• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.38 no.5
• /
• pp.490-498
• /
• 2010

This paper presents an autonomous target tracking approach and technique for transmitting ground control station image periodically for an unmanned aerial vehicle using onboard gimbaled(pan-tilt) camera system. The miniature rotary UAV which was used in this study has a small, high-performance camera, improved target acquisition technique, and autonomous target tracking algorithm. Also in order to stabilize real-time image sequences, image stabilization algorithm was adopted. Finally the target tracking performance was verified through a real flight test.

• Journal of Astronomy and Space Sciences
• /
• v.28 no.4
• /
• pp.345-354
• /
• 2011

Earth acquisition is to solve when earth can be visible from satellite after Sun acquisition during launch and early operation period or on-station satellite anomaly. In this paper, the algorithm and test result of the Communication, Ocean and Meteorological Satellite (COMS) Earth acquisition are presented in case of on-station satellite anomaly status. The algorithms for the calculation of Earth-pointing attitude control parameters including those attitude direction vector, rotation matrix, and maneuver time and duration are based on COMS configuration (Eurostar 3000 bus). The coordinate system uses the reference initial frame. The constraint calculating available time-slot to perform the earth acquisition considers eclipse, angular separation, solar local time, and infra-red earth sensor blinding conditions. The results of Electronics and Telecommunications Research Institute (ETRI) are compared with that of the Astrium software to validate the implemented ETRI software.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.2
• /
• pp.866-871
• /
• 2012

Most of the computer to implement a Augmented reality 3-D, or a graphic or visual means through the virtual space. The participants in the Augmented reality immersive virtual reality and virtual reality, the process proceeds to change the world. In particular, the field of children's games and Augmented reality fits well with the technical characteristics of the children that may lead to more interesting and creative sector is pointing to. In this study, children's games in order to maximize learning effectiveness of board games and Augmented reality technology, take a look at the characteristics of the children's educational program is to propose a new model proposal.

• English Language & Literature Teaching
• /
• v.13 no.1
• /
• pp.133-158
• /
• 2007

The purpose of this study is to try to date the letters of Lady Susan and to find out which year's calender Jane Austen used to write the novel. The novel in forty-one letters with a brief narrated conclusion was transcribed as a fair copy by Jane Austen around 1805. However, no conclusive evidence for a precise date of composition exists, as only the fair copy survives. There is a watermark of 1805 on two leaves of the surviving manuscript of the transcribed copy. This indicates the period of the work's transcription but it does not indicate when it was first composed beyond suggesting that it was completed sometime before 1805. In the novel itself Jane Austen marked time sufficiently and frequently enough to allow us to follow it precisely. This strongly suggests that Jane Austen used a calender to write letters of the novel, even though dates and days were not given to the letters. To determine the most probable date of the calender is significant because it can be a clue to clarify when the novel was composed originally. Many words and phrases pointing to specific days or periods are mentioned in almost all the letters of the novel. From the words and phrases, a potential date to each letter can be successfully deduced and a potential possible calender for the novel can be made. In the end, all attempts to determine the authentic calender used for the novel fail. The main reason for the failure is that discovering clues to a specific authentic date to each letter proves internally impossible. Composition date of the novel still remains as a challenge requiring further study.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.202-205
• /
• 2004

This paper represents the role of pinna in localizing target direction. Specially, this paper described what is the role of right-side pinna versus left-side pinna. In this experiment, one side of the pinna function was distorted intentionally by inserting a short tube on the ear canal. The localization error caused by right and left side pinna distortion was investigated. Since a laser pointer showed much less error (0.5%) in localizing target position than FASTRAK (30%) that has been generally used, it was used for the pointing task. It was found that harmonic components were not essential for the auditory target localization, however, non-harmonic nearby frequency components were more important to localize target direction of sound. We have found that the right pinna is one of the most important functions in localizing target direction and pure tone with only one frequency component is confusing for localization.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.1126-1129
• /
• 2003

In this paper, we propose a multi-agent system for assisting those who need help in taking objects around him/her. One may imagine this kind of situation when a person is lying in bed and wishes to take an object on a distant table that cannot be reached only by stretching his/her hand. The proposed multi-agent system is composed of three main independent agents; a vision agent, a robot agent, and a pass agent. Once a human expresses his/her intention by pointing to a particular object using his/her hand and a finger, these agents cooperatively bring the object to him/her. Natural communication between a human and the multi-agent system is realized in this way. Performance of the proposed system is demonstrated in an experiment, in which a human intends to take one of the four objects on the floor and the three agents successfully cooperate to find out the object and to bring it to the human.

