• 한국통신학회논문지
• /
• 제33권5A호
• /
• pp.487-493
• /
• 2008

In this paper, we consider coded layered space-time architecture in MIMO-OFDM channels. Vertical Bell Lab Layered Space-Time(V-BLAST) scheme employing ordered successive interference cancellation(OSIC) algorithm provides very high spectral efficiency with low computational complexity. However, the error propagation is a major drawback constraining the overall performance of the V-BLAST system significantly. Based on this problem, we derive an improved detector using soft bit log-likelihood ratio(LLR) value. Simulation results show that the proposed detector outperforms the conventional V-BLAST scheme under spatially uncorrelated as well as correlated fading channels.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 2007년도 한국우주과학회보 제16권2호
• /
• pp.129-134
• /
• 2007

최근 정보의 양이 폭발적으로 증가하고 있는 가운데 누적된 대량의 정보에 대하여 수준, 흐름, 동향, 매핑 등의 효율적 정보분석체계가 매우 중요해지고 있다. 이 연구는 지난 30년간 위성항법 기술분야의 SCIE 논문 분석을 통하여 향후 연구개발 전략을 제안하고 있는 바, 구체적으로 국가간, 연구기관간, 연구자간의 네트워크와 중심성을 분석하고, 논문지도를 통하여 미래 기술확보에 대한 기회포착 및 선점의 전략을 제시하고 있다.

• 전기학회논문지
• /
• 제59권2호
• /
• pp.436-444
• /
• 2010

In this study, we introduce and discuss a concept of a granular-oriented radial basis function neural networks (GRBF NNs). In contrast to the typical architectures encountered in radial basis function neural networks(RBF NNs), our main objective is to develop a design strategy of GRBF NNs as follows : (a) The architecture of the network is fully reflective of the structure encountered in the training data which are granulated with the aid of clustering techniques. More specifically, the output space is granulated with use of K-Means clustering while the information granules in the multidimensional input space are formed by using a so-called context-based Fuzzy C-Means which takes into account the structure being already formed in the output space, (b) The innovative development facet of the network involves a dynamic reduction of dimensionality of the input space in which the information granules are formed in the subspace of the overall input space which is formed by selecting a suitable subset of input variables so that the this subspace retains the structure of the entire space. As this search is of combinatorial character, we use the technique of genetic optimization to determine the optimal input subspaces. A series of numeric studies exploiting some nonlinear process data and a dataset coming from the machine learning repository provide a detailed insight into the nature of the algorithm and its parameters as well as offer some comparative analysis.

• Spatial Information Research
• /
• 제23권1호
• /
• pp.69-77
• /
• 2015

본 연구는 1998년부터 2013년까지 지리공간정보와 관련된 연구 논문에 대해 키워드 네트워크 분석 기법을 적용하여 분석하고 글로벌 차원에서 지리공간정보 연구의 흐름을 도출하는데 목적이 있다. 이를 위해 Web of Science 학술 자료 검색 엔진을 이용하여 지리공간정보와 관련된 논문과 주요 키워드를 추출하였다. 그리고 추출된 키워드를 이용해 키워드 네트워크 자료를 구축하고 시기별 키워드의 연결중심성과 매개중심성, 근접중심성을 분석하였다. 그 결과 다양한 분야에서 지리공간정보가 활용되어 왔음을 확인할 수 있었고 관련된 기술의 연구 동향을 계량적으로 파악할 수 있었다. 이러한 연구 결과는 지리공간정보에 대한 정책과 연구 개발 계획을 과학적으로 수립하는데 활용될 수 있을 것으로 판단된다.

• 한국실내디자인학회논문집
• /
• 제20권5호
• /
• pp.236-244
• /
• 2011

As the digital information infrastructure is established for the public library system in the contemporary age, expectations and demands surrounding the public library system are growing rapidly as the place of exchange and enjoyment of information and culture, and as the place of life-long learning. In addition, a new kind of information & culture services are needed to meet the demands of contemporary men and women, who are exploring information as the information environment undergoes rapid changes - from increase in the volume of digital publications, to increase in the usefulness of online information resources, to strides made in the media industry. The public library will continue to play its role and function by providing to all users all available information, whether it's available online or offline, whether it's in a physical format or in a digital format. As such, design and management of a space appropriate as a new information environment are needed. It is deemed that an information infrastructure for Daegu that can improve the quality of life in the region and can increase user accessibility to information in this information age is needed, as well as reorganization of the pertinent environment. Therefore more public libraries have to be built in Daegu as a necessity, and it is urgently needed that the information services be expanded through an organic linkage between local libraries such as between the central library and the branch libraries. This paper aims to provide basic data for building of public libraries in Daegu. To establish an information infrastructure for Daegu, a direction is given for the establishment of a local network of public libraries and ways for improvement are explored. This paper is significant in that, first, it helps in the planning of a local network of public libraries, which plays a crucial role in improving accessibility to information as well as the level of their use; and second, it helps in setting up guidelines for spatial configuration of the user space. As for the method, quantitative review of the information environment is to be done by analyzing the present situation of the public library network in Daegu from the perspectives of region, facility, and space, in order to present a method of user-centered spatial configuration that meets the changes in social roles and forms of information in the contemporary society.

