• 제목/요약/키워드: AM

검색결과 4,485건 처리시간 0.033초

AM50-0.3 wt%CaO 합금의 미세조직과 상·고온 기계적 특성 (Microstructure and Mechanical Properties at Room and Elevated Temperatures in AM50-0.3 wt%CaO Alloy)

  • 조은호;전중환;김영직
    • 한국재료학회지
    • /
    • 제22권10호
    • /
    • pp.499-503
    • /
    • 2012
  • The present study is intended to comparatively investigate the changes in microstructure and tensile properties at room and elevated temperatures in commercial AM50(Mg-5%Al-0.3%Mn) and 0.3 wt%CaO added ECO-AM50 alloys produced by permanent mould casting. The typical microstructure of AM50 alloy was distinctively characterized using two intermetallic compounds, ${\beta}(Mg_{17}Al_{12})$ and $Al_8Mn_5$, along with ${\alpha}$-(Mg) matrix in an as-cast state. The addition of a small amount of CaO played a role in reducing dendrite cell size and quantity of the ${\beta}$ phase in the AM50 alloy. It is interesting to note that the added CaO introduced a small amount of $Al_2Ca$ adjacent to the ${\beta}$ compounds, and that inhomogeneous enrichment of elemental Ca was observed within the ${\beta}$ phase. The ECO-AM50 alloy showed higher hardness and better YS and UTS at room temperature than did the AM50 alloy, which characteristics can be mainly ascribed to the finer-grained microstructure that originated from the CaO addition. At $175^{\circ}C$, higher levels of YS and UTS and higher elongation were obtained for the ECO-AM50 alloy, demonstrating that even 0.3 wt%CaO addition can be beneficial in promoting the heat resistance of the AM50 alloy. The combinational contributions of enhanced thermal stability of the Ca-containing ${\beta}$ phase and the introduction of a stable $Al_2Ca$ phase with high melting point are thought to be responsible for the improvement of the high temperature tensile properties in the ECO-AM50 alloy.

고려수지요법이 여대생의 생리통 및 월경곤란증에 미치는 효과 (Effects of Koryo Hand Therapy on Menstrual Cramps and Dysmenorrhea in College Women Students)

  • 김정남;장영심
    • 지역사회간호학회지
    • /
    • 제14권3호
    • /
    • pp.432-444
    • /
    • 2003
  • Purpose: This study attempted to verify the effect of Koryo hand therapy on menstrual cramps and dysmenorrhea among college students. Method: This study performed the quasi-experimental design with nonequivalent control group and the pre and post-test design from August 28 to November 4, 2002. The subjects of this experimental study consisted of 64 college students in the nursing college of K University in D city and K college students in K city, who had more than 5.0 GRS score of menstrual cramps. Among them, 16 people belonged to the experimental group A by using Ceramic Seo Am moxa therapy, 16 to the experimental group B by using Seo Am pellet therapy, 16 to the experimental group C by using combination of Ceramic Seo Am moxa therapy and Seo Am pellet therapy and 16 to the control group. Three different kinds of methods were used three times per week for $5{\sim}6$ weeks(a total of $15{\sim}18$ times) interventions were completed. For the experimental group, A Ceramic Seo Am moxa therapy was given for 40 minutes per each treatment; for the experimental group, B Seo Am pellet therapy was given for 4 hours: for the experimental group, C combination of Ceramic Seo Am moxa therapy and Seo Am pellet therapy was given. To measure menstrual cramps, the graphic rating scale (GRS) was used and to measure dysmenorrheal, a dysmenorrhea scale (15 contents) was used, which was modified from Han &Hur's scale (13 contents). Cronbach's was 0.78 in the pre-test, 0.83 in the first post-test, 0.89 in the following post-test. Data were analyzed by one-way ANOVA, 2 test, repeated measures ANOVA, time contrast test and Sheffe test with the SPSS/Win 11.0 program. Results: ? The first hypothesis, 'Among the experimental group A by using Ceramic Seo Am moxa therapy, the experimental group B by using Seo Am pellet therapy and the experimental group C by using combination of Ceramic Seo Am moxa therapy and Seo Am pellet therapy will have different graphic rating scores of menstrual cramps', was supported (F=6.77, p=0.000, Interaction: p=0.000). ? The second hypothesis, 'Among the experimental group A by using Ceramic Seo Am moxa therapy, the experimental group B by using Seo Am pellet therapy, the experimental group C by using combination of Ceramic Seo Am moxa therapy and Seo Am pellet therapy and the control group will have a significantly different level of dysmenorrhea', was supported (F=6.88, p=0.000, Interaction: p=0.000). From the above results, it can be an effective nursing intervention to give Koryo hand therapy to college students who have menstrual cramps and dysmenorrhea. Conclusion: These findings indicate that Koryo hand therapy could be applied to improve the quality of life and to prevent drug misuse among college students who are physically, mentally and psychologically suffering from menstrual cramps and dysmenorrhea. Furthermore, Koryo hand therapy could be developed as an effective Korean alternative and complementary care in the future. and it could also provide a guideline to apply Koryo hand therapy to other pain and difficulties.

