• Title/Summary/Keyword: subtraction

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Measurements and characterizations of cerenkov light in fiber-optic radiation sensor irradiated by high energy electron beam (고에너지 전자선 측정을 위한 광섬유 방사선 센서에서의 체렌코프 빛 측정 및 분석)

  • Jang, Kyoung-Won;Cho, Dong-Hyun;Jeong, Sun-Cheol;Jun, Jae-Hun;Lee, Bong-Soo;Kim, Sin;Cho, Hyo-Sung;Park, Sung-Yong;Shin, Dong-Ho
    • Journal of Sensor Science and Technology
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    • v.15 no.3
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    • pp.186-191
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    • 2006
  • In general, Cerenkov light is produced by a charged particle that passes through a medium with a velocity greater than that of visible light. Although the wavelength of Cerenkov light is very broad, the peak is in the almost visible range from 400 to 480 nm. Therefore, it always causes a problem to detect a real light signal that is generated in the scintillator on the fiber-optic sensor tip for dose measurements of high-energy electron beam. The objectives of this study are to measure, characterize and remove Cerenkov light generated in a fiber-optic radiation sensor tip to detect a real light signal from the scintillator. In this study, the intensity of Cerenkov light is measured and characterized as a function of incident angle of electron beam from a LINAC, and as a function of the energy of electron beam. As a measuring device, a photodiode-amplifier system is used, and a subtraction method using a background optical fiber is investigated to remove Cerenkov light.

Magma Differentiation and Mineral Accumulation of the Sangnae-ri Dolerite Sill in the Okchon Belt (옥천대내 상내리 조립현무암질 암상에서의 마그마 분화와 광물의 집적)

  • Ahn, Kun-Sang;Kim, Hee-Nam;Shin, In-Hyun
    • Economic and Environmental Geology
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    • v.26 no.3
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    • pp.363-370
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    • 1993
  • Various sizes of dolerite sills occur in the Mungyong area, one of well-exposed areas in Okchon belt. All of previous geochemical studies concluded that chemical variations of basic rocks, so-called Sangnae-ri amphibolite, result from the fractional crystallization. The second sill, which is a well differentiated one in the Sangnae-ri area, displays systematic compositional variation associated with gradual change of grain size in vertical sections. In order to clarify the chemical variation in the sill, whether chemical composition of each part of the sill is appropriately derived from the original liquid (represented by the average composition) by addition or subtraction of initial phenocystic minerals are tested(Iwamori program, 1989). According to the calculation, it is shown that major vertical chemical variation of the sill resulted from the accumulation of phenocrysts(olivine, clinopyrxoene, plagioclase, titanomagnetite) which already existed at the time of emplacement or formed just after the emplacement.

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Algebraic Reasoning Abilities of Elementary School Students and Early Algebra Instruction(1) (초등학생의 대수 추론 능력과 조기 대수(Early Algebra) 지도(1))

  • Lee, Hwa Young;Chang, Kyung Yoon
    • School Mathematics
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    • v.14 no.4
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    • pp.445-468
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    • 2012
  • This study is tried in order to link informal arithmetic reasoning to formal algebraic reasoning. In this study, we investigated elementary school student's non-formal algebraic reasoning used in algebraic problem solving. The result of we investigated algebraic reasoning of 839 students from grade 1 to 6 in two schools, Korea, we could recognize that they used various arithmetic reasoning and pre-formal algebraic reasoning which is the other than that is proposed in the text book in word problem solving related to the linear systems of equation. Reasoning strategies were diverse depending on structure of meaning and operational of problems. And we analyzed the cause of failure of reasoning in algebraic problem solving. Especially, 'quantitative reasoning', 'proportional reasoning' are turned into 'non-formal method of substitution' and 'non-formal method of addition and subtraction'. We discussed possibilities that we are able to connect these pre-formal algebraic reasoning to formal algebraic reasoning.

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Small Target Detection using Morphology and Gaussian Distance Function in Infrared Images (적외선 영상에서 모폴로지와 가우시안 거리함수를 이용한 소형표적 검출)

  • Park, Jun-Jae;Ahn, Sang-Ho;Kim, Jong-Ho;Kim, Sang-Kyoon
    • Journal of Korea Society of Industrial Information Systems
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    • v.17 no.4
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    • pp.61-70
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    • 2012
  • We propose a method that finds candidate targets based on morphology and detects a small target from them using modified gaussian distance function. The existing small target detection methods use predictive filters or morphology. The methods using predictive filters take long to approach least errors. The methods using morphology are weak at clutters and need to consider size of a small target when selecting size of structure elements. We propose a robust method for small target detection to complete the existing methods. First, the proposed method deletes clutters using a median filter. Next, it does closing and opening operation using various size of structure elements, and figures target candidate pixels with subtraction operation between the results of closing and opening operation. It detects an exact small target using a gaussian distance function from the candidates target areas. The proposed method is less sensitive to clutters, and shows a detection rate of 98%.

