• 한국차세대컴퓨팅학회논문지
• /
• 제13권2호
• /
• pp.18-25
• /
• 2017

인코딩(encoding)은 컴퓨터에서 사용되는 음성, 영상 및 텍스트 문자를 부호화하는 방법을 가리킨다. 그러므로 특정 데이터를 열람하기 위해서는 해당 인코딩 정보를 알아야하며, 데이터마다 인코딩을 판별해주는 알고리즘들이 존재한다. 하지만 실제 음원이나 문서를 송수신하는 과정에서 패킷 손실이 발생할 수 있으며, 특히 무선 통신망에서 패킷 스니핑으로 정보를 가로챌 경우 손실률은 더욱 증가되어 인코딩 기법 판별에 어려움이 발생한다. 본 논문에서는 이러한 오류가 발생한 데이터의 인코딩 기법 판별율을 향상시키기 위해 기존의 문자 인코딩 기법 판별 프로그램인 'uchardet'에 Bit-shift 알고리즘을 적용하여 성능 향상을 이루었다. 알고리즘의 성능 평가를 위해 임의의 한글 및 일본어 텍스트 파일에 손실률(loss rate)을 적용하여 부분적으로 데이터가 소실된 인코딩 파일을 생성하여 결과를 비교하였다. 그 결과, 패킷이 손실된 데이터에서 Bit-shift 알고리즘을 적용한 'uchardet-bitshift' 경우 기존의 알고리즘보다 더 나은 성능을 보였다. 한국어 인코딩의 경우 기존의 uchardet는 0.005% 손실률까지 100%의 정확도를 보이고 1%보다 높은 손실률에서는 인코딩을 전혀 판별해 내지 못한데 비해, Bit-shift 알고리즘을 적용할 경우 0.05%의 손실률에도 100%의 정확도를 보였으며 그보다 큰 손실률에서도 해당 인코딩을 판별해냈다. 또한 한자어를 많이 포함하는 일본어의 경우 손실률이 높아질수록 중국어 인코딩으로 잘못 판별하는 경향을 보였다. 시뮬레이션 분석 결과, Bit shift 알고리즘을 추가하여 기존 인코딩 기법 판별 알고리즘의 개선이 가능하였다.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
• /
• pp.663-666
• /
• 2005

The Geography Markup Language (GML) is an XML encoding for the transport and storage of geographic information, including both the geometry and properties of geographic features. This paper uses the GML to provide extendibility and interoperability of spatial data in moving objects management system. Since the purpose of the system is to provide locations of the moving objects in the web and mobile environments, we used the GML both for presenting map data and trajectories of the moving objects. The proposed system is composed of Location Data Interface, Moving Objects Engine, and Web/Mobile Presentation Interface. We utilized the concept of Web Map Server, that is web mapping technology of OGC (Open Geospatial Consortium), to integrate map data and the location information of the moving objects. In the process of the integration, we used the standard data model and interfaces while defining new application schema. Since our suggested system uses open spatial data encoding and interfaces, both extendibility and interoperability are guaranteed.

• 대한임베디드공학회논문지
• /
• 제18권1호
• /
• pp.1-7
• /
• 2023

In this paper, we implement a lossless compression technique for time-series data generated by IoT (Internet of Things) devices to reduce the disk spaces. The proposed compression technique reduces the size of the encoded data by selectively applying CNN (Convolutional Neural Networks) or Delta encoding depending on the situation in the Forecasting algorithm that performs prediction on time series data. In addition, the proposed technique sequentially performs zigzag encoding, splitting, and bit packing to increase the compression ratio. We showed that the proposed compression method has a compression ratio of up to 1.60 for the original data.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2000년도 가을 학술발표논문집 Vol.27 No.2 (2)
• /
• pp.529-531
• /
• 2000

본 논문은 Geometry Compression 분야에서 다뤄지는 압축기법 중 delta encoding 과정을 보완하여 좀 더 높은 압축률을 얻고자 하는 vertex position prediction 과정에 대한 내용으로 구성되어 있다. 이것은 triangle strip 형태의 입력을 받아서 그 vertex data 중 position 정보들간의 delta encoding 과정을 예측 기법을 이용한 encoding 과정으로 대체하여 Huffman encoding 과정에서의 symbol 개수를 줄여 압축률을 향상시키자는 개념에서 출발한다. triangle strip 생성 기법 중 greedy algorithm을 적용한 후, 기존의 parallelogram 방식과 이 논문에서 새로이 제안하는 방식을 비교하여 보다 나은 압축 방식을 제시하는 것이 이 논문의 목적이다. 이 논문에서 제시하는 방식을 실험한 결과, 기존의 예측 기법에 비해 2.4% 정도의 향상을 보여주고 있다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권8호
• /
• pp.2849-2864
• /
• 2021

