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Properties of No-coarse Lightweight Concrete Using Synthetic Lightweight Fine Aggregate (인공경량세골재(人工輕量細骨材)를 사용(使用)한 무조골재(無粗骨材) 경량(輕量)콘크리트의 특성(特性))

  • Min, Jeong Ki;Kim, Seong Wan;Sung, Chan Yong
    • Korean Journal of Agricultural Science
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    • v.24 no.2
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    • pp.194-206
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    • 1997
  • This paper was performed to evaluate the properties of no-coarse lightweight concrete using perlite and expanded polystyrene bead on fine aggregate. The results were shown that w/c and unit weight was affected by absorption ratio and unit weight of using aggregate itself. The compressive strength of no-coarse lightweight concrete was showed $187kgf/cm^2$ by using natural sand, $170kgf/cm^2$ by using perlite. Tensile and bending strength were showed the same tendency of compressive strength, but when expanded polystyrene bead concrete dose not have strength nearly. The pulse velocity and static modulus of elasticity of no-coarse lightweight concrete were smaller than that of normal cement concrete. And stress-strain curves were shown that was increased with increase of stress, and when the stress-strain curve using expanded polystyrene bead was repeated at short intervals increase and decrease irregularly.

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Preliminary Report of Use-Effectiveness of Ovulation Method in Korea (자연피임법으로서의 배란법의 피임효과)

  • Bae, S.C.;Chung, Y.J.;Rha, J.G.;Oh, W.S.;Kim, S.J.
    • Clinical and Experimental Reproductive Medicine
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    • v.3 no.1
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    • pp.27-32
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    • 1976
  • In recent years, explosive increase in population has been damaging mankind in terms of deprivation of natural resources and more of economical demands. Therefore, we have thought about problems as to counter-balance the increasing population, and reached a resolution of artificial methods of controlling birth. In the past, though now used in some of contraceptive methods, extravaginal ejaculation, condom were commonly used. But recently, pills, IUD and several kinds of operative procedures are quite popular. Though the recent methods are known to be effective compared with the traditional methods, a certain unwanted side effects as well as limited value of usages now must be discussed. On this aspect, we are trying to research for a ideal methods such as symptom free, more of natural way of family planning and try to zero the failure rate. And also it has been suggested that only if those scientific methods of controlling birth can be base on religious concepts of moral being, it will be enlightened. At the Happy Family Planning Clinic of St. Mary's Hospital, we apply Billing's ovulation method to out-patients who want contraception and usually advise them to use it on a self-care basis. For a retrospective study of the presurvey data analysis and use-effectiveness of the ovulation method from April 1, 1975 to Nov., 30, 1975, we have dealt with a total of 1,383 women (urban areas 465, rural areas 918). The results of preliminary survey were as follows; 1) Among 465 women in Seoul areas, the failure rate was 10.3, which signified unplanned pregnancies of 32 women. 27 of the 32 women were pregnant due to the users own failure and the remaing 5 due to the failure of the method. Therefore, the failure of the method accounted for 1.6. 2) Among 918 women in rural areas, the failure rate was 15.2 signifing unplanned pregnancies in 93 women. The cause of the failure in 81 of the 93 women was attributable to the user's own mistake and that in the remaing 12 to the default of the method. Therefore, the failure attributable to the method accounted for 2.0.

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The Effects of the Epithelial Cells of Genital Tract on the Development of Mouse Early Embryos and Human Fertilized Oocytes (생쥐 초기배아와 사람의 수정란의 발생에 미치는 생식수관 상피세포의 영향에 관한 연구)

