• Title/Summary/Keyword: 재귀적

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Combined Image Retrieval System using Clustering and Condensation Method (클러스터링과 차원축약 기법을 통합한 영상 검색 시스템)

  • Lee Se-Han;Cho Jungwon;Choi Byung-Uk
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.1 s.307
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    • pp.53-66
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    • 2006
  • This paper proposes the combined image retrieval system that gives the same relevance as exhaustive search method while its performance can be considerably improved. This system is combined with two different retrieval methods and each gives the same results that full exhaustive search method does. Both of them are two-stage method. One uses condensation of feature vectors, and the other uses binary-tree clustering. These two methods extract the candidate images that always include correct answers at the first stage, and then filter out the incorrect images at the second stage. Inasmuch as these methods use equal algorithm, they can get the same result as full exhaustive search. The first method condenses the dimension of feature vectors, and it uses these condensed feature vectors to compute similarity of query and images in database. It can be found that there is an optimal condensation ratio which minimizes the overall retrieval time. The optimal ratio is applied to first stage of this method. Binary-tree clustering method, searching with recursive 2-means clustering, classifies each cluster dynamically with the same radius. For preserving relevance, its range of query has to be compensated at first stage. After candidate clusters were selected, final results are retrieved by computing similarities again at second stage. The proposed method is combined with above two methods. Because they are not dependent on each other, combined retrieval system can make a remarkable progress in performance.

Study of Parallelization Methods for Software based Real-time HEVC Encoder Implementation (소프트웨어 기반 실시간 HEVC 인코더 구현을 위한 병렬화 기법에 관한 연구)

  • Ahn, Yong-Jo;Hwang, Tae-Jin;Lee, Dongkyu;Kim, Sangmin;Oh, Seoung-Jun;Sim, Dong-Gyu
    • Journal of Broadcast Engineering
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    • v.18 no.6
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    • pp.835-849
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    • 2013
  • Joint Collaborative Team on Video Coding (JCT-VC), which have founded ISO/IEC MPEG and ITU-T VCEG, has standardized High Efficiency Video Coding (HEVC). Standardization of HEVC has started with purpose of twice or more coding performance compared to H.264/AVC. However, flexible and hierarchical coding block and recursive coding structure are problems to overcome of HEVC standard. Many fast encoding algorithms for reducing computational complexity of HEVC encoder have been proposed. However, it is hard to implement a real-time HEVC encoder only with those fast encoding algorithms. In this paper, for implementation of software-based real-time HEVC encoder, data-level parallelism using SIMD instructions and CPU/GPU multi-threading methods are proposed. And we also proposed appropriate operations and functional modules to apply the proposed methods on HM 10.0 software. Evaluation of the proposed methods implemented on HM 10.0 software showed 20-30fps for $832{\times}480$ sequences and 5-10fps for $1920{\times}1080$ sequences, respectively.

3D Building Modeling Using Aerial LiDAR Data (항공 LiDAR 데이터를 이용한 3차원 건물모델링)

  • Cho, Hong-Beom;Cho, Woo-Sug;Park, Jun-Ku;Song, Nak-Hyun
    • Korean Journal of Remote Sensing
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    • v.24 no.2
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    • pp.141-152
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    • 2008
  • The 3D building modeling is one of crucial components in constructing 3D geospatial information. The existing methods for 3D building modeling depend mainly on manual photogrammetric processes, which indeed take great amount of time and efforts. In recent years, many researches on 3D building modeling using aerial LiDAR data have been actively performed to aim at overcoming the limitations of existing 3D building modeling methods. Either techniques with interpolated grid data or data fusion with digital map and images have been investigated in most of existing researches on 3D building modeling with aerial LiDAR data. The paper proposed a method of 3D building modeling with LiDAR data only. Firstly, octree-based segmentation is applied recursively to LiDAR data classified as buildings in 3D space until there are no more LiDAR points to be segmented. Once octree-based segmentation is completed, each segmented patch is thereafter merged together based on its geometric spatial characteristics. Secondly, building model components are created with merged patches. Finally, a 3D building model is generated and composed with building model components. The experimental results with real LiDAR data showed that the proposed method was capable of modeling various types of 3D buildings.

