• 제목/요약/키워드: Concealment Technique

검색결과 66건 처리시간 0.022초

선택적 방향성 보간을 이용한 효율적인 공간적 에러은닉 기법 (An Efficient Spatial Error Concealment Technique Using Selective Edge-Oriented Interpolation)

  • 박선규;김원기;진순종;정제창
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2006년도 학술대회
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    • pp.77-80
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    • 2006
  • 본 논문에서는 블록 기반의 영상압축에 있어서 선택적 방향성 보간을 이용하는 공간적 에러 은닉 기법을 제안한다. 기존의 공간적 경계 정합 기법은 에지가 단순한 영역에서는 좋은 성능을 보이지만, 손실 블록 내에서 에지의 변화가 큰 영역에서는 좋지 못한 성능을 보인다. 제안된 기법은 이웃한 상하 블록들을 이용하여 에지의 연결성을 추정하고, 이에 따라 공간적 경계정합 기법과 이동 스트라이프 정합 기법을 선택적으로 이용한다. 따라서 에지변화에 적응적으로 대응함으로써 우수한 복원영상을 구할 수 있다. 제안된 기법은 슬라이스 단위의 에러에 대해 적합한 방식으로써, 복잡도가 낮을 뿐만 아니라 객관적 주관적으로 우수한 복원 화질을 얻게 해준다.

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Whitening Transform을 이용한 Multiple Description Coding (Multiple Description Coding using Whitening Transform)

  • 최광표;이근영
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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    • pp.41-44
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    • 2002
  • In the communications systems with diversity, we are commonly faced on needing of new source coding technique, error resilient coding. The error resilient coding addresses the coding algorithm that has the robustness to unreliability of communications channel. In recent years, many error resilient coding techniques were proposed such as data partitioning, resynchronization, error detection, concealment, reference picture selection and multiple description coding (MDC). In this paper, we proposed an MDC using whitening transform. The conventional MDC using correlating transform is need additional information to decode the image. But, if an image is transformed using the whitening transform, the additional information is not necessary to transform because the coefficients of whitening transform have uni-variance statistics.

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스토리텔링구현을 통한 농촌관광마을에서의 장소성확보 -개실마을의 사례를 중심으로- (Securing Placeness at Rural Tourism Village Via Storytelling Implementation -Focusing on Case study of Gaesil Village-)

  • 이병훈
    • 농촌계획
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    • 제18권1호
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    • pp.47-57
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    • 2012
  • The following study has examined possible methodological approach and prospect of implementing storytelling in rural tourism field. It is aimed towards deducing principles of space composition behind securing placeness of rural tourism village through storytelling. The research had been conducted by archival research and case study on field of interest, and its findings are as follows: 1) Storytelling exhibits principles of narrative structure (exposition, complication, climax, and resolution) in various fields, and has shown tendency to structuralize a plot. 2) It can be said that storytelling is deeply related with people's associations of their inner mind. This can be a logical explanation of a certain sight or location, which is a physical environment itself being the actual narrator and distributor in storytelling. 3) In order to convey a story in a more convincing way, storytelling a naming strategy based on a rhetorical technique, which has been shown to positively influence creating unique placeness of a rural village. As indicated in our study, means of storytelling-"Continuity and tourist circulation of space composition with a narrative structure, spatial hierarchical order, concealment and revelation, cast, and naming based on rhetorical technique and facilities positioning"-is a viable solution that can bring recovery of the rural village's unique placeness, as well as spatial development for sustainable rural tourism.

Generalized Self Spread-Spectrum Communications with Turbo Soft Despreading and Decoding

  • Tomasin Stefano;Veronesi Daniele
    • Journal of Communications and Networks
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    • 제8권3호
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    • pp.267-274
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    • 2006
  • Self-spreading (SSP) is a spread spectrum technique where the spreading sequence is generated from data bits. Although SSP allows communications with low probability of interception by unintended receivers, despreading by the intended receiver is prone to error propagation. In this paper, we propose both a new transmitter and a new receiver based on SSP with the aim to a) reduce error propagation and b) increase the concealment of the transmission. We first describe a new technique for the generation of SSP spreading sequence, which generalizes SSPs of existing literature. We include also coding at the transmitter, in order to further reduce the effects of error propagation at the receiver. For the receiver, we propose a turbo architecture based on the exchange of information between a soft despreader and a soft-input soft-output decoder. We design the despreader in order to fully exploit the information provided by the decoder. Lastly, we propose a chip decoder that extracts the information on data bits contained in the spreading sequence from the received signal. The performance of the proposed scheme is evaluated and compared with existing spread-spectrum systems.

