• Title/Summary/Keyword: Unit Vector

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Recombinant Adenoviral Vector Containing Tumor-Specific L-Plastin Promoter Fused to Cytosine Deaminase Gene as a Transcription Unit: Generation and Functional Test

  • Chung, In-Jae;Deisseroth, Albert-B.
    • Archives of Pharmacal Research
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    • 제27권6호
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    • pp.633-639
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    • 2004
  • The expression of therapeutic transgenes in recombinant adenoviral vectors is a major cause of toxicity in dividing cancer cells as well as non dividing normal cells. To solve the problem of toxicity to normal cells, we have reported on a recombinant adenoviral vector system (AdLP-) in which the expression of the transgene is directed by the tumor-specific L-plastin promoter (LP) (Chung et al., 1999). The object of this study was to generate a recombinant adenoviral vector system which would generate tumor cell specific expression of cytosine deaminase (CD) gene. We report the construction of a replication-incompetent adenoviral vector in which CD is driven by the L-plastin promoter (AdLPCD). Infection of 293 cells by AdLPCD generated the functional CD protein as measured by HPLC analysis for the conversion of 5-Fluorocy-tosine (5-FC) to 5-Fluorouracil (5-FU). HPLC analysis in conjunction with counting radioactivity for [6-$^3$H]-5FC and [6-$^3$H]-5FU demonstrated vector dose-dependent conversion of 5-FC to 5-FU in AdLPCD infected ovarian cancer cells. The results from present and previous studies(Peng et al., 2001; Akbulut et al., 2003) suggest that the use of the AdLPCD/5-FC system may be of value in the treatment of cancer including microscopic ovarian cancer in the peritoneal cavity.

손실이 있는 Left-Handed 전송선로를 이용한 감쇠기와 벡터 변조기 응용 (Attenuator using Lossy Left-Handed Transmission Line and Vector Modulator Application)

  • 김승환;김일규;김영;윤영철
    • 한국항행학회논문지
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    • 제13권3호
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    • pp.399-405
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    • 2009
  • 본 논문은 메타 재질 구조를 바탕으로 한 가변 감쇠기와 그 응용에 대하여 기술 하였다. 손실이 존재하는 전송선로를 이용한 감쇠기 단위 셀은 CRLH(Composite Right/Left Handed) 전송선로와 다이오드 바이어스 전압에 따라서 내부 저항값의 변화에 따라서 손실을 제어할 수 있는 PIN다이오드로 구성되어 있다. 또한, 내부의 초기 삽입 손실을 줄이기 위해서 두 개의 PIN 다이오드를 병렬로 연결하였다. 이 감쇠기는 감쇠기 단위 셀 숫자를 증가시킴으로서 감쇠량을 증가시킬 수 있는 주기적 구조로 설계되었다. 단위 셀의 전기적 특성은 주파수 1.5 GHz ~ 2.5 GHz에서 10dB의 감쇠량과 최대 15o의 위상변화를 확인하였다. 이러한 특성의 감쇠기를 직렬로 연결하여 벡터 변조기에 응용하였다.

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Adaptive Speech Streaming Based on Packet Loss Prediction Using Support Vector Machine for Software-Based Multipoint Control Unit over IP Networks

  • Kang, Jin Ah;Han, Mikyong;Jang, Jong-Hyun;Kim, Hong Kook
    • ETRI Journal
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    • 제38권6호
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    • pp.1064-1073
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    • 2016
  • An adaptive speech streaming method to improve the perceived speech quality of a software-based multipoint control unit (SW-based MCU) over IP networks is proposed. First, the proposed method predicts whether the speech packet to be transmitted is lost. To this end, the proposed method learns the pattern of packet losses in the IP network, and then predicts the loss of the packet to be transmitted over that IP network. The proposed method classifies the speech signal into different classes of silence, unvoiced, speech onset, or voiced frame. Based on the results of packet loss prediction and speech classification, the proposed method determines the proper amount and bitrate of redundant speech data (RSD) that are sent with primary speech data (PSD) in order to assist the speech decoder to restore the speech signals of lost packets. Specifically, when a packet is predicted to be lost, the amount and bitrate of the RSD must be increased through a reduction in the bitrate of the PSD. The effectiveness of the proposed method for learning the packet loss pattern and assigning a different speech coding rate is then demonstrated using a support vector machine and adaptive multirate-narrowband, respectively. The results show that as compared with conventional methods that restore lost speech signals, the proposed method remarkably improves the perceived speech quality of an SW-based MCU under various packet loss conditions in an IP network.

