• Title/Summary/Keyword: difference scheme

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A Study on Changes in Indoor Air Pollution by Educational Activities -Centering on Newly-Established Elementary Schools- (교육활동에 따른 실내오염도 변화에 관한 연구 -신설 초등학교를 중심으로-)

  • Jeon, Seok-Jin
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.6 no.2
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    • pp.66-90
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    • 2007
  • The purpose of this study is to measure and analyze primary causes of indoor air pollution, including carbon dioxide, minute dust, and total volatile organic compounds, for each room before the beginning of a class through the time of discharge after the end of the class in general classrooms, computer rooms, and science rooms of three newly-established schools that opened in 2006, examine properties of indoor air environment in each room by educational activities at school, and determine effective management schemes; the results of this study can be summarized as follows: 1) As for implications for each item found in the mean for each place, since minute dust (PM10) was more likely to occur in time slots full of students' activities, such as a traveling class and a recess, than in the middle of a class and could be expected fully, it is necessary to make a scheme for cleaning in order to reduce minute dust within a room, for example, by usually using a vacuum cleaner indoors. 2) While carbon dioxide was expected to vary with the differences in the amount of breath between higher-graders and lower-graders in a general classroom but showed insignificant difference by grades, showing differences in pollution by four times at a maximum according to the opening of a window as expected, it is necessary to implement artificial or natural ventilation and take a positive measure, for example, by presenting a concrete ventilation scheme, in order to improve indoor air pollution at a room practice. 3) Total volatile organic compounds were found to exceed the standard by more than twice in general classrooms, science rooms, and computer rooms of the schools because of building materials, furnitures including desks and chairs, panels and boards for environment beautification, and items which could be detected even from students' clothes; while a field directly-reading tool was used, obtaining high reliability for the results, it is necessary to apply an analytical method based on process test separately for actual correct measurement if a significantly great amount of total volatile organic compounds appear as compared with other schools due to measuring expenses and consecutive measurements. 4) Since formaldehyde (HCHO) was generally found to exceed the standard in general classrooms, science rooms, and computer rooms, it is necessary to establish and operate a ventilator during a class in a computer room which requires airtightness and a science room in which an organic compound should be used for a class.

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Tidal Current and Suspended Sediment Transport in the Keum Estuary,West Coast of Korea (錦江 鹽河口에서의 潮流와 浮游堆積物 이동)

  • 오임상;나태경
    • 한국해양학회지
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    • v.30 no.3
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    • pp.147-162
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    • 1995
  • The circulation due to tidal current and river discharge, and the associated suspended suspended sediment transport in macrotidal Keum Estuary, were studied through a series of field measurements of tidal currents and suspended sediment concentration at three anchored stations from 1990 through 1992. From the measurements, the following results were obtained. At the seaward entrance of the estuary, the veritical profiles of the ebb and flood currents were almost symmetric. At the southern channel the flood current was dominant in the whole water column, but in the northern channel the ebb current was dominant in the surface and bottom layers and the flood current was dominant in the intermediate layer. The maximum velocity of the tidal current in the southern channel was 174 cm/s during flood tide in the intermediate layer. The maximum velocity, 148 cm/s in the northern channel also appeared during flood tide in the intermediate layer. However, in the surface and bottom layers, the maximum velocities were 110.6 cm/s during ebb tide and 92.1 cm/s during flood tide, respectively. The type of the Keum Estuary can be categorized to 'Type 3' of Hansen and Rattray's scheme. The water column of the estuary during the flood tide becomes stratified, and after high water the ebb current reduces the density difference and the water column becomes turbulent. The lower layer of the water column is generally turbulent. The largest sediment flux 20.61 ton/s was found in the southern channel during flood current in the lowest river discharge (May, 1991), while the smallest flux, 0.65 ton/s in the northern channel in the lowest tidal range (July, 1992). The stronger bottom shear velocity for the present study area seems to erode the bottom sediments during the flood tide, and the relatively long duration of the ebb tide to transport the suspended sediments. Under normal river discharge conditions, the suspended sediments are transported mainly through the southern channel. However, under high river discharge condition the suspended sediment transport is dominant through the northern channel.