  • Lee, H.J.;Byun, H.K.;Kim, J.W.;Hwang, J.H.;Jun, J.Y.;Kim, M.K.
    • Clinical and Experimental Reproductive Medicine
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    • v.21 no.3
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    • pp.315-323
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    • 1994
  • Mammalian oviductal epithelial cells have been known to improve in vitro fertilization and embryonic development. Recently, co-cultured human embryos with the epithelial cells in human genital tract has been reported to improve the pregnancy rate. The purpose of the study was to investigate the effects of the epithelial cells of human genital tract on the development of mouse early embryos and human fertilized oocytes. The epithelial cells of human genital tract were collected from the fallopian tubes which were obtained during hysterectomy in fertile women and from the endometrium during endometrium biopsy. Collected human ampullary cells(HACs) and endometrial cells(HECs) were cultured for 10 days to establish primary monolayer. Second passaged HACs and HECs were obtained by trypsinization were cryopreserved in PBS with 1.5 M DMSO for later use. To investigate the effect when co-cultured with HACs and HECs, we tried to apply strict quality control on mouse embryo, from two cell to blastocyst prior to human trial. The results of quality control were as follows; In Group I (Ham's F10 with 10% FCS), Group IT (co-cultured with HACs) and Group ill (co-cultured with HECs), developmental rates to blastocyst were 63.3%(253/400), 76.0%(304/ 400),74.0%(296/400), respectively. Hatching rates were 36.8%(147/400), 41.80/0(167/400), 38.0%(152/400), respectively(p<0.05). To perform the human IVF, cryopreserved HACs were thawed at 37$^{\circ}C$ waterbath, seeded on the well dish and cultured for 48 hI'S. The pronuclear stage embryos were transferred to the seeded well dish. After 24 hRS, co-cultured embryos were examined and transferred to patient's uterus. The results of human IVF when co-cultured with HACs were that fertilization and developmental rates were 61.8% (256/414), 95.3% (244/256) as compared with 57.2% (279/488) and 94.6%(264/279) in Ham's F10 supplemented with 10% FCS(control). However, 62.9% (161/256) of co-cultured human embryos showed good embryos(no or slight fragmentation) as compared with 53.8 % (150/279) in control(p < 0.05). Pregnancy rate was 40.0% (12/30) when co-cultured with HACs whereas 30.6%(11/36) in control. In conclusions, co-culture system using HACs and HECs improved the developmental and hatching rates of mouse embryo. Also, in human IVF system when co-cultured with HACs, it improved both the quality of human embryos and the pregnancy rate.

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Meaning Analysis (의미 분석)

  • Lee, Gun-Won
    • Annual Conference on Human and Language Technology
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    • 2000.10d
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    • pp.419-423
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    • 2000
  • 성공적인 의사소통의 경우에 성(性)이, 이(理)와 명(命)으로 나타난 것이 같다. 진리(aletheia)가, 언어(logos)와 운명(moira)으로 나타난 것들이 일치하는 것이 성공적인 언화행위가 된다. 측정대상(melos)과 본체(ousia)가 구분되는 것은 언어와 운명의 괴리가 있을 수가 있기 때문이다. 체계적인 언어처리의 지식기반을 측정대상에 한정한다. (1) 철학의 시작은 더 옳은 언어표현의 정의(definition)로 이전의 잘못 사용된 언어처리를 대체시키는 것으로 소크라테스는 보았다. [R. Crossman] (2) 잘못을 지적하는 등에(Tabanidae)의 역할과 옮은 지식의 상기를 돕는 산파법(maieutics)이 소크라테스의 의미분석의 방법이다. [R. Crossman] (3) 언어를 통하여 진리를 추구한다는 입장(via language)애서 한 언어표현이 그 진리의 운명으로 나타남과 어긋날 때, 운명을 택하는 것은 조화 보다 더 안정의 우위를 인정하는 논리적인 입장으로 합리성 보다 실용(pragma)의 우위를 인정하는 것이다. [W. Quine] (4) 공동체의 공통규범의 추구는 그 언어 속의 공통의 형식 또는 법칙의 추구에 기초하는 것이 자연스럽다. 여기에서 그 언어사용은 그 기저의 법칙(underlying rule)에 개입한다는 입장에 기초한다. [J. Searle] (5) 진리의 언어표현과 운명적인 사태들 사이의 괴리를 처리하기 위하여 체계적인 언어표현의 대상(The Young Tableaux)과 실제(The continuum)의 구분을 수용한다. [AMS(2000)] 언어표현의 대상은 나타난 것(현)(顯)이고 실제에는 나타나지 않은 것도 있다. 이천(伊川), 명도(明道)] (6) 이 나타난 것과 나타나지 않은 것에 간격이 없다는 것(현미무간)(顯微無間)은 그 의사소통이 성공적인 것이라는 것을 말한다. 따라서 그 언어의 표현완전성(functional completeness)은 언화행위가 성공적이라는 것이다.[J. Searle] (7) 수로 쓰인 것(상수)(象數)과 시로 쓰인 것(의리)(義理)이 하나인 것은 그 나타난 것과 나타나지 않은 것들 사이에 어떠한 들도 없음을 말한다. [(성중영)(成中英)] (8) 공통의 규범의 공통성 속에 규범적인 측면이 벌써 있다. 공통성에서 개인적이 아닌 공적인 규범으로의 전이는 규범, 가치, 규칙, 과정, 제도로의 전이라고 본다. [C. Morrison] (9) 우리의 언어사용에 신비적인 요소를 부인할 수가 없다. 넓은 의미의 발화의미(utterance meaning) 속에 신비적인 요소나 애정표시도 수용된다. 의미분석은 지금 한글을 연구하고, 그 결과에 의존하여서 우리의 실제의 생활에 사용하는 $\ulcorner$한국어사전$\lrcorner$ 등을 만드는 과정에서, 어떤 의미에서 실험되었다고 말할 수가 있는 언어과학의 연구의 결과에 의존하여서 수행되는 철학적인 작업이다. 여기에서는 하나의 철학적인 연구의 시작으로 받아들여지는 이 의미분석의 문제를 반성하여 본다.

