultiplexer classes that supports the assembly feature of Observer and Observable objects. To construct an application using the framework, developers just need to create necessary objects from the Observable and MobileObserver classes and inter-connect them structurally(like the plug-and-play style) through the Multiplexer and Demultiplexer objects. Then, the state change of Observable objects is notified to the connected Observer objects and user's input with Observer objects is propagated to Observable objects. These mechanism is the main process for monitoring and control applications. Therefore, the mobile M/VC application framework can improve the productivity of mobile applications and enhance the reusability of such components as Observer and Observable objects in wireless environments.

• International Journal of Aeronautical and Space Sciences
• /
• v.14 no.4
• /
• pp.379-386
• /
• 2013

The hemispherical resonator gyroscope is a type of vibratory gyroscope, which can measure angle or angular rate, based on its operating mode. This paper deals with the case when the hemispherical resonator gyroscope is operated in angle measurement mode. In angle measurement mode, the resonator pattern angle precesses, with respect to the external rotation input, by the principle of the Coriolis effect, so that the external rotation can be estimated, by measuring the amount of precession angle. However, this pattern angle drifts, due to the manufacturing error of the resonator. Since the drift effect causes degradation of the angle estimation performance of the resonator, the corresponding drift compensation control should be performed, to enhance the estimation performance. In this paper, a mathematical model of the hemispherical resonator gyro is first introduced. By using the mathematical model, a nonlinear observer for imperfection parameter estimation, and the corresponding compensation controller are designed to operate hemispherical resonator gyros, as angle measurement sensors.

• Journal of Information Technology Services
• /
• v.12 no.3
• /
• pp.421-432
• /
• 2013

The changes in the game platform is appeared since the advent of smart-phones. Apple's iOS or Google's Android platform is gradually expanding their territories in the mobile game area. Android's platform fragmentation and the absence of game development framework act as barriers for game developments. In the development of game applications on the smart-phone, the standardized development procedures under game framework can achieve the productivity improvement. In this paper, we propose a new design pattern suitable for the design of a framework for new areas of application through the expansion of existing framework. The design and implementation of the Android game development framework is presented by taking advantage of existing design patterns and a proposed pattern. Also we propose the standardized development procedure of game applications under the proposed framework.

• Journal of Korea Multimedia Society
• /
• v.19 no.8
• /
• pp.1544-1552
• /
• 2016

If the undo/redo function is not reflected in the initial design of an application, it makes it difficult to implement the undo/redo function additionally, in this paper, we examined some examples to design the sodoku game and analyzed problems of the design to implement the undo/redo functions. For an efficient design of the undo/redo functions without using swing.undo package, we propose a class design using the Command, Memento, and Observer pattern these are used as organic. The proposed method is more efficient for distributed work than other method. We implemented a sudoku game using proposed design. In the undo/redo function testing, we could see that it works well.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2009.11a
• /
• pp.217-218
• /
• 2009

URC 로봇은 고성능 서버를 통해 로봇이 수행할 서비스의 일부를 외부 디바이스에 분담시킴으로써 저렴한 하드웨어로 로봇을 구현하고자 하는 목적을 가지는 지능형 서비스 로봇이다. SOMAR는 유비쿼터스 환경에서 사용자에게 다양한 원격 로봇 서비스를 제공하기 위한 URC 로봇 미들웨어로, URC 로봇 클라이언트와 이를 등록, 제어, 관리하는 서버로 구성된다. SOMAR 서버를 통해 로봇 서비스를 수행하기 위해서는 로봇 클라이언트의 상태정보를 모니터링하여 수행가능 여부를 판단해야 한다. 본 논문은 이러한 상태정보 모니터링을 위해 R-OSGi를 이용한 분산 Observer 패턴을 구현한다. Observer 패턴은 객체간에 느슨한 결합구조를 가져 URC 로봇 클라이언트 모니터링 프로그램의 개발과 수정이 용이하고, 플러그인 방식의 개발을 통해 다양한 프로그램 설치와 응용이 가능하다.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.1
• /
• pp.251-260
• /
• 2015

The main purpose of this paper is to describe a DTC (direct torque control) method for four-switch brushless dc motor (BLDCM) drive. In the method, a novel voltage space vector modulation scheme, an optimal switching table, and a flux observation method are proposed. Eight voltage vectors are summarized, which are selected to control BLDCM in SVPWM pattern, and an optimal switching table is proposed to improve the torque distortion caused by midpoint current of the split capacitors. Unlike conventional flux observers, this observer does not require speed adaptation and is not susceptible to speed estimation errors, especially, at low speed. Global asymptotic stability of the flux observer is guaranteed by the Lyapunov stability analysis. DC-offset effects are mitigated by introducing a PI component in the observer gains. This method alleviates the undesired current and torque distortion which is caused by uncontrollable phase. The correctness and feasibility of the method are proved by simulation and experimental results.

• Journal of the Korean Society of Radiology
• /
• v.9 no.7
• /
• pp.515-521
• /
• 2015

This study assessed the degradation of image quality caused by grid artifacts and $moir{\acute{e}}$ pattern artifacts in a stationary grid, and the degradation of image quality caused by cut off artifacts in a moving grid. X-ray images were acquired in a stationary grid and a moving grid with X-ray exposure conditions of 100 cm, 80 kVp, and 30 mA using a CDRAD phantom and a 24 cm thickness acrylic phantom. Observer's perception of X-ray imaging using CDRAD Analyzer was mean 49.36, standard deviation 3.76, maximum 55.56, and minimum 38.67 in the stationary grid, and 47.04, 12.69, 55.56, and 20.89, respectively, in the moving grid. The stationary grid was superior to the moving grid in terms of the mean and standard deviation of observer's perception.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.1
• /
• pp.89-97
• /
• 2017

Recent Internet of Things(IoT), and in addition to wearable PC, such as software development methodologies based on a variety of object-oriented design and design patterns of GoF(Gang of Four) with OOP(Object-Oriented Programming) intended for portable devices. However, incorrect application design specification is that the higher the importance of the optimization of the program on the device because it can cause problems such as decreased operating speed, increase the memory occupancy and battery usage. In this paper, we propose an optimized design pattern based on the method of application, such as Android (Android) OS Strategy Pattern, State Pattern, Observer pattern. Test results show that the proposed scheme selection patterns can be selected to optimize the design pattern in the device that specification.