• Entomological Research
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• 제48권5호
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• pp.390-399
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• 2018

In order to precisely assess gene expression levels, the suitable internal reference genes must be served to quantify real-time reverse transcription polymerase chain reaction (RT-qPCR) data. For armyworm, Mythimna separata, which reference genes are suitable for assessing the level of transcriptional expression of target genes have yet to be explored. In this study, eight common reference genes, including ${\beta}$-actin (${\beta}$-ACT), 18 s ribosomal (18S), 28S ribosomal (28S), glyceraldehyde-3-phosphate (GAPDH), elongation fator-alpha ($EF1{\alpha}$), TATA box binding protein (TBP), ribosomal protein L7 (RPL7), and alpha-tubulin (${\alpha}$-TUB) that in different developmental stages, tissues and insecticide treatments of M. separata were evaluated. To further explore whether these genes were suitable to serve as endogenous controls, three software-based approaches (geNorm, BestKeeper, and NormFinder), the delta Ct method, and one web-based comprehensive tool (RefFinder) were employed to analyze and rank the tested genes. The optimal number of reference genes was determined using the geNorm program, and the suitability of particular reference genes was empirically validated according to normalized HSP70, and MsepCYP321A10 gene expression data. We found that the most suitable reference genes for the different experimental conditions. For developmental stages, 28S/RPL7 were the optimal reference genes, both $RPL7/EF1{\alpha}$ were suitable for experiments of different tissues, whereas for insecticide treatments, $28S/{\alpha}-TUB$ were suitable for normalizations of expression data. In addition, $28S/{\alpha}-TUB$ were the suitable reference genes because they have the most stable expression among different developmental stages, tissues and insecticide treatments. Our work is the first report on reference gene selection in M. separata, and might serve as a precedent for future gene expression studies.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권4호
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• pp.165-172
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• 2006

In this paper we present a technique for detecting cross-reference points that allows improving watermark detect-ability. In general, Harris detector is commonly used for finding salient points. Harris detector is a kind of combined corner and edge detector which is based on neighboring image data distribution, therefore it has some limitation to find accurate salient points after watermark embedding or any kinds of digital attacks. The new method proposed in this paper used not data distribution but geometrical structure of a normalized image in order to avoid pointing error caused by the distortion of image data. After normalization, we constructed pre-specified number of virtual lines from top to bottom and left to right, and several of cross points were selected by a random key. These selected points specify almost same positions with the accuracy more than that of Harris detector after digital attacks. These points were arranged by a random key, and blocks centered in these points were formed. A reference watermark is formed by a block and embedded in the next block. Because same alteration is applied to the watermark generated and embedded blocks. the detect-ability of watermark is improved even after digital attacks.

• 전력전자학회논문지
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• 제7권5호
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• pp.413-418
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• 2002

본 연구는 관성의 변화에 견실한 피드포워드 적응 위치제어기를 제안한다. 제안된 피드포워드 적응 위치제어기는 PI 위치제어기에 피드포워드와 기준모델 적응제어기를 추가한 구조를 가진다. 제어기의 특징은 과도상태에서 적응제어기가 위치오차와 기준모델의 속도 정보를 이용하여 피드포워드 이득을 조정한다. 이것은 과도응답 특성을 향상시키고, 정상상태의 수렴 시간을 개선시킨다. 위치 오차에 속도의 정보를 받아들여 기존의 Pl 위치제어 및 기준모델 적응제어에 비하여 속응성이 우수하다. 그리고, 적응제어기에 규준화 함수를 사용하여 입력크기에 대해 출력신호가 일정한 응답특성을 가지도록 하였다. 시뮬레이션을 통하여 제안된 피드포워드 적응 위치제어기 동작의 타당성을 보였다.

• The Plant Pathology Journal
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• 제35권1호
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• pp.11-18
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• 2019

Gaeumannomyces graminis var. tritici is a soil borne pathogenic fungus associated with wheat roots. The accurate quantification of gene expression during the process of infection might be helpful to understand the pathogenic molecular mechanism. However, this method requires suitable reference genes for transcript normalization. In this study, nine candidate reference genes were chosen, and the specificity of the primers were investigated by melting curves of PCR products. The expression stability of these nine candidates was determined with three programs-geNorm, Norm Finder, and Best Keeper. $TUB{\beta}$ was identified as the most stable reference gene. Furthermore, the exopolygalacturonase gene (ExoPG) was selected to verify the reliability of $TUB{\beta}$ expression. The expression profile of ExoPG assessed using $TUB{\beta}$ agreed with the results of digital gene expression analysis by RNA-Seq. This study is the first systematic exploration of the optimal reference genes in the infection process of Gaeumannomyces graminis var. tritici.