Testing for a unit root in an AR(p) signal observed with MA(q) noise when the MA parameters are unknown

  • Jeong, Dong-bin;Sahadeb Sarkar
    • Journal of the Korean Statistical Society
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    • 제27권2호
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    • pp.165-187
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    • 1998
  • Shin and Sarkar (1993, 1994) studied the problem of testing for a unit root in an AR(p) signal observed with MA(q) noise when the MA parameters are known. In this paper we consider the case when the MA parameters are unknown and to be estimated. Test statistics are defined using unit root parameter estimates based on three different estimation methods of Hannan and Rissanen (1982), Kohn (1979) and Shin and Sarkar (1995). An AR(p) process contaminated by MA(q) noise is a .estricted ARMA model, for which Shin and Sarkar (1995) derived an easy-to-compute Newton- Raphson estimator The two-stage estimation p.ocedu.e of Hannan and Rissanen (1982) is used to compute initial parameter estimates in implementing the iterative estimation methods of both Shin and Sarkar (1995) and Kohn (1979). In a simulation study we compare the relative performance of these unit root tests with respect to both size and power for p=q=1.

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Risk of Recrudescence of Lymphatic Filariasis after Post-MDA Surveillance in Brugia malayi Endemic Belitung District, Indonesia

  • Santoso, Santoso;Yahya, Yahya;Supranelfy, Yanelza;Suryaningtyas, Nungki Hapsari;Taviv, Yulian;Yenni, Aprioza;Arisanti, Maya;Mayasari, Rika;Mahdalena, Vivin;Nurmaliani, Rizki;Marini, Marini;Krishnamoorthy, K.;Pangaribuan, Helena Ullyartha
    • Parasites, Hosts and Diseases
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    • 제58권6호
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    • pp.627-634
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    • 2020
  • Belitung district in Bangka-Belitung Province, Indonesia with a population of 0.27 million is endemic for Brugia malayi and 5 rounds of mass drug administration (MDA) were completed by 2010. Based on the results of 3 transmission assessment surveys (TAS), the district is declared as achieving elimination of lymphatic filariasis (LF) in 2017. The findings of an independent survey conducted by the National Institute of Health Research and Development (NIHRD) in the same year showed microfilaria (Mf) prevalence of 1.3% in this district. In 2019, NIHRD conducted microfilaria survey in 2 villages in Belitung district. Screening of 311 and 360 individuals in Lasar and Suak Gual villages showed Mf prevalence of 5.1% and 2.2% with mean Mf density of 120 and 354 mf/ml in the respective villages. Mf prevalence was significantly higher among farmers and fishermen compared to others and the gender specific difference was not significant. The results of a questionnaire based interview showed that 62.4% of the respondents reported to have participated in MDA in Lasar while it was 57.7% in Suak Gual village. About 42% of the Mf positive cases did not participate in MDA. Environmental surveys identified many swampy areas supporting the breeding of Mansonia vector species. Persistence of infection is evident and in the event of successful TAS3 it is necessary to monitor the situation and plan for focal MDA. Appropriate surveillance strategies including xenomonitoring in post-MDA situations need to be developed to prevent resurgence of infection. Possible role of animal reservoirs is discussed.

자산가격의 결정요인에 대한 실증분석 : 미국사례를 중심으로 (A Study on Determinants of Asset Price : Focused on USA)

  • 박형규;정동빈
    • 산경연구논집
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    • 제9권5호
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    • pp.63-72
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    • 2018
  • Purpose - This work analyzes, in detail, the specification of vector error correction model (VECM) and thus examines the relationships and impact among seven economic variables for USA - balance on current account (BCA), index of stock (STOCK), gross domestic product (GDP), housing price indices (HOUSING), a measure of the money supply that includes total currency as well as large time deposits, institutional money market funds, short-term repurchase agreements and other larger liquid assets (M3), real rate of interest (IR_REAL) and household credits (LOAN). In particular, we search for the main explanatory variables that have an effect on stock and real estate market, respectively and investigate the causal and dynamic associations between them. Research design, data, and methodology - We perform the time series vector error correction model to infer the dynamic relationships among seven variables above. This work employs the conventional augmented Dickey-Fuller (ADF) and Phillips-Perron (PP) unit root techniques to test for stationarity among seven variables under consideration, and Johansen cointegration test to specify the order or the number of cointegration relationship. Granger causality test is exploited to inspect for causal relationship and, at the same time, impulse response function and variance decomposition analysis are checked for both short-run and long-run association among the seven variables by EViews 9.0. The underlying model was analyzed by using 108 realizations from Q1 1990 to Q4 2016 for USA. Results - The results show that all the seven variables for USA have one unit root and they are cointegrated with at most five and three cointegrating equation for USA. The vector error correction model expresses a long-run relationship among variables. Both IR_REAL and M3 may influence real estate market, and GDP does stock market in USA. On the other hand, GDP, IR_REAL, M3, STOCK and LOAN may be considered as causal factors to affect real estate market. Conclusions - The findings indicate that both stock market and real estate market can be modelled as vector error correction specification for USA. In addition, we can detect causal relationships among variables and compare dynamic differences between countries in terms of stock market and real estate market.