Development of the Protocol of the High-Visibility Smart Safety Vest Applying Optical Fiber and Energy Harvesting (광섬유와 압전 에너지 하베스팅을 적용한 고시인성 스마트 안전조끼의 개발)

  • Park, Soon-Ja;Jung, Jun-Young;Moon, Min-Jung
    • Science of Emotion and Sensibility
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    • v.24 no.2
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    • pp.25-38
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    • 2021
  • The aim of this study is to protect workers and pedestrians from accidents at night or bad weather by attaching optical fiber to existing safety clothing that is made only with fluorescent fabrics and retroreflective materials. A safety vest was designed and manufactured by applying optical fiber, and energy-harvesting technology was developed. The safety vest was designed to emit light using the automatic flashing of optical fibers attached to the film, and an energy harvester was manufactured and attached to drive the light emission of the optical fiber more continuously. As a result, first, the vest wearer' body was recognized from a distance through the optical fiber and retroreflection, which helped prevent accidents. Thus, this concept helps in saving lives by preventing accidents during night-time work on the roadside or activities of rescue crew and sports activities, or by quickly finding the point of an accident with a signal that changes the optical fiber light emission. Second, to use the wasted energy, a piezoelectric-element power generation system was developed and the piezoelectric-harvesting device was mounted. Potentially, energy was efficiently produced by activating the effective charging amount of the battery part and charging it auxiliary. In the existing safety vest, detecting the person wearing the vest is almost impossible in the absence of ambient light. However, in this study, the wearer could be found within 100 m by the light emission from the safety vest even with no ambient light. Therefore, in this study, we will help in preventing and reducing accidents by developing smart safety clothing using optical fiber and energy harvester attached to save lives.

Unforgeable RFID Tag Variable ID Scheme with Efficient Identification (효율적인 식별 기능을 가진 위조 불가 RFID Tag 가변 ID 방식)

  • Choi, Jae-Gwi;Park, Ji-Hwan
    • The KIPS Transactions:PartC
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    • v.11C no.4
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    • pp.447-454
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    • 2004
  • This paper proposes unforgeable RFID variable n scheme with efficient identification. The existing schemes on privacy protection are in efficient because a server should execute identification process with all Tag ID's Information in order to identify a certain Tag. Moreover these schemes have the serious problem that an attacker can forge special tags if he can know tag's secret information stored in the server's database. Our scheme Is required only 2 times exponent computation to identify a tag. The proposed scheme is also secure against leakage of tags information stored in a database, because an attacker cannot forge special tag even if he knows secret information of the server(database).

Secure Oblivious Transfer Protocol-based Digital Fingerprinting Against Conspiracy Attack (공모 공격에 안전한 불확정 전송 프로토콜 기반의 디지털 핑거프린팅 기법)

  • 최재귀;박지환;김태석
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.14 no.3
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    • pp.145-153
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    • 2004
  • Digital fingerprinting schemes are cryptographic methods that a seller can identify a traitor who illegally redistributed digital contents by embedding it into buyer's information. Recently, Josep Domingo-Ferrer suggested an anonymous digital fingerprinting scheme based on committed oblivious transfer protocol. It is significant in the sense that it is completely specified from a computation point of view and is thus readily implementable. But this scheme has the serious problem that it cannot provide the security of buyers. In this paper, we first show how to break the existing committed oblivious transfer-based fingerprinting schemes and then suggest secure fingerprinting scheme by introducing oblivious transfer protocol with two-lock cryptosystem based on discrete logarithm. All computations are performed efficiently and the security degree is strengthened in our proposal.

Type Variations of 'Stepmother' and 'Sister' in the Novels of Park Kyong-Ni and Their Meanings -Focused on Jaegwiyeol, Eunha, Kimyakgukeue Ddaldeul, Nabiwa Unggungkwi (박경리 장편소설의 '계모'·'자매' 유형 변화와 그 의미 -『재귀열』, 『은하』, 『김약국의 딸들』, 『나비와 엉겅퀴』를 중심으로)

  • Cho, Yun-A
    • Journal of Popular Narrative
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    • v.26 no.4
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    • pp.145-181
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    • 2020
  • This study analyzes type variations of the 'stepmother' and 'sister' in the full-length novels of Park Kyong-Ni and attempted to point out their meanings. The pattern of "negative stepmother" that appeared in classical and new novels also appeared repeatedly in Park Kyong-Ni's full-length novels and this was because a change took place in later full-length novels. Novels analyzed with focus were Jaegwiyeol(1959), Eunha(1960), Kimyakgukeue Ddaldeul(1962), and Nabiwa Unggungkwi(1969). The stepmother that appears in Eunha is a type that appears often in the classic and new novels of Korea. While the stepmother newly gained the role and status of 'mother', she forms a competitive relationship with the daughter of the former wife while still refusing to be a member of the family and she puts the former wife's daughter in critical situations by committing misdeeds. However, the young stepmother in Nabiwa Unggungkwi actually becomes a victim to the malicious and morbid harassment of the former wife's daughter. This stepmother is a good-natured figure who shows a sense of guilt for failing to fulfill her responsibilities of upbringing and education and she eventually dies as a victim to a bomb during the war, leaving her young biological daughter behind. On one hand, the sisters in Jaegwiyeol and Kimyakgukeue Ddaldeul are not strongly bonded but when one is caught in a crisis, the other one claims to be of help. Unlike this, the sisters in Nabiwa Unggungkwi have a bond that cannot be broken. They are half-sisters that bind each other so severely that they hinder each other's growth and they eventually end up disintegrating. Through such analyses, it is shown that issues of human nature are dealt with more acutely by breaking the 'young stepmother' away from convention by placing her in the position of the victim to amplify the conflicting relationship between sisters, unlike in previous pieces. This study was significant in that it looked into how previously repetitive character type changes appeared in full-length novels in conditions that clearly display the writer's determination to leave behind a masterpiece.