• 한국음향학회지
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• 제24권5호
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• pp.255-261
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• 2005

화자들 사이의 워핑특성을 알아보기 위해 비정형 워핑함수를 도출하는 실험을 수행하였다. 이를 위해 모음의 MFCC와 LP 스펙트럼을 이용하여 화자별, 음소별 대표 스펙트럼을 선정한 다음 음소별 기준 스펙트럼을 선택하였다. 기준 스펙트럼과 대표 스펙트럼을 스펙트럼의 전체대역에서 DTW로 비교하여 화자별 워핑함수를 구한 다음, 이들을 clustering함으로써 비정형 워핑함수의 집합을 도출하였다. 이 함수집합에서 남성화자와 여성화자의 함수들이 각각 구간선형함수와 파워함수와 유사함을 관찰할 수 있었으며, 이를 근거로 이 함수들을 조합한 하이브리드 워핑함수집합을 정의하였다. 음소단위의 인식 실험을 통하여 새로 정의된 함수들의 인식률을 시험하였으며 두 함수집합 모두에서 개선된 인식률을 얻을 수 있었다.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2001년도 추계학술발표대회 논문집 제20권 2호
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• pp.97-103
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• 2001

초기 DTW(Dynamic Time Warping)를 이용한 화자인식 방법은 인식률이 시간이 지남에 따라 저하된다는 단점이 있었다[1][3][4]. 따라서 이를 보완하기 위한 새로운 알고리즘이 많이 제안되었다. 본 논문에서는 DTW방법을 이용한 화자 인식 시스템의 사용자 등록시기에 화자에 대한 불충분한 음성특징을 보충하고 시간이 지남에 따라 발생하는 오인식률의 증가를 줄이기 위해 사용자 등록시 기준패턴의 정규화를 수행하고 시스템 사용시 기준패턴을 변경하는 방법이다. 본 논문에서 사용된 핵심적인 알고리즘은 VQ(Vector Quantization)와 DTW 방법이다. 본 논문의 알고리즘을 이용한 모의 실험 결과 기존의 방법에 비해 $3.3\%$ 인식률 향상되어 $97.5\%$의 인식률을 얻을 수 있었다.

• 전기학회논문지
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• 제56권8호
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• pp.1484-1490
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• 2007

The Cross Reference Point(CRP) is a robust method for finding salient points in watermarking systems because it is based on the geometrical structure of a normalized image in order to avoid pointing error caused by digital attacks. After normalization of an image, the 100 CRPs are calculated. Next, the 100 blocks centered by CRPS are formed. These 100 blocks are arranged using a secrete key. Each boundary of 50 out of 100 blocks is surrounded by 8 blocks which are selected by the ordered number of a preceding block. This number is a seed of random number generator for selecting 8 out of 50 blocks. The search area of a center block is formed by a secrete key. The pixels of a center block are quantized to 10 levels by predefined thresholds. The watermarks are generated by the 50 quantized center blocks. These watermarks are embedded directly in the remaining 50 blocks. In other words, 50 out of 100 blocks are utilized to generate watermarks and the remaining 50 blocks are used to watermark embedding. Because the watermarks are generated in the given images, we can successfully detect watermarks after several digital attacks. The reason is that the blocks for the generation and detection of watermarks are equally affected by digital attacks except for the case of local distortion such as cropping.

• Animal Bioscience
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• 제35권12호
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• pp.1850-1859
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• 2022

Objective: The quantitative reverse transcription polymerase chain reaction (qPCR) is the most accurate and reliable technique for analysis of gene expression. Endogenous reference genes (RGs) have been used to normalize qPCR data, although their expression may vary in different tissues and experimental conditions. Verification of the stability of RGs in selected samples is a prerequisite for reliable results. Therefore, we attempted to identify the most stable RGs in the hypothalamic-pituitary-gonadal (HPG) axis in sows. Methods: The cycle threshold values of nine commonly used RGs (18S, HPRT1, GAPDH, RPL4, PPIA, B2M, YWHAZ, ACTB, and SDHA) from HPG axis-related tissues in the domestic sows in the different stages of estrus cycle were analyzed using two RG-finding programs, geNorm and Normfinder, to rank the stability of the pool of RGs. In addition, the effect of the most and least stable RGs was examined by normalization of the target gene, gonadotropin-releasing hormone (GnRH), in the hypothalamus. Results: PPIA, HPRT1, and YWHAZ were the most stable RGs in the HPG axis-related tissues in sows regardless of the stages of estrus cycle. In contrast, traditional RGs, including 18S and ACTB, were found to be the least stable under these experimental conditions. In particular, in the normalization of GnRH expression in the hypothalamus against several stable RGs, PPIA, HPRT1, and YWHAZ, could generate significant (p<0.05) elevation of GnRH in the preovulatory phase compared to the luteal phase, but the traditional RGs with the least stability (18S and ACTB) did not show a significant difference between groups. Conclusion: These results indicate the importance of verifying RG stability prior to commencing research and may contribute to experimental design in the field of animal reproductive physiology as reference data.

