소프트웨어 정의 네트워크 기반 오픈플로우 프로토콜

김응성,김진홍,김정식 한국지식정보기술학회 2022 한국지식정보기술학회 논문지 Vol.17 No.4

Recently, newly software defined network technology method is becoming for the future internet research, which has been proposed to experiment with big data system and hybrid AI system so on. In addition, software defined network technology, which has recently become a major concern among communication-related technologies, can solve the limitations of existing network equipment and provide more diverse experiences to users. Many companies that are far from network equipment such as Facebook and Huawei have developed in concerned with software defined network equipment/services. Such as, it will be a very near future for software defined networks could be define realistic individual security its protocol and also their equipment process are improved. Nevertheless, they have some problem how solve an applicable from software defined network to hardware. First, in a software defined network, there is a problem that must be solved in advance in order to provide a safe network environment to users. Second, it is a matter of securing reliability of network packets transmitted through different network devices. It remains an issues whole environment including standardization, cooperation between various existing network equipment their companies. Accordingly, we propose about software defined network using the OpenFlow in this research. Especially, our research approach method provide confidentiality and integrity security services by adding an authentication process for data transmitted between the OpenFlow switch and the controller.

Research on Intelligent Dynamic Software Architecture Using Style-based Modeling

김응성,김진홍,김정식 한국지식정보기술학회 2021 한국지식정보기술학회 논문지 Vol.16 No.4

A good architectural design allows to capture the overall complexity of large, distributed systems at a higher level of abstraction. This is especially important for reconfigurable systems where the architectural configuration is subject to changes at runtime. When designing such a dynamic architecture, the software architect has to bring the functional business requirements and the available communication and reconfiguration mechanisms of the intended target platform in line. As it is a complex task to incorporate these often diverging requirements into the architectural model, we propose a stepwise approach similar to the MDA initiative. We start with a platform-independent model capturing the business requirements and add platform-specific details in a later step. For each level of platform abstraction and associated platform, we define an architectural style which describes the characteristics of the platform. This way, conformance to the architectural style entails consistency between model and the underlying platform. Besides run-time configurations of components and connections, architectural models also comprise the description of processes that control the communication and reconfiguration behavior. To provide operational semantics, we formalize architectural models as graphs and architectural styles as graph transformation systems. Due to the stepwise procedure, we also have to ensure the mutual consistency between models at different levels of abstraction. For this purpose, we define formal refinement criteria which require that both structural and behavioral properties are preserved at the lower level of abstraction.

웨이브렛 變換을 利用한 3次元 스칼라 영상 데이터 壓縮

김응성,조성환 대한전자공학회 2004 電子工學會論文誌 IE (Industry electronics) Vol.41 No.03

본 논문에서는 웨이브렛 변환을 이용한 3차원 스칼라 데이터 압축 알고리듬을 제안한다. 먼저 3차원 영상을 입력받아 웨이브렛 변환을 적용하는 영역을 한정시킨 후, 웨이브렛 변환 과정을 거친 데이터들에 대해 양자화 적용 범위를 결정짓고 양자화를 수행한다. 각각의 웨이브렛 변환된 영역을 크게 네 부분으로 나누고 그에 대해서 동일한 양자화 계수를 적용시켰다. 분류과정은 각 영역에서의 고주파 특성의 분포의 개수가 동일한 것을 기준으로 하였다. 0이 아닌 중요계수의 크기 정보를 부호화하는데 있어서 대칭적 양방향 트리 구조를 이용하였고, 중요 계수의 위치 정보를 부호화하는 데에는 제로트리 루트의 위치 정보를 줄길이 부호화하였다. 실험 결과로 제안한 알고리듬이 3차원 DCT를 사용한 방법에 비해 더 좋은 화질을 나타내는 것을 알 수 있었다. This paper proposes 3D scalar data compression technique using wavelet transform. At first, after inputting 3D image and restricting range applied wavelet transform, we decided quantization appling field about data accomplished wavelet transform process. And then the quantization is executed. Each wavelet transformed range was divided into four parts and the same quantization coefficients were applied to those parts. The classification process has criterion to check whether distributed number of high frequency specification is equal. When the size information of nonzero coefficients is coded, symmetrically bidirectional tree structure was used and when the position information of coefficients is coded, run length coding about position information of zerotree root was executed. Simulation results show that the proposed algorithm has better quality than the method using 3D DCT.