  • PDF

Studies on Tolerance Level Against Antheraea mylitta Cytoplasmic Polyhedrosis Virus (AmCPV) in Different Eco-races of Tropical Tasar Silkworm, Antheraea Mylitta Drury

  • Singh, G.P.;Zeya, S.B.;Srivastava, A.K.;Ojha, N.G.;Suryanarayana, N.
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제17권1호
    • /
    • pp.153-155
    • /
    • 2008
  • Pathogenic infection in tasar silkworm, Antheraea mylitta Drury is common and there is a breed specific response regarding tolerance. Hence, the tolerance level of three eco-races of tasar silkworm viz. Daba, Sarihan and Raily to Antheraea mylitta cytoplasmic polyhedrosis virus (AmCPV) infection was tested. The survival of Daba, Sarihan and Raily eco-races was significantly different (p<0.05) when challenged with the same concentration ($1{\times}10^5$ polyhedra/ml) of AmCPV. Daba eco-race was more tolerant to the AmCPV infection having higher survival (65.7%) and $LC_{50}$ values (1000893.17 polyhedra/ml) of AmCPV followed by Sarihan eco-race (50.7% survival and $LC_{50}$ value of AmCPV 187203.6168 polyhedra/ml) and Raily eco-race (24.3% survival and $LC_{50}$ value of AmCPV 5176.37 polyhedra/ml). The tolerance level of Daba and Sarihan eco-races against AmCPV was more than two times than Raily eco-race.

한열허실변증(寒熱虛實辨證)을 이용한 비정격(脾正格) 적응증 고찰 (A Literature Study on the Application of Spleen Tonifying Sa-Am Acupuncture in the Diagnosis of Cold-Heat & Deficiency-Excess)

  • 최준수;임윤경
    • Journal of Acupuncture Research
    • /
    • 제23권5호
    • /
    • pp.31-37
    • /
    • 2006
  • Objectives & Methods : We investigated the cases for which spleen tonifying Sa-Am acupuncture was applied in ${\ulcorner}$Sa-Am-chim-gu-jeong-jeon(舍巖鍼灸正傳)${\lrcorner}$ and classified them according to the concepts of cold-heat & deficiency-excess for a better understanding of the application of spleen tonifying Sa-Am acupuncture. Results : 1. Tonification of Spleen Sa-Am acupuncture can be used to treat heat syndromes such as deficient fire caused by collapse of the spleen qi, stagnation of evil qi or spleen yin deficiency, by way of tonifying spleen qi, activating the flow of qi and blood or harmonizing spleen yin and yang. 2. Tonification of Spleen Sa-Am acupuncture can be used to treat cold syndromes such as weakness of spleen yang by way of promoting fire to generate earth, strengthening spleen yang and raising the clear yang. 3. Tonification of Spleen Sa-Am acupuncture can be used to treat deficiency syndromes such as malnutrition or poor appetite caused by spleen deficiency by way of tonifying spleen qi. 4. Tonification of Spleen Sa-Am acupuncture can be used to treat excess syndromes such as stagnation of qi and blood, abdominal mass or toxication by way of tonifying spleen qi and promoting the flow of qi and blood.

  • PDF

자연스런 인간-로봇 상호작용을 위한 음성 신호의 AM-FM 성분 분해 및 순간 주파수와 순간 진폭의 추정에 관한 연구 (AM-FM Decomposition and Estimation of Instantaneous Frequency and Instantaneous Amplitude of Speech Signals for Natural Human-robot Interaction)

  • 이희영
    • 음성과학
    • /
    • 제12권4호
    • /
    • pp.53-70
    • /
    • 2005
  • A Vowel of speech signals are multicomponent signals composed of AM-FM components whose instantaneous frequency and instantaneous amplitude are time-varying. The changes of emotion states cause the variation of the instantaneous frequencies and the instantaneous amplitudes of AM-FM components. Therefore, it is important to estimate exactly the instantaneous frequencies and the instantaneous amplitudes of AM-FM components for the extraction of key information representing emotion states and changes in speech signals. In tills paper, firstly a method decomposing speech signals into AM - FM components is addressed. Secondly, the fundamental frequency of vowel sound is estimated by the simple method based on the spectrogram. The estimate of the fundamental frequency is used for decomposing speech signals into AM-FM components. Thirdly, an estimation method is suggested for separation of the instantaneous frequencies and the instantaneous amplitudes of the decomposed AM - FM components, based on Hilbert transform and the demodulation property of the extended Fourier transform. The estimates of the instantaneous frequencies and the instantaneous amplitudes can be used for modification of the spectral distribution and smooth connection of two words in the speech synthesis systems based on a corpus.