방사선 진행방향을 이용한 원격치료장치의 기계적 정확성 평가방법 (A Method for Evaluation of Mechanical Accuracy of a Teletherapy Machine Using Beam Directions)

  • 강위생
    • 한국의학물리학회지:의학물리
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    • 제7권1호
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    • pp.53-64
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    • 1996
  • 목적 : 별모양무늬를 이용하여 원격 방사선치료기의 회전축의 정확성을 평가할 때 방사선의 진행방향을 고려해야 하는 이론적 근거와 방법을 개발하고, 방사선의 진행방향이 기록되지 않는 경우 길이 방향의 비대칭 조사면을 이용하여 흉내내는 방법을 개발하는 것이다. 방법 : 갠트리 회전축의 기계적 정확성을 평가하기 위해 방사선의 진행방향을 고려하였다. 좁은 조사면에 의해 별모양무늬를 만들어 회전축이라고 어림되는 교점에서 l0cm 떨어진 위치의 측방선량분포를 필름농도계로 측정하여 선축의 좌표를 구하고 하나의 선축에 있는 한 쌍의 좌표를 이용하여 선축의 식을 구한다. 선축과 일치하는 방사선 진행방향의 단위벡터 equation omitted를 구하고 가정된 회전축의 좌표에서 각 선축으로 향하는 벡터 equation omitted와 equation omitted의 벡터곱 equation omitted$\times$equation omitted을 구하여 평균을 취하고 평균에 대한 벡터곱의 최소자승법을 적용하여 회전축의 좌표를 구한다. 그 때 벡터곱의 최대치의 절대값이 구하는 회전축의 정확도이다. 방사선의 진행방향을 고려할 수 없는 콜리메이터와 치료대에 대해서는 진행방향에 대응하는 것으로 긴 방향이 비대칭인 조사면을 이용하였다. 결과 : 동일한 별모양 무늬에 대해 방사선의 진행방향을 고려할 때 회전축의 기계적 정확성이 진행방향을 무시할 때와 다르게 평가되었다. 결론 : 별모양 무늬를 이용하여 원격치료기의 기계적 정확성을 평가할 때는 방사선의 진행방향을 고려하거나 흉내내어 정량적으로 평가해야 한다.

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Out-of-Vocabulary 단어에 강건한 병렬 Tri-LSTM 문장 임베딩을 이용한 감정분석 (Sentiment Analysis using Robust Parallel Tri-LSTM Sentence Embedding in Out-of-Vocabulary Word)

  • 이현영;강승식
    • 스마트미디어저널
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    • 제10권1호
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    • pp.16-24
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    • 2021
  • word2vec 등 기존의 단어 임베딩 기법은 원시 말뭉치에 출현한 단어들만을 대상으로 각 단어를 다차원 실수 벡터 공간에 고정된 길이의 벡터로 표현하기 때문에 형태론적으로 풍부한 표현체계를 가진 언어에 대한 단어 임베딩 기법에서는 말뭉치에 출현하지 않은 단어들에 대한 단어 벡터를 표현할 때 OOV(out-of-vocabulary) 문제가 빈번하게 발생한다. 문장을 구성하는 단어 벡터들로부터 문장 벡터를 구성하는 문장 임베딩의 경우에도 OOV 단어가 포함되었을 때 문장 벡터를 정교하게 구성하지 못하는 문제점이 있다. 특히, 교착어인 한국어는 어휘형태소와 문법형태소가 결합되는 형태론적 특성 때문에 미등록어의 임베딩 기법은 성능 향상의 중요한 요인이다. 본 연구에서는 단어의 형태학적인 정보를 이용하는 방식을 문장 수준으로 확장하고 OOV 단어 문제에 강건한 병렬 Tri-LSTM 문장 임베딩을 제안한다. 한국어 감정 분석 말뭉치에 대해 성능 평가를 수행한 결과 한국어 문장 임베딩을 위한 임베딩 단위는 형태소 단위보다 문자 단위가 우수한 성능을 보였으며, 병렬 양방향 Tri-LSTM 문장 인코더는 86.17%의 감정 분석 정확도를 달성하였다.

EQUIVARIANT VECTOR BUNDLES OVER $S^1$

  • Kim, Sung-Sook
    • 대한수학회논문집
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    • 제9권2호
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    • pp.415-418
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    • 1994
  • Let G be a compact Lie group and let $S^1$ denote the unit circle in $R^2$ with the standard metric. Since every smooth compact Lie group action on $S^1$ is smoothly equivalent to a linear action (cf. [3J TH 2.0), we may think of $S^1$ with a smooth G-action as S(V) the unit circle of a real 2-dimensional orthogonal G-module V.(omitted)

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