A study on Countermeasures by Detecting Trojan-type Downloader/Dropper Malicious Code

  • Kim, Hee Wan
    • International Journal of Advanced Culture Technology
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    • 제9권4호
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    • pp.288-294
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    • 2021
  • There are various ways to be infected with malicious code due to the increase in Internet use, such as the web, affiliate programs, P2P, illegal software, DNS alteration of routers, word processor vulnerabilities, spam mail, and storage media. In addition, malicious codes are produced more easily than before through automatic generation programs due to evasion technology according to the advancement of production technology. In the past, the propagation speed of malicious code was slow, the infection route was limited, and the propagation technology had a simple structure, so there was enough time to study countermeasures. However, current malicious codes have become very intelligent by absorbing technologies such as concealment technology and self-transformation, causing problems such as distributed denial of service attacks (DDoS), spam sending and personal information theft. The existing malware detection technique, which is a signature detection technique, cannot respond when it encounters a malicious code whose attack pattern has been changed or a new type of malicious code. In addition, it is difficult to perform static analysis on malicious code to which code obfuscation, encryption, and packing techniques are applied to make malicious code analysis difficult. Therefore, in this paper, a method to detect malicious code through dynamic analysis and static analysis using Trojan-type Downloader/Dropper malicious code was showed, and suggested to malicious code detection and countermeasures.

Axillary Reconstruction for Hidradenitis Suppurativa with an Inner-Arm Transposition Flap Creating a Brachioplasty Effect

  • Ching, Daniel L.;Mughal, Maleeha;Papas, Athanasios;Soldin, Mark
    • Archives of Plastic Surgery
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    • 제44권3호
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    • pp.228-233
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    • 2017
  • Background Hidradenitis suppurativa (HS) is a chronic skin condition that can affect any area with apocrine sweat glands and has the potential to involve multiple sites concurrently. Commonly affected sites include the axilla, groin, perineum and perianal areas. In this study we performed a literature review on the surgical methods for HS and describe an innovative technique for reconstructing axilla HS using an inner-arm transposition flap. Methods We reviewed all cases (5 cases from 4 patients) of transposition flap reconstruction performed by the senior author at a single London tertiary hospital from 2008-2013. Patient related outcome measures were collected using the Derriford appearance scale (DAS 24) and a study specific questionnaire. Results All patients were satisfied with their final result. One out of five cases had a complication but did not result in flap failure. There is no disease recurrence to date. DAS 24 scores collected demonstrated acceptable postoperative distress that did not deviate far from the norm tables while study specific questionnaire reveal desirable outcomes. Conclusions We have managed to achieve our aim through the use of the innovative inner-arm transposition flap. Our study hopes to provide an additional technique for axillary reconstruction. This technique offers the effective concealment of scars with the benefit of tightening of the arm tissue producing 'brachioplasty like' effects. All things considered it would be reasonable to conclude the innovative flap technique is a reliable, effective, and simple method that results in multiple benefits.

인터넷 기반의 MPEG-4 스트리밍 서비스를 위한 적응적 QoS 관리 (Adaptive QoS Management for MPEG-4 Streaming Service over Internet)

  • 최지훈;이상조;서덕영;김현철;이명호
    • 방송공학회논문지
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    • 제5권2호
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    • pp.227-238
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    • 2000
  • 본 논문에서 여러 가지 실험을 통한 결과를 분석한 결과. 인터넷망의 QoS는 어느 정도 일정한 패턴을 가지고 있다는 것을 파악하였다. 첫째 이러한 패턴을 분석함으로써 손실률과 손실 패턴에 따라 재전송 및 FEC(Forward Error Correction)의 정도를 달리하고 시간적 계층부호화(temporal scalability)를 이용하여 비트율을 변경시키는 보다 효율적이고 적응적 QoS 관리 방법을 제시한다. 둘째, MPEG-4의 오류 강인성을 이용한 비디오 패킷 단위의 전송으로 인해 오류 전파를 막고, Network상의 패킷 손실을 디코더에서 오류 은닉을 할 수 있도록 한다. 셋째, 네트워크상의 패킷 손실을 최소화할 수 있는 방법으로 GOP(Group Of Picture) 단위의 전송으로 인한 인터리빙(interleaving) 효과와 FEC를 이용하여 수신측에서 패킷 손실을 정정하고 다소 지연이 발생하지만 손실률을 줄이기 위해 재전송(retransmission) 등을 이용하였다. 마지막으로, 제안된 알고리듬들을 적용한 MPEG-4 스트리밍 서비스를 위한 VOD 시스템을 구현하였다.

