• 제목/요약/키워드: History of Pi

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2015 초등 수학 교과서 및 지도서의 수학사 기술내용 분석 (An Analysis of Descriptions about the History of Mathematics in the 2015 Mathematics Textbooks and Teacher Guides for Elementary School Level)

  • 박민구
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제36권1호
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    • pp.171-199
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    • 2022
  • 본 연구에서는 2015 초등 수학 교과서 및 지도서에서 보완이 필요한 수학사 기술내용을 파악하고 이에 대한 보완방안을 제안하고자 한다. 이를 위해 2015 초등 수학 교과서 및 지도서 24종에 대한 문헌연구를 진행하였다. 연구의 결과는 다음과 같다. 2015 초등 수학 교과서 및 지도서에서 보완이 필요한 주제는 총 10가지 주제로 '고대 이집트인의 산술', '고대 이집트 수학 교과서 A'h-mosè 파피루스', '메소포타미아 고아카디안 사각띠', '메소포타미아 고바빌로니아인과 각도', '고대 이집트인과 고바빌로니아인의 원주율', '고대 이집트인과 고바빌로니아인의 $\sqrt{2}$', '이슬람인과 소수', '황금비의 뿌리에 대한 두 가지 주장', 'Archimedes와 실진법', '평면 디자인'이었으며, 이에 대한 구체적인 보완방안을 제안하였다. 이를 통해 기축시대 역사관점을 극복하고 고대 이집트, 고바빌로니아, 고대 그리스와 헬레니즘, 중앙아시아(이슬람 1000년), 유럽으로의 수학문화 전이를 인정하고 수용하게 되기를 기대한다.

급성기 허혈성 뇌경색 환자들의 변증 분형과 위험 요인들간의 관련성 연구 (The Relationship between Pattern Identification and Stroke Risk Factors of Acute Ischemic stroke Patients)

  • 이지현;두경희;여서원;심소라;박주영;조승연;정우상;문상관;박정미;고창남;조기호;김영석;배형섭;박성욱
    • 대한중풍순환신경학회지
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    • 제13권1호
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    • pp.43-51
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    • 2012
  • Object : The purpose of this study was to evaluate the relationship between pattern identification (PI) and stroke risk factors, such as hypertension, diabetes mellitus, dyslipidemia, stroke history, obesity, abdominal obesity and metabolic syndrome. Methods : 46 patients with acute ischemic stroke were recruited from May 2012 to November, 2012. We analyzed the data of 32 patients, and pattern identification was identified by resident and specialist of Korean medicine. We analized patient's PI and risk factor by Fisher's exact test. Results : We found that Dampness-phlegm group was more related with patient's metabolic syndrome than non Dampness-Phlegm group. And Yin deficiency group had less relationship with patient's metabolic syndrome, obesity, abdominal obesity and dyslipidemia than non Yin deficiency group. Conclusions : According to the analysis, these results provide evidence for relationship between the Dampness-phlegm group, Yin deficiency and metabolic syndrome.

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세그먼트된 폴리우레탄 블렌드의 열이력에 따른 열적 성질과 분자량 변화 (Thermal Properties and Molecular Weight Variations due to Thermal History in Segmented Polyurethane Copolymer Blends)

