• 한국동물학회지
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• 제38권2호
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• pp.230-237
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• 1995

Playback experiments were excecuted with seven threat Tit males inhabited in Gsngnae Myeon, Darak Ri, Chungbuk province to investigate the signal value of partial song (one unit phrase composed of two notes) as a species recognition releaser. Territorial males responded strongly to their own natural, synthetic and partial songs played in the field. However, thew showed weak or no responses to the playback songs of other species: Coal Tit (Porus ate4 and Yellow-throated Bunting (EmberiEa elegansl.6reat Tits distinguished conspecific partial songs readily from songs of other species. The results demonstrated that one unit phrase which is a basic arrangement of the Great Tit song, containes information on species recognition.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅳ
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• pp.2116-2119
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• 2003

In this paper, we present a DirectShow-based retrieval and playback subsystem of DVR(Digital Video Recorder), which supports real-time playback of stored video data and synchronized playback among several video channel data. The effectiveness of out proposed design is verified through experiments with a DVR system implementing the proposed design.

• Animal cells and systems
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• 제3권2호
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• pp.149-151
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• 1999

It has been suggested that the bush warbler (Cettia diphone borealis) uses different song types in various situations. We analyzed song features and conducted playback experiments in order to reveal the function of songs of the bush warbler. Two song types were identified. The short song type has a shorter song duration than that of normal song types and consists of only one or two syllables. Due to its short syllable and low amplitude of the whistle portion, we were able to discriminate the short song type (S song type). from the normal song type (N song Type). In the playback experiments, bush warblers sang high rates of short song type for the first three minutes after playback. After 6 minutes of playback, males changed to singing normal songs. These results suggest that the short song of the bush warbler may function to threaten or drive off intruding males.

• 한국동물학회지
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• 제38권4호
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• pp.443-448
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• 1995

충북 청원군 일대에서 휘파람새 6 개체에 대하여 군집내 인 청원군집의 song과 군집외 인 제주개체의 song을 이용하여 playback실험을 실시하였다. 실험의 대상개체는 모두 다두 군집의 song에 대하여 강한 반응을 보였으나 군집 사이에 대하여 통계적으로 의미 있는 차이를 나타내지는 않았다. 이러한 결과는 청원군집내의 개체간의 먼 간격으로 인하여 이웃 개체간의 적은 상호작용에서 기인되어지는 것으로 판단된다. Song의 부분들이 song의 인식에 기여하는 정도를 파악하기 위하여, 휘파람새 song의 whistle 부분과 complex syllsble 부분을 이용하여 playback실험을 실시하였다. Complex syllable 부분에 대한 반응의 정도가 whistle 부분에 비하여 의미 있게 높았으며, 이러한 것은 song의 특정한 부분이, complex syllable, 개체의 song인식에 필요한 주된 정보를 담고 있다는 'releaser '가설을 지지하는 결과로 나타났다.

• Journal of Astronomy and Space Sciences
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• 제27권2호
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• pp.107-116
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• 2010

We developed the playback control software for a high-speed playback system which is a component of the Korea-Japan Joint VLBI Correlator (KJJVC). The Mark5B system, which is a recorder and playback system used in the Korean VLBI Network (KVN), has two kinds of operation mode. That is to say, the station unit (SU) mode, which is for the present Mark4 system, and the VSI mode, which is for the new VLBI standard interface (VSI) system. The software for SU is already developed and widely used in the Mark4 type VLBI system, but the software for VSI has only been developed for recording. The new VLBI system is designed with a VSI interface for compatibility between different systems. Therefore, the playback control software development of the VSI mode is needed for KVN. In this work, we developed the playback control software of the Mark5B VSI mode. The developed playback control software consists of an application part for data playing back, a data input/output part for the VSI board, a module for the StreamStor RAID board, and a user interface part, including an observation time control part. To verify the performance of developed playback control software, the playback and correlation experiments were performed using the real observation data in Mark5B system and KJJVC. To check the observation time control, the data playback experiment was performed between the Mark5B and Raw VLBI Data Buffer (RVDB) systems. Through the experimental results, we confirmed the performance of developed playback control software in the Mark5B VSI mode.

• 제어로봇시스템학회논문지
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• 제15권5호
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• pp.538-542
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• 2009

Industrial manipulators have been mostly used in large companies such as automakers and electronics companies. In recent years, however, demands for industrial manipulators from small and medium-sized enterprises are on the increase because of shortage of manpower and high wages. Since these companies cannot hire robot engineers for operation and programming of a robot, intuitive teaching and playback techniques of a robot manipulator should replace the robot programming which requires substantial knowledge of a robot. This paper proposes an intuitive teaching and playback algorithm used in assembly tasks. An operator can directly teach the robot by grasping the end-effector and moving it to the desired point in the teaching phase. The 6 axis force/torque sensor attached to the manipulator end-effector is used to sense the human intention in teaching the robot. After this teaching phase, a robot can track the target position or trajectory accurately in the playback phase. When the robot contacts the environment during the teaching and playback phases, impedance control is conducted to make the contact task stable. Peg-in-hole experiments are selected to validate the proposed algorithm since this task can describe the important features of various assembly tasks which require both accurate position and force control. It is shown that the proposed teaching and playback algorithm provides high positioning accuracy and stable contact tasks.