• Journal of Electrical Engineering and Technology
• /
• 제13권4호
• /
• pp.1724-1731
• /
• 2018

The conventional polynomial neural network (PNN) is a classical flexible neural structure and self-organizing network, however it is not free from the limitation of overfitting problem. In this study, we propose a space search-optimized polynomial neural network (ssPNN) structure to alleviate this problem. Ranking selection is realized by means of ranking selection-based performance index (RS_PI) which is combined with conventional performance index (PI) and coefficients based performance index (CPI) (viz. the sum of squared coefficient). Unlike the conventional PNN, L2-norm regularization method for estimating the polynomial coefficients is also used when designing the ssPNN. Furthermore, space search optimization (SSO) is exploited here to optimize the parameters of ssPNN (viz. the number of input variables, which variables will be selected as input variables, and the type of polynomial). Experimental results show that the proposed ranking selection-based polynomial neural network gives rise to better performance in comparison with the neuron fuzzy models reported in the literatures.

• 제어로봇시스템학회논문지
• /
• 제11권12호
• /
• pp.984-990
• /
• 2005

The aim of this paper is to investigate a control framework for mobile robots, operating in shared environment with humans. The Intelligent Space (iSpace) can sense the whole space and evaluate the situations in the space by distributing sensors. The mobile agents serve the inhabitants in the space utilizes the evaluated information by iSpace. The iSpace evaluates the situations in the space and learns the walking behavior of the inhabitants. The human intelligence manifests in the space as a behavior, as a response to the situation in the space. The iSpace learns the behavior and applies to mobile agent motion planning and control. This paper introduces the application of fuzzy-neural network to describe the obstacle avoidance behavior teamed from humans. Simulation results are introduced to demonstrate the efficiency of this method.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2016년도 추계학술대회
• /
• pp.715-718
• /
• 2016

우주 비행체의 온보드(on-board) 데이터 처리를 위해 고안된 스페이스와이어(SpaceWire)에는 네트워크의 시각 동기화를 위한 타임코드(time-code)가 정의되어있다. 타임코드가 네트워크를 통하여 전송되는 과정에서 전송 지연 및 지터(jitter)가 발생하며 이것은 시각 동기화 오차의 주요 원인이 된다. 본 논문은 스페이스와이어 표준에 정의되어 있는 타임코드를 확장하여 스페이스와이어 네트워크의 시각 동기화 오차를 줄이는 방안을 제안한다. 제안된 방안은 타임코드의 전송 지터에 따른 오차를 제거하고 타임코드가 링크를 거칠 때마다 발생하는 전송 지연을 제거할 수 있다. 그리고 그 효과는 OMNeT++을 이용하여 개발된 스페이스와이어 네트워크 시뮬레이션 환경을 이용하여 검증한다.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2007년도 추계종합학술대회
• /
• pp.950-953
• /
• 2007

본 논문에서는 인간과 환경사이의 물리적 또는 심리적 인터액션을 통한 인간중심의 적절한 서비스를 제공하는 공간지능화(iSpace: Intelligent Space) 구현하고자 네트웍 센서 인식공간을 소개하고 있다. 영상 데이터 처리 및 정보 네트웍 기능을 갖는 다수의 컬러 CCD 카메라를 iSpace 공간에 분산 배치하였다. iSpace내의 정보획득을 위한 네트웍 센서를 분산 지능형 네트웍 디바이스(DIND: Distributed Intelligent Network Devices)라고 명명하고 있으며, 각 DIND는 일종의 클라이언트 역할을 수행하도록 하였으며, DIND는 카메라 센서를 이용하는 이른바 카메라 네트워크를 구성한 것으로 이를 통해 실내 환경을 인식하고 모델링 하며 공간 내 거주자의 의도를 인식하기 위한 시스템을 구축하였다.

• 한국실내디자인학회논문집
• /
• 제32호
• /
• pp.64-71
• /
• 2002

Today, term of ‘industrial society’means the totally changing society by new technical innovation through the Industrial Revolution begun in England at the mid-nineteenth century and it made social structure centering agricultural culture change with industrial culture with expansion of goods by the massive production. Information working area has to bo a space not just for improving business efficiency in industrial society but for developing efficiency in working in harmony with the information and structural aspects based on computer and communication technology. There are two kinds of environmental elements of working space : the tangible ones are the area and the structure of working space, lights, network, layout and information machines in office, the intangible ones are a feeling of satisfaction of management and arrangement of office information machines capability of information delivery, common ownership of documents and their files, the security and connection between office workers, and harmony. According to the wave of information begun from the late twentieth century, structural layout of working area has become various by the working type through network of new developed information communication machines. But it is hard to apply them in actually.