• ETRI Journal
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• 제26권5호
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• pp.443-451
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• 2004

Since the publication of Alamouti's famous space-time block code, various quasi-orthogonal space-time block codes (QSTBC) for multi-input multi-output (MIMO) fading channels for more than two transmit antennas have been proposed. It has been shown that these codes cannot achieve full diversity at full rate. In this paper, we present a simple feedback scheme for rich scattering (flat Rayleigh fading) MIMO channels that improves the coding gain and diversity of a QSTBC for 2$^n$ (n=3, 4, ${\cdots}$) transmit antennas. The relevant channel state information is sent back from the receiver to the transmitter quantized to one or two bits per code block. In this way, signal transmission with an improved coding gain and diversity near to the maximum diversity order is achieved. Such high diversity can be exploited with either a maximum-likelihood receiver or low-complexity zero-forcing receiver.

• Earthquakes and Structures
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• 제3권3_4호
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• pp.473-494
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• 2012

The capacity of pipelines to resist collapse under external pressure and bending moment is a major aspect of deepwater pipeline design. Existing design codes present interaction equations that quantify pipeline capacities under such loadings, although reasonably accurate, are based on empirical data fitting of the bending strain, and assumed simplistic interaction with external pressure collapse. The rational model for collapse of deepwater pipelines, which are relatively thick with a diameter-to-thickness ratio less than 40, provides a unique theoretical basis since it is derived from first principles such as force equilibrium and compatibility equations. This paper presents the rational model methodology and compares predicted results and recently published full scale experimental data on the subject. Predictive capabilities of the rational model are shown to be excellent. The methodology is extended for the problem of pipeline collapse under point load, longitudinal bending and external pressure. Due to its rational derivation and excellent prediction capabilities, it is recommended that design codes adopt the rational model methodology.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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• pp.142-147
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• 1996

The analytic function expansion nodal (AFEN) method has been successfully applied to two-group neutron diffusion problems. In this paper, the AFEN method is extended to solve general multigroup equations for any type of geometries. Also, a suite of new nodal codes based on the extended AFEN theory is developed for hexagonal-z geometry and applied to several benchmark problems. Numerical results obtained attest to their accuracy and applicability to practical problems.

• Structural Engineering and Mechanics
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• 제87권3호
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• pp.243-254
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• 2023

Engineering structures usually suffer from cracks. The crack geometry has an influence on the structural mechanical properties and subsequent crack propagations. However, as an extensively utilized method in fracture analysis, the extended finite element method provided by Abaqus fails to output the specific location and dimensions of fractures. In this study, a technique to capture the crack geometry is proposed. The technique is based on the invariant level set method (I-LSM), which can avoid updating the level set function during crack development. The solution is achieved by an open-source plug-in programmed by Python. Three examples were performed to verify the effectiveness and robustness of the program. The result shows that the developed program can accurately output the crack geometry in both the 2D and 3D models. The open-source plug-in codes are included as supplementary material.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제6권3호
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• pp.329-338
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• 2000

CHILL 언어는 전전자 교환기 및 통신 시스템용 소프트웨어 개발에 사용되어왔다. ETRI CHILL-96 언어는 객체지향성, 병행성, 포괄적 타입과 같은 특성을 가지고 CHILL 언어를 확장한 것이다. 본 논문에서는 ETRI CHILL-96 컴파일러의 설계 및 구현과 관련된 몇 가지 기술적 주제들에 대해 다룬다. 재명명 변환 규칙들과 함수 재구성 기술들은 이름 충돌의 방지와 풍부한 디버깅 정보의 생성을 위해 사용되었다. 이러한 새로운 확장된 기능들은 확장된 CHILL 중간 코드로 컴파일 및 변환되는 단계에 전처리 되어진다. 이러한 컴파일 기술들은 ETRI CHILL-96언어가 기존의 CHILL 언어에 의해 개발된 소프트웨어들과 호환성을 유지할 수 있게 해 준다.

• The Journal of the Acoustical Society of Korea
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• 제20권4E호
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• pp.3-16
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• 2001

An ASCII encoding of Korean has been developed for extended phonetic transcription of the Speech Assessment Methods Phonetic Alphabet (SAMPA). SAMPA is a machine-readable phonetic alphabet used for multilingual computing. It has been developed since 1987 and extended to more than twenty languages. The motivating factor for creating Korean SAMPA (K-SAMPA) is to label Korean speech for a multilingual corpus or to transcribe native language (Ll) interfered pronunciation of a second language learner for bilingual education. Korean SAMPA represents each Korean allophone with a particular SAMPA symbol. Sounds that closely resemble it are represented by the same symbol, regardless of the language they are uttered in. Each of its symbols represents a speech sound that is spectrally and temporally so distinct as to be perceptually different when the components are heard in isolation. Each type of sound has a separate IPA-like designation. Korean SAMPA is superior to other transcription systems with similar objectives. It describes better the cross-linguistic sound quality of Korean than the official Romanization system, proclaimed by the Korean government in July 2000, because it uses an internationally shared phonetic alphabet. It is also phonetically more accurate than the official Romanization in that it dispenses with orthographic adjustments. It is also more convenient for computing than the International Phonetic Alphabet (IPA) because it consists of the symbols on a standard keyboard. This paper demonstrates how the Korean SAMPA can express allophonic details and prosodic features by adopting the transcription conventions of the extended SAMPA (X-SAMPA) and the prosodic SAMPA(SAMPROSA).