  • 차윤종;박대운;김학림;이한섭;마석일;최순자
    • 공업화학
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    • 제10권1호
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    • pp.35-40
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    • 1999
  • Hard segment 함량이 35%와 53%로 서로 다른 두 개의 열가소성 폴리우레탄 시료 (각각 TPU-35와 TPU-35)와 이들을 70/30, 50/50, 30/70 wt%로 용융 블렌딩한 조성들이 annealing 온도와 시간에 따라 변화할 수 있는 유리전이온도와 용융피이크, 분자량 및 분자량 분포도의 변화를 관찰하였다. TPU의 $T_g$는 hard segment 함량이 많을수록 높은 값을 보였으며 annealing 온도와 시간에 따라 hard microdomain 구조의 미약한 관계에 의한 용융피이크의 크기와 온도 등이 변하였다. 이는 annealing에 의한 열이 long-range 혹은 short-range segmental motion의 거동, 비결정 microphase 구조의 order-disorder 전이, domain의 크기 및 결정구조의 질서도 등 여러 가지 복합적인 영향을 끼친 결과로 사료된다. 미세 결정의 용융 결과로 나타나는 $T_3$단일 피이크만이 존재하는 annealing 온도는 TPU-35, TPU-44와 TPU-53에 대해 각각 130, 170 및 $180^{\circ}C$이었다. Annealing 온도와 시간에 따른 분자량 및 분자량 분포도 변화 측정에서 TPU-35는 $135^{\circ}C$에서, TPU-44(TPU-35/TPU-53=50/50 블랜드)는 $170^{\circ}C$, 그리고 TPU-53은 $180^{\circ}C$에서 수평균 및 중량평균 분자량의 증가와 더불어 polydispersity(PI)는 감소를 보였다. 이 변화는 같은 조건의 annealing 온도에 따른 용융피이크 변화에서 $T_3$단일 피이크만 남게 되는 annealing온도와 일관성을 보이고 있는데, 이는 이들 시료가 특정한 annealing 온도에서 chain dissociation과 recombination이 동시에 일어나므로써 빚어진 결과로 추측된다.

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근대(近代) 도시화(都市化)에 따른 전라도(全羅道) 전통(傳統) 소도읍(小都邑)의 공간구조변화과정(空間構造變化過程) 연구(硏究) (A study on the Transformation Process of Traditional Small City Structure in Jeollabuk-Do)

  • 이경찬
    • 건축역사연구
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    • 제11권3호
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    • pp.21-34
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    • 2002
  • This study is to analyse the transformation process of spatial structure of traditional small city structure in Jeollabuk-Do in the process of modern urbanization between 19th century and the year 2000. The small cities, IM-PI, YONG-AN, YEO-SAN, OK-GOO, GO-SAN, MU-JANG, GUM-MA, GO-BU, which have been local administrative center in CHO-SUN dynasty, have role of local administrative center of subdivision of country-myon, except OK-GOO. The method of this study is to investigate the transformation process of spatial structural elements of with the actual field surveys, the analysis of Gunhyun map made in 1872, land registration maps in 1910s and 2000, and various topological maps. The elements of analysis are the topological site and geographical situation conditions, the urbanized areas, the street systems, the function of streets, the focal points of urban land use, the land use systems, and the location of major facilities such as administration facilities, markets, bus terminals. The analytical point of view and the results are as follows. There is strong relationship between the transformation of internal matrix route system and the growth pattern of urbanized areas, Especially on the contrary to the matrix route with East-West direction which has the role of checking the growth of urbanized area, the South-North direction route acts as the leading line of the growth. The focal points structure of urban land use shows transformation process from the point of central space of administrative district in front of Nae-A, to the access point to administrative district or to the access point to housing and neighborhood commercial area. From the point of functional area structure and major facilities location, line-type commercial area is developed along the line of central axis route and access route to administrative district. Especially direction of the growth of commercial area is strongly connected with the interrelationship between the study area and its neighboring cities. Pattern of commercial district development is varied with the direction of matrix route. That is, commercial district, which shows one side development pattern along the East-West direction route, is developed on both sides of street along the South-North direction route.

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Effect of Population Reduction on mtDNA Diversity and Demographic History of Korean Cattle Populations