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Acute and repeated dose 26-week oral toxicity study of 20(S)-ginsenoside Rg3 in Kunming mice and Sprague-Dawley rats

  • Li, Chunmei;Wang, Zhezhe;Li, Guisheng;Wang, Zhenhua;Yang, Jianrong;Li, Yanshen;Wang, Hongtao;Jin, Haizhu;Qiao, Junhua;Wang, Hongbo;Tian, Jingwei;Lee, Albert W.;Gao, Yonglin
    • Journal of Ginseng Research
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    • v.44 no.2
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    • pp.222-228
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    • 2020
  • Background: 20(S)-ginsenoside-Rg3 (C42H72O13), a natural triterpenoid saponin, is extracted from red ginseng. The increasing use of 20(S)-ginsenoside Rg3 has raised product safety concerns. Methods: In acute toxicity, 20(S)-ginsenoside Rg3 was singly and orally administrated to Kunming mice and Sprague-Dawley (SD) rats at the maximum doses of 1600 mg/kg and 800 mg/kg, respectively. In the 26-week toxicity study, we used repeated oral administration of 20(S)-ginsenoside Rg3 in SD rats over 26 weeks at doses of 0, 20, 60, or 180 mg/kg. Moreover, a 4-week recovery period was scheduled to observe the persistence, delayed occurrence, and reversibility of toxic effects. Results: The result of acute toxicity shows that oral administration of 20(S)-ginsenoside Rg3 to mice and rats did not induce mortality or toxicity up to 1600 and 800 mg/kg, respectively. During a 26-week administration period and a 4-week withdrawal period (recovery period), there were no significant differences in clinical signs, body weight, food consumption, urinalysis parameters, biochemical and hematological values, or histopathological findings. Conclusion: The mean oral lethal dose (LD50) of 20(S)-ginsenoside Rg3, in acute toxicity, is above 1600 mg/kg and 800 mg/kg in mice and rats, respectively. In a repeated-dose 26-week oral toxicity study, the no-observed-adverse-effect level for female and male SD rats was 180 mg/kg.

Relationship Between The Sasang Constitution and Ace Polymophism (사상체질유형과 ACE(angiotensin converting enzyme) 유전자 Type(polymorphism)과의 상관관계)

  • Choi, S.H.;Yim, Y.B.;Rhee, J.W.;Kim, H.Y.;Kang, C.H.
    • Journal of Sasang Constitutional Medicine
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    • v.10 no.2
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    • pp.283-290
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    • 1998
  • Sasang Constitutional Medicine focuses on the different constitutional manifestations of the individual's nature and emotions. The nature and emotions drive the ascending and descending of Qi in the body. And this dynamics of the Qi's ascent and descent shapes the different types of structures, functions and temperaments. Although Sasang Constitutional Medicine has many advantages, its diagnosis of the constitution still depends on the doctors' own idea and has no objective identification. So many doctors in Korea have been trying to solve this problem. Recently, there are several efforts to find out the relationship between genetic information and constitution. By the way, May, 1998 there is a astonishing report about the gene which determines the human performance, that is ACE(angiotensin converting enzyme). And it suggests that the I allele was associated with improved endurance performance. ACE has three genotype including II, ID and DD. "I" means insertion and "D" means deletion. We determined the type of the Sasang constitution with QSCCII questionaire and the one's ACE genotype with PCR of the 127 people and we discovered the relationship between the constitution and the ACE genotype. The result is as follow. Among 39 people who have the II genotype, 7(18%) belong to Taeum(Taiyin), 9(23.1%) belong to Soyang(Shaoyang) and 23(59%) belong to Soeum(Shaoyin). Among 62 people who have the ID genotype, 18(29%) belong to Taeum(Taiyin), 21(33.9%) belong to Soyang(Shaoyang) and 23(37.1%) belong to Soeum(Shaoyin). Among 26 people who have DD genotype, 11(42.3%) belong to Taeum(Taiyin), 4(15.4%) belong to Soyang(Shaoyang) and 11(42.3%) belong to Soeum(Shaoyin). This data indicates that there are implicable relationship between the Sasang constitution and ACE genotype. Especially people who have II genotype have much possibility to be a Soeum(Shaoyin) person (59%) and Soyang(Shaoyang) person have less possibility to have DD genotype (15.4%). With this conclusion, we suggest further study of relationship between the Sasang constitution and ACE genotype and we think that other polymorphism can be a candidate of the partner of Sasang constitution.