The emerging of cloud data sharing can create great values, especially in multi-cloud environments. However, "data island" between different cloud service providers (CSPs) has drawn trust problem in data sharing, causing contradictions with the increasing sharing need of cloud data users. And how to ensure the data value for both data owner and data user before sharing, is another challenge limiting massive data sharing in the multi-cloud environments. To solve the problems above, we propose a Uniform Encoding and Parsing Framework (UEPF) with blockchain to support trustworthy and valuable data sharing. We design namespace-based unique identifier pair to support data description corresponding with data in multi-cloud, and build a blockchain-based data encoding protocol to manage the metadata with identifier pair in the blockchain ledger. To share data in multi-cloud, we build a data parsing protocol with smart contract to query and get the sharing cloud data efficiently. We also build identifier updating protocol to satisfy the dynamicity of data, and data check protocol to ensure the validity of data. Theoretical analysis and experiment results show that UEPF is pretty efficient.

• Journal of the Optical Society of Korea
• /
• 제18권2호
• /
• pp.129-133
• /
• 2014

In this paper, we propose a simple Double random phase encryption (DRPE)-based orthogonal encoding technique for color image encryption. In the proposed orthogonal encoding technique, a color image is decomposed into red, green, and blue components before encryption, and the three components are independently encrypted with DRPE using the same key in order to decrease the complexity of encryption and decryption. Then, the encrypted data are encoded with a Hadamard matrix that has the orthogonal property. The purpose of the proposed orthogonal encoding technique is to improve the security of DRPE using the same key at the cost of a little complexity. The proposed orthogonal encoder consists of simple linear operations, so that it is easy to implement. We also provide the simulation results in order to show the effects of the proposed orthogonal encoding technique.

• 아동학회지
• /
• 제9권2호
• /
• pp.119-132
• /
• 1988

The purpose of the present study was to investigate the age-related and encoding-, or retrieval- conditions-related differences in recall and to assess any possible interaction between encoding and retrieval conditions. 108 first and fifth grade children and college adults were presented a 30 item set of pictures for recall it a 2-trial study-test procedure. The data were analyzed in 3(age) x 3(encoding condition) x 3(retrieval condition) x 2(trials) mixed analyses of variance with repeated measures on the last factor. The results indicated the age-related differences in recall and encoding conditions-related differences in recall in the fifth-graders and college adults. Also, the first and fifth grade children's recall was influenced by retrieval conditions. The fifth graders' recall was a function of the interaction of encoding and retrieval conditions.

• ETRI Journal
• /
• 제33권1호
• /
• pp.140-143
• /
• 2011

Recent test data compression techniques raise concerns regarding power dissipation and compression efficiency. This letter proposes a new test data compression scheme, twin symbol encoding, that supports block division skills that can reduce hardware overhead. Our experimental results show that the proposed technique achieves both a high compression ratio and low-power dissipation. Therefore, the proposed scheme is an attractive solution for efficient test data compression.

• 대한자기공명의과학회:학술대회논문집
• /
• 대한자기공명의과학회 2003년도 제8차 학술대회 초록집
• /
• pp.71-71
• /
• 2003

For fast MRI, the number of phase encoding steps has to be reduced. However, the reconstructed image is aliased if the phase encoding steps don't satisfy Nyquist sampling theory. SENSE is used in order to eliminate the aliasing effect as well as to reduce imaging time. SENSE is a linear algebraic technique applied to the multiple receiver data. In this study, we implement a tool to reconstruct the original image (SENSE image) with Sensitivity Encoding (SENSE)

• ETRI Journal
• /
• 제26권2호
• /
• pp.122-135
• /
• 2004

Although frame-based MPEG-4 video services have been successfully deployed since 2000, MPEG-4 video coding is now facing great competition in becoming a dominant player in the market. Object-based coding is one of the key functionalities of MPEG-4 video coding. Real-time object-based video encoding is also important for multimedia broadcasting for the near future. Object-based video services using MPEG-4 have not yet made a successful debut due to several reasons. One of the critical problems is the coding complexity of object-based video coding over frame-based video coding. Since a video object is described with an arbitrary shape, the bitstream contains not only motion and texture data but also shape data. This has introduced additional complexity to the decoder side as well as to the encoder side. In this paper, we have analyzed the current MPEG-4 video encoding tools and proposed efficient coding technologies that reduce the complexity of the encoder. Using the proposed coding schemes, we have obtained a 56 percent reduction in shape-coding complexity over the MPEG-4 video reference software (Microsoft version, 2000 edition).