• Journal of the Korean Institute of Intelligent Systems
• /
• v.22 no.4
• /
• pp.521-526
• /
• 2012

The performance of arrow from a manufacturing process depends on arrow's trajectory(archer's paradox) and intensity of an impact points. Especially, when conducting a shooting experiment over and over in the same experiment condition, the intensity of impact point is an objective standard to judge the performance of the arrow. However, the analysis method for the impact point is not enough, a previous research of the arrow's performance has been focused on a skill to optimize a manufacturing variables(feathers of an arrow, barb of an arrow, arrow's shaft, weight, external diameter, spine). In this paper, We propose measurement system of arrow's impact point with Mamdani fuzzy inference system and similarity of polygon for automation of impact point's measurement. Measuring the impact point data of the arrow moving with a high speed(approximately 275km/h) by using line laser and photo diode array, then the measured data are mapped to arrow's impact point with fuzzy inference and similarity of polygon.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.39 no.5
• /
• pp.43-50
• /
• 2002

To improve the current waveform of diode rectifiers, we propose a new operating principle for the voltage -doubler diode rectifiers. In the conventional voltage-doubler rectifier circuit, relatively large capacitors are used to boost the output voltage, while the proposed circuit uses smaller ones and a small reactor not to boost the output voltage but improve the input current waveform. A high input power factor of 97[%] and an efficiency of 98[%] are also obtained. The harmonic guide lines of proposed rectifier is no interfered with inverter switching, resulting in a simple, reliable and low-cost ac-to dc converters in comparison with the boost-type current-improving circuits.It compared conventional pulse-widthmodulated(PWM)inverter with half pulse-widthmodulated (HPWM) inverter. Proposed HPWM inverter eliminated dead-time by lowering switchingloss and holding over-shooting.

• The Journal of the Korea Contents Association
• /
• v.11 no.2
• /
• pp.152-161
• /
• 2011

The FPS, featured with high quality graphic of superior visual reality, is steadily growing because of the improvement of computer performance and technological advancement of game production. But most of the FPS games provide monotonous freedom with which players can only change the weapons in one character and this will make users lose their interests when playing games for long hours. Valve has introduced 'Team Fortress Classic' in 1999, in order to change the monotonous game methods. This game has attracted great attention because of the composition of various and unique characters through the introduction of military specialty system: that is the first trial in the history of FPS game. I, by analyzing this using MBTI, intend to analyze how much of immersion and interest the characters of various military specialties can provide to players when FPS games are developed.

• The Journal of Korean Institute for Practical Engineering Education
• /
• v.4 no.2
• /
• pp.38-45
• /
• 2012

Building a game has been used as effective and attractive way of teaching computer science. Building a usable Multi-player Game is requires important aspects of technology, teamwork and software engineering principles. The whole class was structured in to several teams and students needed to join one or two teams. Each team presented their progress, discussed future milestones and troubleshoots, updated documents for clearer communication and utilized SVN(Subversion) throughout the semester. Unlike usual class setting, all students worked collaboratively together like one company to achieve the goal. In one semester, students started from concept design and completed a working Multiplayer Online Game called "deBugger" (Fall 2009), and "World of Balance" (Fall 2011), while learning game design, 3D graphics, Game Engine, Server-client architecture, Game Protocol, network programming, database, Software Engineering principles, and large application development as a team project.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.9
• /
• pp.62-68
• /
• 2018

This study was conducted to improve the shooting stability of self propelled artillery by improving the flick rammer system. The flick rammer system is designed to reduce crew fatigue and shorten the movement and loading time of the shell compared with the conventional manual loading system. Basically, in the flick rammer system of the shooting type, fall-back occurs intermittently, which causes problems in the rapid loading. To solve this problem, a detailed C.A.E. (Computer Aided Engineering) analysis of the internal structure of the existing rapid loading field was conducted. Through this, we sought a solution that can prevent fall-back by reducing the flying distance. We then optimized the loading station to reduce the flying distance and confirmed the possibility of suppressing the fall-back compared to the existing product through actual tests in the field.

• Korean Journal of Applied Biomechanics
• /
• v.22 no.1
• /
• pp.17-24
• /
• 2012

This study is for providing fundamental data of sport biomechanics in GRF & plantar pressure of stepping foot of skilled & unskilled players' at the soccer instep shooting moments. Wearing Pedar-x of Novel, the study has drawn the following conclusion after measuring and analyzing the impact on the GRF and plantar pressure of stepping foot at the instep shooting moments. First, maximum vertical GRF showed higher in the skilled group than in the unskilled group. The results showed significantly different. This study reached the conclusion that the players in the skilled group performed faster and stronger stepping foot motions that the ones in the unskilled(p<.01). Second, since the plantar pressure of the skilled group appeared significantly higher than that of the unskilled, it has brought us to the conclusion that the skilled group performed faster and stronger stepping foot motions than the unskilled group (p<.05). Third, at the moment of instep kicking, the skilled group's average maximum plantar foot pressure of stepping foot was higher than the unskilled. Though the difference was not statistically significant, it can be concluded that the skilled group performed faster and stronger stepping foot motions than the unskilled group(p>.05). Fourth, for the COP moving route of stepping foot while instep kicking, the skilled people performed accurate and strong shooting motions directly toward the target direction with stable postures, no matter how it's left, right, front or back.