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Adaptation Techniques of an Object-based MPEG-4 Player to PDA (객체 기반 MPEG-4 재생 기술의 PDA 적응 기법)

  • Kim, Nam-Young;Kim, Sang-Wook
    • Journal of KIISE:Software and Applications
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    • v.33 no.2
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    • pp.220-230
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    • 2006
  • As the computing technique and mobile devices get developed, the demand of multimedia contents for mobile environment has been increased. The multimedia contents provided on PDA has so far been limited to the materials such as video and audio. MPEG-4 is the international standard used for supporting to properly save, communicate multimedia in formation such as video, audio, image, text and two-dimensional object, which can present various, multimedia contents by using adaptation techniques. However, since most MPEG-4 contents are not used for PDA but desktop, it seems not to be played on PDA where needs low power consumption, limited memory capability and GUI, and so on. In this paper, we propose the adaptation techniques, which can present the MPEG-4 contents on PDA, using scene composition with MPEG-4. The proposed scheme consists of three subparts: physical adaptation, variation adaptation and resource adaptation. Physical adaptation adjusts the physical difference of between the authoring environment and playback environment. Event adaptation part transforms events used for desktop to the events used for playback on PDA. The resource adaptation enables efficiency of playback to promote by using the essential information table on BIFS parser. As the proposed scheme is applied to MPEG-4 player, we see that the MPEG-4 contents are efficiently played on PDA.

Encryption Scheme for MPEG-4 Media Transmission Exploiting Frame Dropping (대역폭 감소를 적용한 MPEG-4 미디어 전송시의 암호화 기법 연구)

  • Shin, Dong-Kyoo;Shin, Dong-Il;Park, Se-Young
    • The KIPS Transactions:PartB
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    • v.15B no.6
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    • pp.575-584
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    • 2008
  • According to the network condition, the communication network overload could be occurred when media transmitting. Many researches are being carried out to lessen the network overload, such as the filtering, load distributing, frame dropping and many other methods. Among these methods, one of effective method is frame dropping that reduces specified video frames for bandwidth diminution. B frames are dropped and then I, P frames are dropped according to dependency among the frames in frame dropping. This paper proposes a scheme for protecting copyrights by encryption, when we apply frame dropping to reduce bandwidth of media following MPEG-4 file format. We designed two kinds of frame dropping: first one stores and then sends the dropped files and the other drops frames in real-time when transmitting. We designed three kinds of encryption methods in which DES algorithm is used to encrypt MPEG-4 data: macro block encryption in I-VOP, macro block and motion vector encryption in P-VOP, and macro block and motion vector encryption in I, P-VOP. Based on these three methods, we implemented a digital right management solution for MPEG-4 data streaming. We compared the results of dropping, encryption, decryption and quality of video sequences to select an optimal method, and there is no noticeable difference between the video sequences recovered after frame dropping and the ones recovered without frame dropping. The best performance in encryption and decryption of frames was obtained when we apply the macro block and motion vector encryption in I, P-VOP.

A Preliminary Study on the Establishment of Long-Life Housing Infill Information System (장수명주택 인필 정보시스템 구축에 관한 기초 연구)