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Changes in Moisture Content and Quality of Chewing Gum during Storage (저장중 츄잉껌의 수분함량과 품질변화)

  • Chung, Duk-Ho;Lee, Yoon-Hyung;Yoo, Myung-Shik;Pyun, Yu-Ryang
    • Korean Journal of Food Science and Technology
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    • v.24 no.2
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    • pp.117-121
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    • 1992
  • The changes in sensory and mechanical texture of chewing gum during storage at various relative humidity were studied to define the quality index for the prediction of shelf-life. The initial moisture content of chewing gum was 2.57% (dry basis). The BET monolayer value at $a_{w}$ 0.19 was calculated to be 1.57% (dry basis). The sensory scores of chewing gum were closely correlated with moisture content and instrumental texture parameters with 0.1% significant level. Therefore the quality of stored chewing gum was directly related with moisture content above BET monolayer. The products became organoleptically acceptable in the range of moisture content $2.17{\sim}3.16%(dry basis)$. This range of moisture content ie equivalent to the ranges of instrumental parameter, fracture force$0.8{\sim}1.8{\times}10^{7}$, fracture modulus $1.1{\sim}2.4{\times}10^{8}$, puncture force $0.5{\sim}1.1{\times}10^{7}[dyne/cm^{2}]$ and brittleness $0.7{\sim}1.4{\times}10^{8}[dyne/cm^{3}]$, respectively.

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New transfer standard for low vacuum region

  • 우삼용;한승웅;김부식;이상균
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.44-44
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    • 1999
  • 저진공(1 kPa~ 100 kPa)은 대기압 측정, 비행고도, 기체의 온도 측정, 질량의 부력 보정, 레이저의 굴절률 측정등에 사용되는 영역으로 과학적 중요성을 갖고 있다. 또한 대기압 이상의 압력 측정과 고진공 측정의 경계적 역할도 수행하고 있어 압력 표준기의 국제 비교에 필수적으로 권장되는 역역이다. 이 영역에 주로 사용되는 압력 표준기는 수은 압력계(Mercury manometer)와 분동식 압력계(Deadweight piston gauge or Pressure)가 있다. 이들은 이동이 불편하거나 불가능하므로 표준기의 국제 비교에 사용되는 전달 표준기로는 보다 이동이 간편한 탄성 압력계인 CDG(Capacitance diaphragm Gauge)가 있다. 이 게이지는 반도체 산업의 공정 제어용으로도 많이 사용되고 있다. 그러나 게이지와 함께 사용되는 컨트롤러의 부피가 크고 무거우며 영점 이동이 커서 측정때 마다 재조정하여야 하는 단점이 있다. 본 논문에서는 이 같은 단점을 극복하기 위해 수정빔 진동형 진공 센서를 잔달 표준기로 사용하는 것에 대한 연구를 수행하였다. 수정빔 진동형 압력 센서는 수정빔으 공진주파수가 스트레인에 비례하는 것을 이용하여 제작된 센서로 주로 대기압 이상의 고압 측정에 많이 사용되고 있다. 먼저 수정빔의 압력과 주파수간의 관계를 측정하고 또한 내장된 수정 온도센서의 공진 주파수를 측정하여 온도 보상을 위한 자료로 사용하였다. 규격에 나와 있는 수정빔의 기하학적 형상으로부터 거동에 관한 이론 모델식을 구하고 압력교정 자료로부터 얻어진 데이터를 이 식과 비교 분석하여 적합한 특성식과 인자를 구하였으며 게이지의 불확도를 추정하였다.모델은 길이가 유한한 0-차원 실린더 모델로 가정하였고, 이에 대한 기하학적 성질 및 열역학적 성질은 유효계수를 고려하여 산출하였다. 진공용기 이중 벽 내부로 흐르는 질소가스의 유량과 온도의 계산은 진공용기 내벽과 외벽을 각각 독립적인 열전달 요소로 가정하여 구성한 모델을 이용하였다. 전체 해석에서 각 열전달 요소의 비열 값은 온도에 따라 변화하는 비열의 특성을 반영하였으며. 진공용기와 플라즈마 대향 부품의 방사율(emissivity)은 앞서 가정했던 각 온도 상승 곡선에 대해서 각각 0.1, 0.2, 1.3의 경우를 가정하여 계산하였다. 직선적으로 증가하는 온도 상승 곡선중 2$0^{\circ}C$/hr의 온도상승율을 갖는 경우가 다른 베이킹 시나리오 모델에 비해 효과적이라 생각되며 초대 필요 공급열량은 200kW 정도로 산출되었다. 실질적인 수치를 얻기 위해 보다 고차원 모델로의 해석이 필요하리라 생각된다. 끝으로 장기적인 관점에서 KSTAR 장치의 베이킹 계획도 살펴본다.습파라미터와 더불어, 본 연구에서 새롭게 제시된 주기분할층의 파라미터들이 모형의 학습성과를 높이기 위해 함께 고려된다. 한편, 이러한 학습과정에서 추가적으로 고려해야 할 파라미터 갯수가 증가함에 따라서, 본 모델의 학습성과가 local minimum에 빠지는 문제점이 발생될 수 있다. 즉, 웨이블릿분석과 인공신경망모형을 모두 전역적으로 최적화시켜야 하는 문제가 발생한다. 본 연구에서는 이 문제를 해결하기 위해서, 최근 local minimum의 가능성을 최소화하여 전역적인 학습성과를 높여 주는 인공지능기법으로서 유전자알고리즘기법을 본 연구이 통합모델에 반영하였다. 이에 대한 실