역전파 알고리듬과 사전을 이용한 필기체 영문자 인식

김응성,조성환,이근영 한국통신학회 1993 韓國通信學會論文誌 Vol.18 No.2

In this paper, it is shown that neural networks trained with back propagation algorithm and dictionary can be applied to recognize handwritten English characters. To eliminate the useless data part and to minimize the variety of characters from the scanned image file, various preprocessings : that is, segmentation, centering, noise filtering, sealing and thinning are performed. After these, characteristic features are derived from thinned character pattern. The neural network is trained by using the extracted features for sample data, and all test data are classified into English alphabets according to their features through the neural network. Finally, the ways of reducing learning time and improving recognition rate, and the relationship between learning time and hidden layer nodes are considered. As a result of this study, after successful training, a high recognition rate has been obtained with this system for the trained patterns and about 93% for test patterns. Using dictionary, the recognition rate was about 97% for test pattern. 본 논문에서는 역전파 알고리듬으로 학습된 신경회로망과 사전을 이용하여 필기체 영문자 인식을 수행하였다. 스캐너를 이용하여 입력된 영상화일로부터 불필요한 데이터 부분을 제거하고 문자의 다양성을 최소화하기 위해서 여러가지 전처리과정, 즉 문자분리, 중심변환, 잡음제거, 배율조정과 세선화과정을 거쳤다. 다음으로 세선화된 문체 패턴으로부터 문자의 특징이 추출되고, 신경회로망에 시험데이터에 대한 특징들을 학습시켰다. 그리고 테스트할 영문자에 대해서도 특징들을 추출하여 이미 학습된 신경회로망에 의해 분류하였다. 마지막으로 학습시간을 줄이고 인식율을 향상시키기 위한 방법과 학습시간과 은닉층의 노드수에 대해 고찰하였다. 실험 결과로서 이와 같은 시스템으로 필기체 영문제에 대하여 학습후에 약 93%의 높은 인식율을 얻을 수 있었을 사전을 이용했을 경우 인식율이 약 97%였다.

윤관선 분류 유한상태 벡터 양자화를 이용한 영상 시퀀스 부호화

김응성,이근영 한국통신학회 1998 韓國通信學會論文誌 Vol.23 No.9

In this paper, we propose a new edge based finite state vector quantization method having better performance than conventional side-match finite state vector quantization. In our proposed scheme, each dCT transformed block is classified to 17 classes according to edge types. Each class has a different codebook based on its characteristis. Encoder classified each block to motion block or stationary block and constructed a merging map by using edge and motion information, and sent to decoder. We controled amoutn of bing bits transmitted with selecting modes accoridng to bandwidth of transmitting channel. Compared with conventional algorithms, H.263 and H.261 at low bit rate, our proposed algorithm shows better picture quality and good performance.

선박의 대기오염방지 규제 강화에 대비한 역량강화

김응성(E-S Kim) 한국마린엔지니어링학회 2008 한국마린엔지니어링학회지 Vol.32 No.5

DCT와 블록 계층 분할 유한상태 벡터 양자화를 이용한 영상 부호화

조성환,김응성,Jo, Seong-Hwan,Kim, Eung-Seong 한국정보처리학회 2000 정보처리논문지 Vol.7 No.3

In this paper, we propose an algorithm which segments hierarchically blocks of image using discrete cosine transform(DCT) and execute finite-state vector quantization (FSVQ) for each block. Using DCT coefficient feature, image is segmented hierarchically to large smooth block and small edge block, then the block hierarchy informations are transmitted. The codebooks are respectively constructed for each hierarchical blocks, the encoder transmits codeword index using FSVQ for reducing encoded bit with hierarchical segmentation. Compared with side match VQ(SMVQ) and hierarchical FSVQ(HFSVQ) algorithm, about Zelda and Boat image, the new algorithm shows better picture quality with 1.97dB and 2.85 dB difference as to SMVQ, 1.78dB and 1.85dB diffences as to HFSVQ respectively.