• 대한방사선치료학회지
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• 제14권1호
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• pp.79-84
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• 2002

1.목적 : 작고 불규칙한 모양의 전자선 조사면에서 선원의 출력에 영향을 미치는 요인은 선형가속기의 collimation system, insert block diameter, energy 등이다. 때문에 이러한 조사면의 선량계산으로 LBR을 이용할 수 있는데 LBR(lateral build-up ratio)이란 동일한 incident fluence와 profile에 대해 circular field와 broad field의 선량비로서 나타낼 수 있다. 얻어진 LBR data는 elementary pencil beam 모형을 근거해 깊이와 에너지에 따른 함수(${\sigma}$)로 표현할 수 있다. 여기에서 얻어진 수식을 기초로 해서 만들어진 factor값이 작고 부정형의 전자선 조사면의 선량계산 유용성을 알아보고자 한다. 2.재료 및 방법: 심부선량은 water phantom에서 ion chamber로 측정하였다. Cerrobend와 electron applicator 에 따른 incident fluence의 변화를 알아보기 위해 Chamber를 0.5mm깊이에 놓고 측정하였다. 그리고 에너지와 electron applicator 크기에 따라 insert block diameter를 2-15cm로 변화시키며 심부선량을 측정하였고 이 값을 0.5mm 깊이에서 normalization 하였다. 이렇게 normalization 한 그래프로부터 LBR과 함수 (${\sigma}$)를 얻어했다. 3.결과 : 0.5mm 깊이에서 normalization한 심부선량-그래프로부터 LBR data와 그로부터 얻어낸 (${\sigma}$)함수 값을 기초로 하여 elementary pencil beam 모형의 깊이에 빠른 선량변화의 수식을 얻어낼 수 있었다. 4.결론 : 부정형 전자선 조사면에 대해 MU당 심부선량은 작은 circular field에서 측정된 LBR값, reference applicator와 insert block diameter 에 따른 incident fluence factor 그리고 reference broad field에서의 심부선량등 세 가지 data로 부터 계산할 수 있다. 이 방법을 이용하면 어떤 모양의 전자선 조사면에 대해서도 심부선량의 계산에 유용하다고 할 수 있다.

• 한국동물생명공학회지
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• 제37권2호
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• pp.96-105
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• 2022

The ovary undergoes substantial physiological changes along with estrus phase to mediate negative/positive feedback to the upstream reproductive tissues and to play a role in producing a fertilizable oocyte in the developing follicles. However, the disorder of estrus cycle in female can lead to diseases, such as cystic ovary which is directly associated with decline of overall reproductive performance. In gene expression studies of ovaries, quantitative reverse transcription polymerase chain reaction (qPCR) assay has been widely applied. During this assay, although normalization of target genes against reference genes (RGs) has been indispensably conducted, the expression of RGs is also variable in each experimental condition which can result in false conclusion. Because the understanding for stable RG in porcine ovaries was still limited, we attempted to assess the stability of RGs from the pool of ten commonly used RGs (18S, B2M, PPIA, RPL4, SDHA, ACTB, GAPDH, HPRT1, YWHAZ, and TBP) in the porcine ovaries under different estrus phase (follicular and luteal phase) and cystic condition, using stable RG-finding programs (geNorm, Normfinder, and BestKeeper). The significant (p < 0.01) differences in Ct values of RGs in the porcine ovaries under different conditions were identified. In assessing the stability of RGs, three programs comprehensively agreed that TBP and YWHAZ were suitable RGs to study porcine ovaries under different conditions but ACTB and GAPDH were inappropriate RGs in this experimental condition. We hope that these results contribute to plan the experiment design in the field of reproductive physiology in pigs as reference data.