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복식에 표현된 노출 (Exposure Expressed in Dress)

  • 정연자
    • 한국의상디자인학회지
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    • 제1권1호
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    • pp.91-107
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    • 1999
  • The primary purpose of this study is to inquire into the characteristic of exposure presented in fashion, identify the correct concept of exposure from an aesthetic perspective, and grasp the contemporary meaning of exposure presented in fashion. As a result of study, the following findings were obtained: First, the surrealist style of fashion exhibited representations such as the relocation of the partial details, the harmonization of the natural and the artificial, the emphasis or expansion of each part of the body, and the like. It used highlighted the genital region with ornamentations or used the technique of paradoxically exposing the part of the body always covered. And it exbibited the paradoxical relationship of exposure and concealment by exposing the concealed part of the human body. Second, the post-modern style showed the complicated phenomenon that the values of several meanings such as the historic, the folk, and the like appeared in its fashion. It shares in spatiotemporal eclecticism, pluralistic characteristics and the like found in the post-modern culture. Third, the deconstructive style gets rid of the distinction between the external space and the private space by translating underwears into outer garments. It destroys clothing by tearing or perforating clothing whereby it represents the poor image. Coupled with women‘s psychology of exposure and the new generation’s way of thinking indifferent to others‘ eyes, this fashion of deconstruction occupies the great current of fashion. Deconstructive fashion gets away with the rule of ‘having to wear clothing to suit TPO(Time, Place and Occasion), the traditional norm of wearing clothing.

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Multiple Description Coding using Whitening Ttansform

  • Park, Kwang-Pyo;Lee, Keun-Young
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.1003-1006
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    • 2002
  • In the communications systems with diversity, we are commonly faced on needing of new source coding technique, error resilient coding. The error resilient coding addresses the coding algorithm that has the robustness to unreliability of communications channel. In recent years, many error resilient coding techniques were proposed such as data partitioning, resynchronization, error detection, concealment, reference picture selection and multiple description coding (MDC). Especially, the MDC using correlating transform explicitly adds correlation between two descriptions to enable the estimation of one set from the other. However, in the conventional correlating transform method, there is a critical problem that decoder must know statistics of original image. In this paper, we propose an enhanced method, the MDC using whitening transform that is not necessary additional statistical information to decode image because the DCT coefficients to apply whitening transform to an image have uni-variance statistics. Our experimental results show that the proposed method achieves a good trade-off between the coding efficiency and the reconstruction quality. In the proposed method, the PSNR of images reconstructed from two descriptions is about 0.7dB higher than conventional method at the 1.0 BPP and from only one description is about 1,8dB higher at the same rate.

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A New Technique for Conchal Cartilage Harvest

  • Kim, Joon Young;Yang, Ho Jik;Jeong, Ji Won
    • Archives of Plastic Surgery
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    • 제44권2호
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    • pp.166-169
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    • 2017
  • The goal of auricular cartilage harvest is to obtain a sufficient amount for reconstruction and to minimize the change in ear shape. The cartilage can be harvested by a posterior or anterior approach, and each method has advantages and disadvantages. The posterior approach presents the advantage of scar concealment, but there are limits to the amount of cymba cartilage that may be harvested. In contrast, the anterior approach may cause a noticeable scar. However, as cartilage is collected, the anterior approach provides a view that facilitates the preservation ear structure. In addition, it is possible to obtain a greater amount of cartilage. From January 2014 to December 2015, we harvested auricular cartilage graft material in 17 patients. To prevent the development of trapdoor scars or linear scar contracture, short incisions were made on the superior border of the cymba and cavum. Two small and narrow incisions were made, resulting in suboptimal exposure of the surgical site, which heightens the potential for damaging the cartilage when using existing tools. To minimize this, the authors used a newly invented ball-type elevator. All patients recovered without complications after surgery and reported satisfaction with the shape of the ear.