An Efficient Path Expression Join Algorithm Using XML Structure Context (XML 구조 문맥을 사용한 효율적인 경로 표현식 조인 알고리즘)

  • Kim, Hak-Soo;Shin, Young-Jae;Hwang, Jin-Ho;Lee, Seung-Mi;Son, Jin-Hyun
    • The KIPS Transactions:PartD
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    • v.14D no.6
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    • pp.605-614
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    • 2007
  • As a standard query language to search XML data, XQuery and XPath were proposed by W3C. By widely using XQuery and XPath languages, recent researches focus on the development of query processing algorithm and data structure for efficiently processing XML query with the enormous XML database system. Recently, when processing XML path expressions, the concept of the structural join which may determine the structural relationship between XML elements, e.g., ancestor-descendant or parent-child, has been one of the dominant XPath processing mechanisms. However, structural joins which frequently occur in XPath query processing require high cost. In this paper, we propose a new structural join algorithm, called SISJ, based on our structured index, called SI, in order to process XPath queries efficiently. Experimental results show that our algorithm performs marginally better than previous ones. However, in the case of high recursive documents, it performed more than 30% by the pruning feature of the proposed method.

Fast PU Decision Method Using Coding Information of Co-Located Sub-CU in Upper Depth for HEVC (상위깊이의 Sub-CU 부호화 정보를 이용한 HEVC의 고속 PU 결정 기법)

  • Jang, Jae-Kyu;Choi, Ho-Youl;Kim, Jae-Gon
    • Journal of Broadcast Engineering
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    • v.20 no.2
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    • pp.340-347
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    • 2015
  • HEVC (High Efficiency Video Coding) achieves high coding efficiency by employing a quadtree-based coding unit (CU) block partitioning structure and various prediction units (PUs), and the determination of the best CU partition structure and the best PU mode based on rate-distortion (R-D) cost. However, the computation complexity of encoding also dramatically increases. In this paper, to reduce such encoding computational complexity, we propose three fast PU mode decision methods based on encoding information of upper depth as follows. In the first method, the search of PU mode of the current CU is early terminated based on the sub-CBF (Coded Block Flag) of upper depth. In the second method, the search of intra prediction modes of PU in the current CU is skipped based on the sub-Intra R-D cost of upper depth. In the last method, the search of intra prediction modes of PU in the lower depth's CUs is skipped based on the sub-CBF of the current depth's CU. Experimental results show that the three proposed methods reduce the computational complexity of HM 14.0 to 31.4%, 2.5%, and 23.4% with BD-rate increase of 1.2%, 0.11%, and 0.9%, respectively. The three methods can be applied in a combined way to be applied to both of inter prediction and intra prediction, which results in the complexity reduction of 34.2% with 1.9% BD-rate increase.

Survey on the Effect of the Parity on Reproductive Traits of Korean Native Cows (산차가 한우번식에 미치는 영향에 대한 조사 연구)

  • 백광수;고응규;성환후;이명식;류일선;정진관;나승환
    • Korean Journal of Animal Reproduction
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    • v.22 no.4
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    • pp.359-366
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    • 1998
  • A survey was carried out to investigate the effect of the parity on reproductive traits of Hanwoo(Korean native cows). Data on the reproductive traits of 670 Korean native cows were collected from January, 1996 to December, 1997 and analyzed by the parity. The results obtained were summarized as follows; 1. The average ages at first breeding, first conception and first calving were 443.0, 457.0 and 746.6 days, respectively. 2. The average days to first estrus after calving was 70.1 days and it was shortest in the cows with more than 5 parities (60.4 days) and longest in the cows at 4th parity (79.7 days). 3. The average number of services per conception was 1.53 and it was fewer in the cows at 2nd paity (1.43), but more in the cows with more than 5 parities (1.73). 4. The average days to first conception after calving was 91.2 days and there was a trend that it was longer as the parity of cows increased(p>0.05). 5. The average length of calving interval was 375.3 days and it was shortest in the cows at 2nd cows (370.8 days) and longest in the cows at 4th parity (395.2 days).

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