• Animal cells and systems
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• 제9권4호
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• pp.199-203
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• 2005

We studied the effectiveness of mating call playbacks on call monitoring of three-striped pond frogs (Rana nigromaculata). Playback experiments were conducted between 2100 to 0030 at 15 sites located at Chungwon, Chungbuk, and Yeongi, Chungnam, in May 2005. We recorded call responses of 25 males to two different call playbacks, (i) single mating calls from a single male and (ii) chorus mating calls from five males, by randomly presenting the calls with a 15 min-gap between the two playbacks. We compared the number of response calls of the focal males for three min before, during, and after the playbacks. Five of 25 males were silent before stimulus presentation, but all the males emitted calls after the playbacks. The number of calls in response to single playback calls significantly differed among the three playback periods, where males gave more calls during the playback than before or after the playbacks. In addition, subject males presented significantly more calls to single call playbacks than to chorus call playbacks. The results of this study suggest that playback using repeated single mating calls is effective in call monitoring of R. nigromaculata males.

• 정보처리학회논문지B
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• 제17B권6호
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• pp.413-420
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• 2010

분산 모바일 멀티미디어 시스템에서 클라이언트의 재생 버퍼 수준에 기반하여 통신망 대역폭을 동적으로 할당하는 기법이 본 논문에서 제시된다. 이 기법에서 비디오 요청을 서비스하기 위해 할당된 대역폭의 양은 요구한 클라이언트의 버퍼 수준에 따라 결정된다. 즉 클라이언트의 버퍼 수준이 일시적으로 낮아지거나 높아지면 재생 상황을 개선하기 위한 목적으로 더 많은 대역폭 또는 더 적은 대역폭이 할당되는 것이다. 또한 재생 버퍼 수준 기반 대역폭 할당 기법을 사용함으로써 클라이언트들에게 공평한 서비스가 제공될 수 있다. 고품질의 비디오 재생을 지원하기 위해서 비디오 프레임들은 반드시 재생 시간 전까지 클라이언트에 전송되어야 한다. 이 대역폭 할당 기법의 주목적은 전송이 중단되는 프레임의 수를 최소화하여 비디오 재생 성능과 서비스 품질을 향상시키며 동시에 진행되는 모든 비디오 요청 작업을 공평하게 서비스하는 것이다. 제시된 기법의 성능은 시뮬레이션을 통하여 다른 정적 대역폭 할당 기법과 비교 분석되었으며 프레임의 전송중단율은 버퍼수준에 따라 약 4%에서 9% 정도 감소된 것으로 나타났다.

• 전기전자학회논문지
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• 제28권2호
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• pp.145-149
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• 2024

최근 시간적 행동 검출 연구가 활발히 진행되고 있다. 시간적 행동 검출 연구의 한 분야인 오프라인 행동 검출은 온라인 행동 검출과 달리 비디오를 한번에 입력으로 받는다. 이를 통해 오프라인 행동 검출은 양방향 정보를 이용할 수 있으며 또한 이를 학습하기 위해 Bi-directional LSTM을 주로 사용한다. 본 논문에서는 기존 방법과 달리 완전지도 시간적 행동 검출에서 역재생 비디오를 생성하고 이를 통해 양뱡향 정보를 학습하는 방법을 제안한다. 구체적으로 역재생 비디오와 순재생 비디오를 함께 학습 데이터로 구성하는 방법과 각각 모델에 학습시킨 후 두 모델을 앙상블 모델로 구성하는 방법을 제안하였다. 제안하는 방법의 성능 평가를 위해 TALLFormer 모델을 이용하여 THUMOS-14 데이터셋에 대한 실험을 진행하였다. 역재생 및 순재생 비디오를 학습 데이터로 구성한 경우 기존 방법에 비해 5.1% 낮은 성능을, 모델 앙상블을 진행했을 경우 1.9% 우수한 성능을 보였다.

• 천문학논총
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• 제23권2호
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• pp.91-107
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• 2008

In this paper, we introduce the performance evaluation and development of Raw VLBI Data Buffer(RVDB) system for the synchronized playback processing of observed data in Korea-Japan Joint VLBI Correlator(KJJVC). The high-speed correlation processing system is under development so that the radio data obtained with 8192 channels and 8 Gbps speed from 16 stations will be able to be processed. When the recorded data of each station are played to correlator, the time synchronization of each station is very important because the correlator should process the data obtained with same time and condition. There are many types of recorder systems in the East Asia VLBI Network (EAVN). Therefore it is required to prepare the special time synchronized playback processing system to synchronize the time tag of observed data. The developed RVDB system consists of Data Input Output(DIO), 10GbE switch, and Disk Data Buffer(DDB). It can record the data with maximum 2 Gbps speed, and can play back the data to correlator with nominal 2 Gbps speed. To enable to play back the data of different playback system to the correlator, we developed the high-speed time synchronized playback processing system. We carried out the experiments of playing back and correlation for gigabit correlator and VCS trial product so as to confirm the performance of developed time synchronized playback processing system. In case of online and offline playing back experiment for gigabit correlator, we confirmed that the online and offline correlation results were the same. In case of playing back experiment for VCS trial product, we verified that the wide band and narrow band correlation results were also the same. Through the playing back experiments of RVDB system, the effectiveness of developed RVDB system was verified. In this paper, the system design, construction and experimental results are shown briefly.