• 전자공학회논문지
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• 제53권4호
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• pp.48-58
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• 2016

본 논문은 GF(64) (160,80) 정규 (2,4) 비이진 LDPC 코드 복호기를 위한 높은 처리량의 병렬 아키텍처를 제안한다. 복호기의 복잡도를 낮추기 위해 체크 노드와 변수 노드의 차수가 작은 코드를 사용하며 뛰어난 에러 정정 성능을 위해 높은 위수의 유한체에서 정의된 코드를 사용한다. 본 논문은 Fully-parallel 아키텍처를 설계하고 체크 노드와 변수 노드를 interleaving하여 복호기의 데이터 처리량을 향상시켰다. 또한 체크 노드의 초기화 지연을 단축시킬 수 있는 조기 분류 기법을 제안하여 데이터 처리량을 추가로 향상시켰다. 제안된 복호기는 1 iteration에 37사이클이 소요되며 625MHz 동작주파수에서 1402Mbps의 데이터 처리량을 갖는다.

• 패션비즈니스
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• 제14권5호
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• pp.78-92
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• 2010

The culture phenomenon, which the desire of self expression is noticeable and the diversity of gender identity is widely accepted, simply makes a difference in the lifestyle of one human being rather than the dichotomous classification of male and female. Now, the delicate and aesthetic sensitivity classified as the feminine characteristics is no longer the exclusive property of female and this refers to substituting it as a social gender from the concept of biological sex. This phenomenon has influenced on the male culture and is creating various codes according to the cultural gender extended from the gender as a social role. Also, the transition into the western lifestyle has extended the aesthetic emotion to accommodate new codes from the diversification and globalization of lifestyle. The mansumer power, which does not care too much about the money for the emotionally attached items, has enabled various fashion styles. After analyzing the diversified clothing behavior conducted by these people in connection with the social phenomenon, First, this shows the phenomenon of emotional value pursuit that finds pleasure over the clothing as the item of augmented reality is added to the concept of play, in which the real space referred to as garment and virtual space of playing the rock, paper and scissors game meet together within the augmented reality. Second, the convergence concept has enabled the coordination of new style by obscuring the area of design concept and this refers to the changes in design from the development of new items and transformation into double-style details. Third, the divergence that intensively provides specific use/convenience and specialized value shows a change in the fashion market from the phenomenon that admits various gene rations of culture and specifically, takes differently about the recognition of middle-aged males. Fourth, the variety seeking tendency receives attention as the value of future design together with the phenomenon of discriminative value pursuit. In the male fashion, it is linked to the collaboration with the design area and this tells that the fashion with the narcissistic cross-dressing and motto of neutral gender without being sided to male/female is rising.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권2호
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• pp.658-675
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• 2022

This paper presents a fast-simplified successive cancellation (SC) flipping (Fast-SSC-Flip) decoding algorithm for polar code. Firstly, by researching the probability distribution of the number of error bits in a node caused by channel noise in simplified-SC (SSC) decoder, a measurement criterion of node reliability is proposed. Under the guidance of the criterion, the most unreliable nodes are firstly located, then the unreliable bits are selected for flipping, so as to realize Fast-SSC-Flip decoding algorithm based on node reliability (NR-Fast-SSC-Flip). Secondly, we extended the proposed NR-Fast-SSC-Flip to multiple node (NR-Fast-SSC-Flip-ω) by considering dynamic update to measure node reliability, where ω is the order of flip-nodes set. The extended algorithm can correct the error bits in multiple nodes, and get good performance at medium and high signal-to-noise (SNR) region. Simulation results show that the proposed NR-Fast-SSC-Flip decoder can obtain 0.27dB and 0.17dB gains, respectively, compared with the traditional Fast-SSC-Flip [14] and the newly proposed two-bit-flipping Fast-SSC (Fast-SSC-2Flip-E2) [18] under the same conditions. Compared with the newly proposed partitioned Fast-SSC-Flip (PA-Fast-SSC-Flip) (s=4) [18], the proposed NR-Fast-SSC-Flip-ω (ω=2) decoder can obtain about 0.21dB gain, and the FER performance exceeds the cyclic-redundancy-check (CRC) aided SC-list (CRC-SCL) decoder (L=4).

• 한국전자거래학회지
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• 제12권3호
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• pp.97-106
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• 2007

시맨틱 웹을 가능하게 해주는 핵심 기술은 온톨로지이다. 표준 언어로 자리잡은 OWL 웹 온톨로지 언어로 도메인을 직접 표현하기 위해서는 전문적인 기술이 요구된다. 따라서, 전자카탈로그 도메인 컨셉의 기초적인 관계들을 분석한 경험을 바탕으로 하여, 상품 도메인을 위한 OWL 코드를 자동적으로 생성해내는 시각적 상품정보 모델링 에디터인 PROMOD를 개발하였다. 특히, 개념모델링을 위해 상품 도메인에 특화된 모델링 요소들이 추가된 EER을 사용하였다. 본 논문에서는 EER 모델에서 OWL 코드로의 변환 방법과 PROMOD의 설계 및 구현을 보인다. 또한, 필드에서 이 모델링 에디터의 유용성을 시현하기 위한 시나리오를 제공한다.