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Duration of Competition and the Competitive Ability of Red Rice with Rich by Replacement Diagram (적미(赤米)의 경합기간(競合期間)과 밀도(密度)가 수도생육(水稻生育) 및 수량(收量)에 미치는 영향(影響))

  • Ree, D.W.;Kim, J.C.;Kim, Y.H.;Hong, Y.K.;Son, S.Y.
    • Korean Journal of Weed Science
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    • v.7 no.1
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    • pp.45-51
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    • 1987
  • This experiment was conducted to find out the critical competitive period and competitive ability of rice against red rice. Plant height and number of tillers of rice decreased as red rice competed with rice during active tillering stage. The maximum tillering stage of rice competed with red rice became about 10days earlier than those non-competed. Significant yield reduction of rice was observed in the plots competed for 20 days after transplating or longer. Such a yield reduction can be mainly attributed to the decrease in number of panicles per hill and grain number per panicle. In a replacement diagram for rice and red rice, their competition is turned out being antagonized. The relative yield total was considered lower than 1. Grain number, culm and panicle length of rice was not affected significantly by inter-specific competition. Rice grain yield reduction was highly correlated with the number of panicles of red rice. Three hundred panicles/$m^2$ of the red rice were necessary to reduce rice grain yield by 50% of the check plot.

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The Influence of $O_2$ Partial Pressure on Soft Magnetic Properties of As-deposited Fe-Sm-O Thin Films (산소분압에 따른 Fe-Sm-O계 박막의 연자기적 성질)

  • Yoon, T.S.;Cho, W.S.;Koo, E.S.;Li, Ying;Park, J.B.;Kim, C.O.
    • Korean Journal of Materials Research
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    • v.10 no.11
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    • pp.755-759
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    • 2000
  • The influence of $O_2$partial presure on saturation magnetization, coercivity and effective permeability(0.5~100MHz) of as-deposited Fe-Sm-O thin films, which were fabricated by RF magnetron reactive sputtering method, were investigated. The nanocrystalline Fe(sub)83.4Sm(sub)3.4O(sub)13.2 thin film fabricated at $O_2$partial pressure of 5% exhibits the best magnetic softness with saturation magnetization of 18kG, coercivity of 0.82 Oe and effective permeability about 2,600 at 0.5~100MHz. $\alpha$-Fe grain size is decreased with increasing $O_2$partial pressure. In case of $O_2$partial pressure of 10%, it is observed that FeO compound is formed and soft magnetic properties are decreased. The electrical resistivity of Fe-Sm-O thin films were increased with increasing $O_2$partial pressure, the electrical resistivity of Fe(sub)83.4Sm(sub)3.4O(sub)13.2 thin film with the best soft magnetic properties was 130 $\mu$$\Omega$cm. Therefore, It is assumed that the good soft magnetic properties of Fe(sub)83.4Sm(sub)3.4O(sub)13.2 thin film results from high electrical resistivity and decreasing $\alpha$-Fe grain size due to precipitation of Sm-Oxide phase.

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