  • Dadi, Hailu;Lee, Seung-Hwan;Jung, Kyoung-Sup;Choi, Jae-Won;Ko, Moon-Suck;Han, Young-Joon;Kim, Jong-Joo;Kim, Kwan-Suk
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권9호
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    • pp.1223-1228
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    • 2012
  • The population sizes of three Korean indigenous cattle populations have been drastically reduced over the past decades. In this study, we examined the extent to which reduction in populations influenced genetic diversity, population structure and demographic history using complete mitochondrial DNA (mtDNA) control region sequences. The complete mtDNA control region was sequenced in 56 individuals from Korean Black (KB), Jeju Black (JEB) and Korean Brindle (BRI) cattle populations. We included 27 mtDNA sequences of Korean Brown (BRO) from the GenBank database. Haplotype diversity estimate for the total population was high (0.870) while nucleotide diversity was low (0.004). The KB showed considerably low nucleotide (${\pi}$ = 0.001) and haplotype (h = 0.368) diversities. Analysis of molecular variance revealed a low level of genetic differentiation but this was highly significant (p<0.001) among the cattle populations. Of the total genetic diversity, 7.6% was attributable to among cattle populations diversity and the rest (92.4%) to differences within populations. The mismatch distribution analysis and neutrality tests revealed that KB population was in genetic equilibrium or decline. Indeed, unless an appropriate breeding management practice is developed, inbreeding and genetic drift will further impoverish genetic diversity of these cattle populations. Rational breed development and conservation strategy is needed to safeguard these cattle population.

보양환오탕가감방으로 호전된 경추 손상 유래 편측성 다한증 1례 (Improvement of unilateral hyperhidrosis in spinal cord injury following treatment with revised Boyanghwano-tang: a case report)

  • 오지석;양수영;이진우;오영선;이용구;박양춘
    • 혜화의학회지
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    • 제20권1호
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    • pp.85-89
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    • 2011
  • Hyperhidrosis is common complication of spinal cord injury, but localized unilateral hyperhidrosis is relatively rare disorder without autonomic disreflexia. A 52-year-old man with a 10-month history of cervical injury induced tetraplegia complained of excessive intermittent left-sided sweating. The sweating occurred by urinary retention or without any autonomic dysreflexia. The patient sweated excessively on the left face and upper body. In the point of Differentiation of Syndrom (辨證), the patient was diagnosed as Gi-Heo-Hyeol-Eo (Pi-Wei-Qi-Xu 氣虛血瘀) and was administered revised Boyanghwano-tang (reserved Bu-Yang-Huan-Wu-tang), and he was almost complaint free during 4 month about none dysreflexial hyperhidrosis.

Status of KASI's Contribution to SPHEREx

  • Jeong, Woong-Seob;Yang, Yujin;Park, Sung-Joon;Pyo, Jeonghyun;Jo, Youngsoo;Kim, Il-Joong;Bang, Seungcheol;Lee, Bomee
    • 천문학회보
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    • 제46권2호
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    • pp.53.1-53.1
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    • 2021
  • The KASI team are participating in the NASA MIDEX mission (PI Institute: Caltech), the all-sky infrared spectro-photometric surveyor SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer). The SPHEREx will provide us the first all-sky infrared spectro-photometric data set to probe the origin of our Universe, to explore the origin and evolution of galaxies, and to explore whether planets around other stars could harbor life. After the project PDR (Preliminary Design Review) was successfully passed on the last September, the fabrication of flight hardware is in progress. As an international partner, KASI deeply involved in all fields of projects, i.e., the development of calibration facility, the construction of data reduction modules and the science studies for the SPHEREx. After finishing the fabrication and test of calibration facility for the SPHEREx in this year, it will be delivered to Caltech. Here, we report the status of the SPHEREx project and the progress in the Korean participation.

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Recurrent Pericardial Effusion with Feline Infectious Peritonitis in a Cat