DCT계수의 재배열을 통한 웨이브렛 변환 형식의 정지 영상 부호화

김정식,김응성,이근영,Kim, Jeong-Sik,Kim, Eung-Seong,Lee, Geun-Yeong 대한전자공학회 2001 電子工學會論文誌-SP (Signal processing) Vol.42 No.3

DCT(Discrete Cosine Transform)는 공간 영역과 주파수 영역을 균등하게 분할함으로써 인간의 시각특성을 제대로 반영하지 못하는 단점이 있다. DCT의 영역 분할에 대한 단점을 극복할 수 있는 알고리듬으로 웨이브렛 변환을 이용하여 영상을 부호화하는 여러 가지 기법들이 있지만, 본 논문에서는 DCT와 웨이브렛 변환의 장점을 결합한 새로운 알고리듬을 제안한다. 제안 방법은 DCT의 DC 계수에 에너지 집중도가 좋은 장점을 효과적으로 이용함과 더불어 이들 계수들을 웨이브렛 변환 형식에 적용한다. 웨이브렛 상의 대역간 상관 관계와 대역내 상관 관계를 동시에 효율적으로 이용하고 각 대역 특성별로 양자화를 수행하며, 부호화 방법에 대해서도 중요 계수 정보·지 양자화 계수들은 대칭적인 분포를 나타내며 절대값이 커질수록 발생확률이 감소하는 특징을 이용하여 알고리듬이 간단하고 복호화 시간이 빠른 장점을 가지는 대칭적 양방향 트리 구조의 새로운 방법을 제시한 전지 영상 압축 부호화 알고리듬을 제안하였다. JPEG 알고리듬과 제안 알고리듬을 비교하였을 때, 동일한 비트율에서 제안 알고리듬이 객관적 화질뿐만 아니라 주관적으로도 높은 화질의 영상을 얻을 수 있었다. Since DCT algorithm divides an image into blocks uniformly in both the spatial domain and the frequency domain, it has a weak point that it can not reflect HVS(Human Visual System) efficiently To avoid this problem, we propose a new algorithm, which combines only the merits of DCT and wavelet transform. The proposed algorithm uses the high compaction efficiency of DCT, and applies wavelet transform mode to DCT coefficients, so that the algorithm can utilize interband and intraband correlations of wavelet simultaneously After that, the proposed algorithm quantizes each coefficient based on the characteristic of each coefficient's band. In terms of coding method, the quantized coefficients of important DCT coefficients have symmetrical distribution, the bigger that value Is, the smaller occurrence probability is. Using the characteristic, we propose a new still image coding algorithm of symmetric and bidirectional tree structure with simple algorithm and fast decoding time. Comparing the proposed method with JPEG, the proposed method yields better image quality both objectively and subjectively at the same bit rate.

영상 부호화를 위한 이산 여현변환 기반의 계층적 유한 상태 벡터 양자화 기법

남일우,김응성,이근영 대한전자공학회 1998 電子工學會論文誌, S Vol.s35 No.1

In this paper, we introduce a new DCT based hierarchical finite state vector quantization. Our proposed scheme uses difference of DCT coefficients to find a representative vector, and classifies image blocks into different hierarchical levels depending on their structural characteristics, and uses different coding rates and different number os state codebooks at each hierarchical levels. As a result, we obtained reconstructed images having satisfiable quality objectively.

움직임 벡터의 공간적 분포에 기반한 움직임 추정 기법 ( A Motion Estimation Algorithm Based on Spatial Distribution of Motion Vector )

남일우,김응성,최중한,이근영 대한전자공학회 1996 대한전자공학회 학술대회 Vol.1996 No.1