  • Jung, Yoon-Hye;Hwang, EunKyoung;Kim, Eun-Young
    • KIEAE Journal
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    • v.17 no.5
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    • pp.51-59
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    • 2017
  • Purpose: This study aims to set up the classification system for providing infill information and draw detailed infill information required by suppliers, thereby promoting the revitalization of long-life housing and utilizing such information as preliminary data for establishing web system, on which infill information required by users in the long-life housing design process are available. Method: For the method of study, the infill information classification system and detailed information were drawn through the analysis of existing building material information systems; and the survey targeting working-level personnel was carried out in order to verify the drawn information system. The results of this study can be summarized as follows. First, the hierarchical classification system (scheme) was selected by quoting the classification system by material type as infill type, after analyzing existing DB information systems and drawing the hierarchical classification system for infill. Second, the comparative analysis between infill was available to users for the detailed infill information of long-life housing, and the essential information and general information were selected for differentiating information. Results: First, the hierarchical classification system (scheme) was selected by quoting the classification system by material type as infill type, after analyzing existing DB information systems and drawing the hierarchical classification system for infill. Second, the comparative analysis between infill was available to users for the detailed infill information of long-life housing, and the essential information and general information were selected for differentiating information. Third, only approximately 30% of the survey respondents recognized the infill of long-life housing, but they did not recognize its difference from existing building materials. Fourth, through the analysis of paths to obtain infill information of long-life housing, it was confirmed that infill information was obtained mostly through books and research papers regarding long-life housing, followed by the existing information systems. The significance of the study lies in that it is differentiated from the previous information system as the information system specialized in the infill of long-life housing was established, and can be used as a measure to revitalize long-life housing market.

Volumetrical changes of liver associated with breathing and its impact to normal tissue complication probability (호흡에 따른 간장용적의 변화와 정상조직손상확율에 미치는 영향에 관한 연구)

  • Cho Jung Hee;Kim Joo Ho;Lee Suk;Park Je Il
    • The Journal of Korean Society for Radiation Therapy
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    • v.13 no.1
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    • pp.14-22
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    • 2001
  • Purpose: The aim of this study is to investigate geometrical and volumetrical changes of liver due to breathing and its impact to NTCP. In order to attain better treatment results it should be considered deliberately during planning session. Mehtods and Materials : Seven patients were examined in this study who have done TACE for accurate tumor margin drawing. After contrast media injection, C-T scan data were obtained in supine position during breathing free, inhalation and exhalation, respectively. For all patients C-T scan were done with same scanning parameters- 5 mm index, 5 mm thickness and pitch 1. Based on C-T data we have measured differences of each variables between breathing status such as changes of total and remained liver volumes, GTV, beam path length and superior to inferior shift. NTCP were calculated using Lyman's effective volume DVH reduction scheme and for this NTCP calculation, the V50 was computed from DVH and each m, n value were referred from Burmans data. Results : The measured total tilter volume and the remained liver volume changed between inspiration and expiration about $1.2-7.7\%(mean+2.7\%)$ and $2.5-13.23\%(mean=5.8\%)$ respectively, and these results were statistically significant(p>0.1). The GTV difference in each patient varied widely from $1.17\%\;to\;30.69\%$, but this result was not statistically significant. Depending on the breathing status, the beam path length was changed from 0.5 cm to 1.1 cm with the average of 0.7 cm, and it was statistically significant(p=0.006). The measured superior to inferior shifts were ranged from 0.5 cm to 3.74 cm. The NTCPs were changed relatively small in each patient, but the variation was large between the patients. The mean NTCP difference was $10.5\%$, with the variation ranged from $7\%\;to\;23.5\%$. Conclusion : Variations of liver volume and of beam path length were changed significantly depending on the breathing statues and the range of variation itself was very different between the patients. Since this variance could seriously affect the clinical outcomes of radiation treatments, the breathing of patients need to be accounted when a final treatment planning is derided.

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The Study of motives to select and revitalise a franchise by comparing management practices of nail shops (네일샵의 경영형태 비교를 통한 프랜차이즈 선택동기와 경영성과 분석에 대한 연구)

  • Lee, Mi-Sun;An, Jong-Sook
    • Journal of Digital Convergence
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    • v.12 no.4
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    • pp.201-211
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    • 2014
  • This study is to identify whether a difference exists between factors that influence the time when independently owned nail shops and franchises commence business. Futhermore, we set out to investigate the criteria for nail shop owners use when selecting franchise nail shops with a relatively high level of customer satisfaction and performance, to discuss the necessity of a franchise agreement. An actual analysis has revealed that there is a difference in factors that influence management at the time of and after the inception of independently owned shops and franchise nail shops. Business performance of franchise shops, as a result of evaluating customer satisfaction or monthly sales, turns out to be higher than independently owned shops. The criteria for selecting franchise stores includes intensity of competitiveness in the same business district, accessibility, ability to keep up with current trends, directors' skills, color scheme, excellence of company logo, interesting interior, reasonable prices compared to the level of cosmetic procedure and efforts to motivate employees. Overall, the deciding factor enabling shops to operate continuously is constant supervision from the headquarters of the franchise company.