Identification of Differentially Expressed Genes in Human Small Cell Lung Carcinoma Using Subtractive Hybridization

  • Ahn Seung-Ju;Choi Jae-Kyoung;Joo Young Mi;Lee Min-A;Choi Pyung-Rak;Lee Yeong-Mi;Kim Myong-Shin;Kim So-Young;Jeon Eun-Hee;Min Byung-In;Kim Chong-Rak
    • Biomedical Science Letters
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    • v.10 no.3
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    • pp.195-202
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    • 2004
  • Lung cancer is a leading cause of cancer death worldwide; however, despite major advances in cancer treatment during the past two decades, the prognostic outcome of lung cancer patients has improved only minimally. This is largely due to the inadequacy of the traditional screening approach of diagnosis in lung cancer, which detects only well­established overt cancers and fails to identify precursor lesions in premalignant conditions of the bronchial tree. In recent years this situation has fundamentally changed with the identification of molecular abnormalities characteristic of premalignant changes; these concern tumour suppressor genes, loss of heterozygosity at crucial sites and activation of oncogenes. Basic knowledge at the molecular level has extremely important clinical implications with regard to early diagnosis, risk assessment and prevention, and therapeutic targets. In this study we used a 'cap-finder' subtractive hybridization method, 'long distance' polymerase chain reaction (PCR), streptavidin magnetic beads mediated subtraction, and spin column chromatography to detect differential expression genes of human small cell lung carcinoma. We have now isolated ninety two genes that expressed differentially in the human small cell lung carcinoma cells and analyzed of 12 clones with sequencing, nine cDNAs include tapasin (NGS-17) mRNA, BC200 alpha scRNA, chromosome 12q24 PAC RPCI3-462E2, protein phosphatase 1 (PPPICA), translocation protein 1 (TLOC1), ribosomal protein S24 (RPS24) mRNA, protein phosphatase (PPEF2), cathepsin Z, MDM2 gene and three novel genes. They may be oncogenesis­related proteins.

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THE SPECTRAL SHAPE MATCHING METHOD FOR THE ATMOSPHERIC CORRECTION OF LANDSAT IMAGERY IN SAEMANGEUM COASTAL AREA

  • Min Jee-Eun;Ryu Joo-Hyung;Shanmugam P.;Ahn Yu-Hwan;Lee Kyu-Sung
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.671-674
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    • 2005
  • Atmospheric correction over the ocean part is more important than that over the land because the signal from the ocean is very small about one tenth of that reflected from land. In this study, the Spectral Shape Matching Method (SSMM) developed by Ahn and Shanmugam (2004) is evaluated using Landsat imagery acquired over the highly turbid Saemangeum Coastal Area. The result of SSMM is compared with COST model developed by Chavez (1991 and 1997). In principle, SSMM is simple and easy to implement on any satellite imagery, relying on both field and image properties. To assess the potential use of these methods, several field campaigns were conducted in the Saemangeum coastal area corresponding with Landsat-7 satellite's overpass on 29 May 2005. In-situ data collected from the coastal waters of Saemangeum using optical instruments (ASD field spectroradiometer) consists of ChI, Ap, SS, aooM, F(d). In order to perform SSMM, we use the in-situ water-leaving radiance spectra from clear oceanic waters to estimate the the path radiance from total signal recorded at the top of the atmosphere (TOA), due to the reason that the shape of clear water-leaving radiance spectra is nearly stable than turbid water-leaving radiance spectra. The retrieved water-leaving radiance after subtraction of path signal from TOA signal in this way is compared with that estimated by COST model. The result shows that SSMM enabled retrieval of water-leaving radiance spectra that are consistent with in-situ data obtained from Saemangeum coastal waters. The COST model yielded significantly high errors in these areas.

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Changes in Bypass Flow during Temporary Occlusion of Unused Branch of Superficial Temporal Artery

  • Kim, Joon-Young;Jo, Kwang-Wook;Kim, Young-Woo;Kim, Seong-Rim;Park, Ik-Seong;Baik, Min-Woo
    • Journal of Korean Neurosurgical Society
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    • v.48 no.2
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    • pp.105-108
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    • 2010
  • Objective : Some neurosurgeons intentionally ligate the branches of the superficial temporal artery (STA) that are not used in standard STA-to-middle cerebral artery (MCA) anastomosis for the purpose of improving the flow rate in the bypass graft. We investigated changes in bypass flow during temporary occlusion of such unused branches of the STA. Methods : Bypass blood flow was measured by a quantitative microvascular ultrasonic flow probe before and after temporary occlusion of branches of the STA that were not used for anastomosis. We performed measurements on twelve subjects and statistically assessed changes in flow. We also examined all the patients with digital subtraction angiography in order to observe any post-operative changes in STA diameter. Results : Initial STA flow ranged from 15 mL/min to 85 mL/min, and the flow did not change significantly during occlusion as compared with preocclusion flow. The occlusion time was extended by 30 minutes in all cases, but this did not contribute to any significant flow change. Conclusion : The amount of bypass flow in the STA seems to be influenced not by donor vessel status but by recipient vessel demand. Ligation of the unused STA branch after completion of anastomosis does not contribute to improvement in bypass flow immediately after surgery, and furthermore, carries some risk of skin necrosis. It is better to leave the unused branch of the STA intact for use in secondary operation and to prevent donor vessel occlusion.

