• The KIPS Transactions:PartB
• /
• v.17B no.6
• /
• pp.413-420
• /
• 2010

In this paper, we propose a scheme for dynamic allocating network bandwidth based on the playback buffer levels of the clients in a distributed mobile multimedia system. In this scheme, the amount of bandwidth allocated to serve a video request depends on the buffer level of the requesting client. If the buffer level of a client is low or high temporarily, more or less bandwidth will be allocated to serve it with an objective to make it more adaptive to the playback situation of this client. By employing the playback buffer level based bandwidth allocation policy, fair services can also be provided to the clients. In order to support high quality video playbacks, video frames must be transported to the client prior to their playback times. The main objectives in this bandwidth allocation scheme are to enhance the quality of service and performance of individual video playback such as to minimize the number of dropped video frames and at the same time to provide fair services to all the concurrent video requests. The performance of the proposed scheme is compared with that of other static bandwidth allocation scheme through extensive simulation experiments, resulting in the 4-9% lower ratio of frames dropped according to the buffer level.

• The Journal of the Korea Contents Association
• /
• v.17 no.4
• /
• pp.532-540
• /
• 2017

This study analyzes and compares the meaning and the value of storytelling with characteristics of the Playback Theatre, which is an improvisational play. On one side, the Playback Theatre, invented by Jonathan Fox in 1975, is an improvisational and communication-based theatre format; and it usually brings in the storytelling of audiences and often entails no play script. On the other side, storytelling requires imagination and creativity; presupposes the sympathy between the speaker and the listener. In fact, this theatre format is utilizing the educational and healing effects of verbal cultures, group sacrificial ceremonies, and/or psychodrama; and it is contextualizing them in our modern society. The Playback Theatre provides the audiences with opportunities to share their own stories within the play itself. The actors first listen to the stories of audiences; and then make them into a play impromptu, right in front of the speaker(s) and other audiences. For this very reason, it is called a "play-back". In this process, the individuals and the community are invited to experience the educational and healing effects.

• The Korean Journal of Zoology
• /
• v.38 no.4
• /
• pp.443-448
• /
• 1995

Playback experiments were performed to clarify the degree of song recognition using inter - and intra-populatlon songs of Bush Warbler at Cheongwon, Chungbuk area. Six territorial males were strongly responded to inter- as well as intrapopulation songs. Their responses to the inter- and Intra-population songs were not differed significantly in all measures of latency time, staying time, and closest distance. This result imply that Bush Warbiers in the region did not discriminate the difference between intra- and inter-population songs. It may be the reason that the regional males have little Interactions In song exchange with neighbors by keeping a long Individual distance. In order to investigate the signal value as species recognition releaser, playback of partial songs, prepared from tow distinct regional populations of the spedes were presented to males of the study area. The partial songs presented were made of two portions for each presentation, a whlsde portion only, and a complex syllable portion only. Territorial males responded stronger to the complex syllable portion than the whistle portion of the song. This result indicate that the complex syllable portion conveys more information on the species recognition. As 'releaser' hypothesis suggested formerly, a function of the complex syllable portion In Bush Warbler song is understood In which conveys most spedesIdentifying information. Thus, the result of this playback experiments supports the releaser hypothesis.

• Journal of the Institute of Convergence Signal Processing
• /
• v.21 no.2
• /
• pp.67-72
• /
• 2020

AR service using the client-server method and existing physical markers(eg, OR Codes, etc.) causes a delay in the playback time of the contents because the contents download is executed after the marker recognition. In the case of the one-time installation method rather than the client-server method, proactive download of high-capacity contents for playback may cause an inefficiency of the storage space of the device(eg, smartphone, etc.). Therefore, in AR contents playback based on beacon's RSSI to secure the efficiency of the playback device storage space and to quickly play AR contents. The technique for high-speed playback in this study can be applied to various fields such as MICE exhibition using beacon signal.

• Journal of IKEEE
• /
• v.28 no.2
• /
• pp.145-149
• /
• 2024

Recently, research on temporal action localization has been actively conducted. In this paper, unlike existing methods, we propose two approaches for learning bidirectional information by creating reverse playback videos for fully supervised temporal action localization. One approach involves creating training data by combining reverse playback videos and forward playback videos, while the other approach involves training separate models on videos with different playback directions. Experiments were conducted on the THUMOS-14 dataset using TALLFormer. When using both reverse and forward playback videos as training data, the performance was 5.1% lower than that of the existing method. On the other hand, using a model ensemble shows a 1.9% improvement in performance.

• Animal cells and systems
• /
• v.9 no.4
• /
• pp.199-203
• /
• 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.

• 전기의세계
• /
• v.29 no.7
• /
• pp.460-470
• /
• 1980

The design of a control unit for a playback-type industrial robot is studied. Implemented for the cylindrical-coordinate type industrial robot with 5 degrees of freedom, the control unit constructed for the study consists of (i) z-80 .mu.p-based .mu.-computer control system (ii) Teach-Box for work command, and (iii) various softwares for generating signals for servo driving unit and operating the robot as playback-type. Softwares are developed by using high level Basic Language and low level z-80 Assembly Language for ease of programming and speed of program execution. To show the effectiveness, and example is included.

• Animal cells and systems
• /
• v.3 no.2
• /
• pp.149-151
• /
• 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.

• The Korean Journal of Ecology
• /
• v.25 no.1
• /
• pp.25-28
• /
• 2002

The advertisement call of anurans functions to attract potential mates. The dominant frequency of an advertisement call is generally getting lower with increased snout-vent length (SVL) of the caller Rana rugosa has an advertisement call tilth a particularly high frequency modulation. We conducted a playback experiment to verify the function of frequency modulation, and investigated the territorial behavior of the frog. The frog has five types of territory defense strategy. Strategy choice depended on the caller's SVL. Small males became satellites or lowered the dominant frequency of their advertisement call, whereas large males actively defended their territory with encounter calls. In response to high frequency (1107 Hz) playback, the frogs lowered their advertisement call frequency, and towered them further in response to the low frequency (1028 Hz) playback. In addition, the number of pulses in a call was increased in response to the playback. These results indicate that the frog avoids physical conflict with competitors by selecting a territory defense strategy suitable for the caller's size, and by lowering its call frequency to disguise its SVL.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.7 no.9
• /
• pp.2268-2283
• /
• 2013

Scalable video coding can handle peer heterogeneity of P2P streaming applications, but there is still a lack of comprehensive studies on how to use it to improve video playback quality. In this paper we propose a capacity aware scalable video coding mechanism for P2P on demand streaming system. The proposed mechanism includes capacity based neighbor selection, adaptive data scheduling and streaming layer adjustment, and can enable each peer to select appropriate streaming layers and acquire streaming chunks with proper sequence, along with choosing specific peers to provide them. Simulation results show that the presented mechanism can decrease the system's startup and playback delay, and increase the video playback quality as well as playback continuity, and thus it provides a better quality of experience for users.