Modeling of Earthquake Ground Motion in a Small-Scale Basin (소규모 분지에서의 지진 지반운동 모델링)

  • Kang, Tae-Seob
    • Geophysics and Geophysical Exploration
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    • v.15 no.2
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    • pp.92-101
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    • 2012
  • Three-dimensional finite-difference simulation in a small-scale half-sphere basin with planar free-surface is performed for an arbitrary shear-dislocation point source. A new scheme to deal with free-surface boundary condition is presented. Then basin parameters are examined to understand main characteristics on ground-motion response in the basin. To analyze the frequency content of ground motion in the basin, spectral amplitudes are compared with each other for four sites inside and outside the basin. Also particle motions for those sites are examined to find which kind of wave plays a dominant role in ground-motion response. The results show that seismic energy is concentrated on a marginal area of the basin far from the source. This focusing effect is mainly due to constructive interference of the direct Swave with basin-edge induced surface waves. Also, ground-motion amplification over the deepest part of the basin is relatively lower than that above shallow basin edge. In the small-scale basin with relatively simple bedrock interface, therefore, the ground-motion amplification may be more related to the source azimuth or direction of the incident waves into the basin rather than depth of it.

Spatiotemporal Removal of Text in Image Sequences (비디오 영상에서 시공간적 문자영역 제거방법)

  • Lee, Chang-Woo;Kang, Hyun;Jung, Kee-Chul;Kim, Hang-Joon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.41 no.2
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    • pp.113-130
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    • 2004
  • Most multimedia data contain text to emphasize the meaning of the data, to present additional explanations about the situation, or to translate different languages. But, the left makes it difficult to reuse the images, and distorts not only the original images but also their meanings. Accordingly, this paper proposes a support vector machines (SVMs) and spatiotemporal restoration-based approach for automatic text detection and removal in video sequences. Given two consecutive frames, first, text regions in the current frame are detected by an SVM-based texture classifier Second, two stages are performed for the restoration of the regions occluded by the detected text regions: temporal restoration in consecutive frames and spatial restoration in the current frame. Utilizing text motion and background difference, an input video sequence is classified and a different temporal restoration scheme is applied to the sequence. Such a combination of temporal restoration and spatial restoration shows great potential for automatic detection and removal of objects of interest in various kinds of video sequences, and is applicable to many applications such as translation of captions and replacement of indirect advertisements in videos.

Study on a Suppressor System for Segregation-Distorter Action in Natural Populations of Drosophila melanogaster in Korea (한국산 초파리의 자연집단에 있어서의 SD 요소에 대한 억제요인에 대하여)

  • Chung, Yong-Jai;Kang, Soon-Ja
    • The Korean Journal of Zoology
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    • v.12 no.1
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    • pp.22-28
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    • 1969
  • In order to see if any suppressor system for the SD action was involved in natural populations of D. melanogaster samples from the populations of nine localities in Korea, Choonchun, Yusoo, Namhai, Shinchon(Seoul), Kwangjoo(Kyunggi), Koonsan, Kwangjoo(Chunnam), Jejoo and Pusan were analyzed by using the mating scheme for locating the suppressor on chromosome pairs. And also two kinds of recombinant SD lines R-1, the American line and $R(SD^NH -1)-1$, the Japanese one were used in order to see any difference of the response of the suppressor for differently originated SD. The results of the experiment are given below. (1) The suppressor system was involved in all lines of natural populations from nine localities of Korea. (2) Most of the suppressors were found to be located on the X chromosome and only a few lines from three populations showed to carry the suppressors on the second chromosome and on the third or fourth chromosoem. (3) The response of the suppressor for differently originated SD lines showed no significant difference.

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