  • Baek, Su-Yeon;Jo, Jae-Geum;Song, Kun-Ho;Seo, Kyoung-Won
    • 한국임상수의학회지
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    • 제34권6호
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    • pp.437-440
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    • 2017
  • A five-month-old, male Domestic Korean shorthair was referred to our hospital with a history of lethargy, anorexia, and globoid cardiac silhouette on thoracic radiography. Physical examination showed dehydration and anemia was revealed on blood analysis. On thoracic radiography and echocardiography, the patient showed pericardial effusion and ultrasound-guided pericardiocentesis was performed. A Rivalta test of the pericardial effusion showed a positive result. As the patient had recurrent pericardial effusion, pericardiectomy was performed. He was tentatively diagnosed with wet form feline infectious peritonitis (FIP) and treated with Polyprenyl immunostimulant (PI). Neurological signs were eventually seen and he was euthanized. Histopathologic changes with markedly expanded neutrophils, lymphocytes, plasma cells, and macrophages with fibrous connective tissue and collagenous fibers were detected. Immunohistochemistry for FIP antigen was performed and results showed FIPV-positive multifocal aggregates of cells. Pericardial effusion is an atypical condition in cats with FIP, but can be presented. This case report describes FIP with pericardial effusion in a cat, in which definitive diagnosis of FIP was done using biopsy via pericardiectomy.

생태 관광 정보 제공을 위한 플랫폼 설계 (The Design of Platform for Ecotourism Information Supply)

  • 권성현;김영근;손철수;김원중
    • 한국전자통신학회논문지
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    • 제13권2호
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    • pp.419-426
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    • 2018
  • 생태 관광이란 우수한 자연자원과 주변의 역사, 문화 자원 체험을 통해 느끼고 관찰하는 관광을 말하며, 현재 국민들의 여가생활 패턴이 변경됨에 따라 자연을 찾는 힐링(healing) 여행이 활성화 되고 있다. 본 논문에서는 계절에 따라 변화하고 특정한 시기에만 관람이 가능한 생태 관광 프로그램의 문제점을 해결하고 지속 가능한 생태 관광이 이루어 질 수 있는 관광 콘텐츠 시스템을 제안한다. 제안하는 관광 콘텐츠 시스템은 이미지 촬영 단말기에서 매일 촬영한 생태 관광 이미지 파일을 수거하여 동영상으로 변환 후 서버에 업로드 하면 관광객이 생태 관광 객체에 도착했을 때, 스마트폰을 이용하여 알려주고 식물의 성장 과정 등을 동영상으로 관람할 수 있도록 설계하였다.

Status Report of the NISS and SPHEREx Missions

  • Jeong, Woong-Seob;Park, Sung-Joon;Moon, Bongkon;Lee, Dae-Hee;Park, Won-Kee;Lee, Duk-Hang;Ko, Kyeongyeon;Pyo, Jeonghyun;Kim, Il-Joong;Park, Youngsik;Nam, Ukwon;Kim, Minjin;Ko, Jongwan;Im, Myungshin;Lee, Hyung Mok;Lee, Jeong-Eun;Shin, Goo-Hwan;Chae, Jangsoo;Matsumoto, Toshio
    • 천문학회보
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    • 제41권1호
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    • pp.58.2-58.2
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    • 2016
  • The NISS (Near-infrared Imaging Spectrometer for Star formation history) onboard NEXTSat-1 is the near-infrared instrument optimized to the first small satellite of NEXTSat series. The capability of both imaging and low spectral resolution spectroscopy with the Field of View of $2{\times}2deg.$ in the near-infrared range from 0.9 to $3.8{\mu}m$ is a unique function of the NISS. The major scientific mission is to study the cosmic star formation history in local and distant universe. The Flight Model of the NISS is being developed and tested. After an integration into NEXTSat-1, it will be tested under the space environment. The NISS will be launched in 2017 and it will be operated during 2 years. As an extension of the NISS, SPEHREx (Spectro-Photometer for the History of the Universe Epoch of Reionization, and Ices Explorer) is the NASA SMEX (SMall EXploration) mission proposed together with KASI (PI Institute: Caltech). It will perform an all-sky near-infrared spectral survey to probe the origin of our Universe; explore the origin and evolution of galaxies, and explore whether planets around other stars could harbor life. The SPHEREx is designed to have wider FoV of $3.5{\times}7deg.$ as well as wider spectral range from 0.7 to $4.8{\mu}m$. After passing the first selection process, SPHEREx is under the Phase-A study. The final selection will be made in the end of 2016. Here, we report the current status of the NISS and SPHEREx missions.

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