• The Journal of the Korea Contents Association
• /
• v.15 no.11
• /
• pp.215-226
• /
• 2015

As violent video game is used based on active interaction and involvement of users, it is widely thought that it may have more effect on individual violence and aggressive action than existing violent videos. This study aimed to examine the effect of user experiences in the violent video game such as hostility, anger, arousal, enjoyment and identification on users' aggressive action. For this purpose, the first person FPS shooting game that consists of violent contents was employed to carry out playtest for 80 subjects with 40 male and 40 female university students. As a result, it was found that the user's arousal level, state anger, enjoyment and identification experience by the use of violent video game had an effect on aggressive action. Among factors that have aggressive action in the used of violent video game, besides emotion and arousal, the level of identification with a game character was found to be important effect factor. Hostility factor that was assumed to have effect on aggressive action was not significant, but enjoyment of game was proved to have effect on aggressive action of users.

• Journal of Korea Game Society
• /
• v.10 no.1
• /
• pp.15-23
• /
• 2010

In action games such as shooting games or platform games, dodging enemy objects is crucial since the player character dies or loses energy when it collides with any enemy object. In this paper, we investigates how the difficulty of these games changes according to the existence of salient objects. Since salient objects attract the player's attention, other non-salient objects may be unattended by the player, resulting in failing to dodge them. We experimented on the influence of salient objects on the difficulty of a game, and found out that the subjects who played the game without salient objects performed better than the subjects who played the game with salient objects. This paper investigates a human perceptual issue that could affect the game difficulty and suggest a potential guideline for game design and planning.

• Journal of the Korea Society of Computer and Information
• /
• v.17 no.4
• /
• pp.109-119
• /
• 2012

As it is developing and growing up the mobile telecommunication, commercial mobile, and the application on it, the smart phone is attracting public attention techniques, hereafter. In this paper, we can make the context-awareness platform to supply users with the interface for their appropriate contexts using the smart phone. Therefore, we use the sensors in the smart phone, and the values from them are analyzed. As a result, we can estimate the user's contexts, such as the sitting and standing, movement, the lights, positions, locations, etc. In addition, we happen the suitable events from them for users. Therefore, we can provide the perspective interfaces for them. In addition, to prove the more efficiency of the proposed platform, we implemented the shooting game, and could know that the performance is the more advanced than the others. The proposed algorithm can be used for the mobile environments, which high efficiency is required such as the game, or the implementation of mobile applications which are more efficient to the user interfaces, etc.

• Korean Journal of Applied Biomechanics
• /
• v.16 no.2
• /
• pp.153-163
• /
• 2006

The purpose of this research was to analyze kinematic variables that appear during the instep shooting motion of female high school soccer players according to the angle of approach to find effective shooting motions. For this experiment, 5 female high school soccer players from the K city were participated in this study as the subject group, and as a through comparison and analysis of the resulting numbers of the variables, we came to the following conclusions. 1) Stride length and stride length/lower extremity length increased as the angle of approach increased. 2) As for C.O.G movement displacement, it was highest at an approach angle of $90^{\circ}$ during Right Foot Contact, at $135^{\circ}$ during Left Foot Contact, at $0^{\circ}$ during Rigth Toe Top, at $45^{\circ}$ during Impact, and at $0^{\circ}$ during Follow through. 3) The time required for each phase was longest at APP and shortest at BSP. The time required increased a little as the angle of approach increased, and the total time required also increased as the angle of approach increased. 4) The angle of the ankle joint was largest at an approach angle of $45^{\circ}$ for all events except Right Foot Contact. 5) The angle of the knee joint was largest at an approach angle of $135^{\circ}$ during Right Foot Contact, at $0^{\circ}$ during Left Foot Contact, at $45^{\circ}$ during Right Toe Top, at $135^{\circ}$ during Impact, and at $90^{\circ}$ during Follow through. 6) The angle of the hip joint was largest at an approach angle of $90^{\circ}$ during Right Foot Contact, at$0^{\circ}$ during Left Foot Contact, at $0^{\circ}$ during Right Toe Top, at $90^{\circ}$ during Impact, and at $0^{\circ}$ during Follow through.