• BMB Reports
• /
• v.50 no.11
• /
• pp.539-545
• /
• 2017

The Integrated Stress Response (ISR) refers to a signaling pathway initiated by stress-activated $eIF2{\alpha}$ kinases. Once activated, the pathway causes attenuation of global mRNA translation while also paradoxically inducing stress response gene expression. A detailed analysis of this pathway has helped us better understand how stressed cells coordinate gene expression at translational and transcriptional levels. The translational attenuation associated with this pathway has been largely attributed to the phosphorylation of the translational initiation factor $eIF2{\alpha}$. However, independent studies are now pointing to a second translational regulation step involving a downstream ISR target, 4E-BP, in the inhibition of eIF4E and specifically cap-dependent translation. The activation of 4E-BP is consistent with previous reports implicating the roles of 4E-BP resistant, Internal Ribosome Entry Site (IRES) dependent translation in ISR active cells. In this review, we provide an overview of the translation inhibition mechanisms engaged by the ISR and how they impact the translation of stress response genes.

• Advances in aircraft and spacecraft science
• /
• v.5 no.4
• /
• pp.459-475
• /
• 2018

In the field of aerospace engineering, accurate control of a spacecraft's orientation is often very important to mission success. Therefore, attitude control is a technically plentiful and extensively studied subject in controls literature during recent decades. This investigation of spacecraft attitude control is assumed to address two important aspects of the problem solutions. One sliding mode anti-disturbance control for utilization of faulty actuator components and another one disturbance observer based control to improve the pointing accuracy in the absence of anti-vibration equipment for the elastic appendages like a solar panel. Simultaneous occurrence of vibration due to flexible appendages and reaction degradation due to failure in attitude actuators complicates this case. The advantage of this method is acquisition proper control by the combination of disturbance observer and sliding mode compensation that form a fault tolerant control for the concerned satellite attitude control system. Furthermore, the proposed composite method indicates that occurrence the failure in actuators and even elastic solar panel vibration effect may be handled directly without reconfiguring the control components or providing piezoelectric devices. It's noteworthy, attitude quaternion and angular velocity commands are robustly tracked via controllers to become inclined to zero.

• Journal of Astronomy and Space Sciences
• /
• v.32 no.4
• /
• pp.281-287
• /
• 2015

Two mini neutron monitors are installed at Concordia research station (Dome C, Central Antarctica, $75^{\circ}06^{\prime}S$, $123^{\circ}23^{\prime}E$, 3,233 m.a.s.l.). The site has unique properties ideal for cosmic ray measurements, especially for the detection of solar energetic particles: very low cutoff rigidity < 0.01 GV, high elevation and poleward asymptotic acceptance cones pointing to geographical latitudes > $75^{\circ}S$. The instruments consist of a standard neutron monitor and a "bare" (lead-free) neutron monitor. The instrument operation started in mid-January 2015. The barometric correction coefficients were computed for the period from 1 February to 31 July 2015. Several interesting events, including two notable Forbush decreases on 17 March 2015 and 22 June 2015, and a solar particle event of 29 October 2015 were registered. The data sets are available at cosmicrays.oulu.fi and nmdb.eu.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.55 no.4
• /
• pp.165-172
• /
• 2006

In this paper we present a technique for detecting cross-reference points that allows improving watermark detect-ability. In general, Harris detector is commonly used for finding salient points. Harris detector is a kind of combined corner and edge detector which is based on neighboring image data distribution, therefore it has some limitation to find accurate salient points after watermark embedding or any kinds of digital attacks. The new method proposed in this paper used not data distribution but geometrical structure of a normalized image in order to avoid pointing error caused by the distortion of image data. After normalization, we constructed pre-specified number of virtual lines from top to bottom and left to right, and several of cross points were selected by a random key. These selected points specify almost same positions with the accuracy more than that of Harris detector after digital attacks. These points were arranged by a random key, and blocks centered in these points were formed. A reference watermark is formed by a block and embedded in the next block. Because same alteration is applied to the watermark generated and embedded blocks. the detect-ability of watermark is improved even after digital attacks.