Effective Teaching Method for Errors Patterns in Numbers and Operations of Elementary Mathematics (수와 연산영역의 오류유형에 따른 효과적인 지도 방안)

  • Jang, Su-Yeon;Ahn, Byoung-Gon
    • Journal of Elementary Mathematics Education in Korea
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    • v.14 no.2
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    • pp.355-376
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    • 2010
  • This research was about analyzing students' major error types in the field of elementary 1st grade mathematics numbers and operations, and formulating and applying effective teaching methods to find out their effects. Among the errors the students were making, it was found that in the field of numbers there was more than 50% chance of making calculation mistakes in 50 rounds of rational counting. Also, in the field of operations, it was discovered that most of students' mistakes had to do with subtraction. The results from the classification of the 4 types of error showed that most errors were made from having inaccurate concept of knowledge and definition. Thus, it can be concluded that when elementary 1st grade teachers teach students mathematics, it is most important that they put best effort into firmly establishing the students fundamental concept, definition, facts, and functions. For that matter, students were interviewed one by one, and by implementing learning method using some concrete materials as tools, students were able to fix their own errors. More importantly, students were able to gain interest and become more willing to participate by joining in this program, which led to more effective guidance.

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Investigation on evaluation of functional dyspepsia by using Digital Infrared Thermal Images (기능성 소화불량증에 대한 적외선 체열검사(DITI)의 임상 지표적 의의 연구)

  • Jeong, Seung-Hwan;Im, In-Hwan;Um, Eun-Jin;Lee, Beom-Jun;Na, Byong-Jo
    • Journal of Oriental Medical Thermology
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    • v.6 no.1
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    • pp.56-62
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    • 2008
  • Objective: To investigate the significance of temperature differences on two different acupuncture points between functional dyspepsia(FD) group and non-functional dyspepsia(non-FD) group respectively. Methods: We performed this research on 40 patients who came and took D.I.T.I in Kang-nam korean hospital kyung-hee university. We analyzed the averaged temperature of Zhongwon(CV12), Indang(HN1) and, also, investigated the significance of subtraction from Indang to Zhongwon temperature statistically. Results: The temperature differences from Indang to Zhongwon between functional dyspepsia group and non-functional dyspepsia group was significant, it meant that patients who have functional dyspepsia have more significant temperature difference from Indang(HN1) to Zhongwon(CV12). The direct comparisons of mean temperature between Indang and Zhongwon in the FD group and non-FD group were not significant. Conclusion: The study provide hypothesis on the temperature difference from Indang(HN1) to Zhongwon(CV12) and its association with functional dyspepsia. This study can provide a foundation for future studies on the evaluation of functional dyspepsia by using D.I.T.I.

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Polymorphic Diversity of UBX Domain D from cDNA Isolated from Pectoral Muscle of Korean Native Chicken

  • Sun, Sang-Soo;Kamyab, Abdolreza;Firman, Jeff
    • Korean Journal of Poultry Science
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    • v.38 no.3
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    • pp.191-195
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    • 2011
  • The objectives of this study are to identify specific functional genes which are related with growth and protein structure of the pectoral muscle of Korean native chicken. Pectoral muscle was isolated from three Korean native chickens (KNC, red brown, 12 months old, 2.41 ${\pm}$ 0.24 kg) and three Cornish chickens (16 month old, 2.76 ${\pm}$ 3.0 kg). The subtraction cDNA library was prepared in PCR4 Blunt-TOPO vector. The DNA sequence homology was compared with other breeds and species in GenBank. A clone NDS-81 was found to be unique for the DNA sequence homology with UBX family. Their partial sequence has high homology (98%) with chicken UBX domain D. Chicken UBX domain has chicken (93%), cattle (68%), dog (67%), mouse (64%) and, human (63%) nucleotide sequence homology. Several regions were mutated from T in chicken to C or G in the NDS-81 clone. The first site is LAD in chicken, but it was expressed as (L)RM in clone NDS-81. In this site, amino acids were changed from Ala to Arg, and from Asp to Met. The second site was changed from ER (Arg) in chicken to ED (Asp) in clone NDS-81. They are both containing functional side chains and play an important role in binding other proteins. Therefore, the clone NDS-81 could be a different candidate gene for the UBX family gene and could related with pectoral muscle structure of Korean native chicken.