  • PDF

돈암지구 가구(街區)의 형성과 도시한옥의 적응 (Formation of Don-am district and Adaptation of Hanok Area in Seoul)

  • 이경욱;김영수;송인호
    • 건축역사연구
    • /
    • 제30권5호
    • /
    • pp.29-42
    • /
    • 2021
  • The Don-am district is a residential area that was supplied in 1936 as a land readjustment project(Tojiguhoekjeongri). The Don-am district was newly supplied with residential areas and urban hanoks were built in large numbers. The Don-am district was influenced by urban planning and legislation at that time. These affected in the layout and plan of urban hanok. Residential block in the Don-am district were developed sequentially from the late 1930s to the 1960s. Residential block were divided by modern construction company and sold by individual lots. The blocks supplied to the Don-am district made uniformly the corner out-off(Ga gak) for creating a vehicle-centered road. So urban hanoks located in the corner plot was transformed in response to the road. Residential blocks in Don-am district was divided into three to four rows. Therefore, alleys were created inside the block. Newly made alleys consist of a privately owned road(Sa-do), a public road(Gong-Do), and open space in the site. And the alleys were used as an entry space for sharing with neighboring. Urban hanoks of Don-am district have had changed and adapted to the formation of these alleys.

황기의 볶음 조건에 따른 성분 및 자외선 광보호 활성 변화 (Changes in the constituents and UV-photoprotective activity of Astragalus membranaceus caused by roasting)

  • 박정용;이지연;김형돈;장귀영;서경혜
    • Journal of Nutrition and Health
    • /
    • 제52권5호
    • /
    • pp.413-421
    • /
    • 2019
  • 본 연구는 황기의 최적의 볶음 공정을 하였을 때 항산화 활성의 변화를 확인하기 위해 DPPH, ABTS radical scavenging assay, 총 폴리페놀 함량 및 calycosin, formononetin과 이의 배당체인 calycosin-7-O-${\beta}$-D-glucoside, Formononetin7-O-${\beta}$-D-glucoside의 분석을 실시하였다. 또한 UVB 처리로 산화적 스트레스를 유발한 HDF 세포에 추출물을 처리하여 DNA의 손상을 억제하는지 확인하였다. DPPH, ABTS radical scavenging assay 는 2R-AM 추출물에서 항산화 활성이 가장 좋았으며, 총 폴리페놀 함량은 1R-AM 추출물이 NR-AM과 비교하였을 때 월등히 증가하였지만, 2R-AM과 3R-AM과는 크게 차이가 없었다. 볶음 공정을 통한 황기는 calycosin와 formononetin의 함량이 2R-AM 추출물에서 가장 높게 측정되었다. HDF 세포에서 추출물들은 $200{\mu}g/mL$까지 독성을 나타내지 않았으며, 추출물 모두 자외선에 의해 손상된 HDF 세포에서 DNA 보호효능을 유의성 있게 증가시켰다. 특히 2R-AM 추출물의 활성은 정상세포와 유사한 수준으로 보호효과를 나타내었다. 결과를 종합해봤을 때, 볶음공정을 통한 황기 추출물은 지표 성분의 변화로 인하여 자외선에 의한 피부보호효과를 증가하였을 것이라 판단되며 이는 건강기능식품이나 화장품 원료로써 가능성을 시사한다.

Cyanex 301에 의한 Am(III)과 Eu(III)의 상호분리 (Mutual Separation of Am(III) and Eu(III) by Solvent Extraction with Cyanex 301)

  • 양한범;임재관;이일희;유재형
    • 공업화학
    • /
    • 제10권1호
    • /
    • pp.143-147
    • /
    • 1999
  • S 주개원자를 함유한 산성계 추출제인 Cyanex 301를 사용하여 $NaNO_3$ 매질에서 Am과 Eu의 추출 및 상호분리 거동에 대해 고찰하였다. Cyanex 301에 대한 Eu와 Am의 추출거동은 매우 유사하여 상호 분리할 수 없었으나, Cyanex 301을 8M NaOH로 비누화 처리한 결과 $NaNO_3$ 매질에서 Eu에 대한 Am의 선택성이 크게 증가하였다. 그리고 Am과 Eu의 상호 분리계수는 Cyanex 301의 비누화율, 수용상의 pH 및 Eu 농도가 높을수록 증가하였다. 비누화 처리하여 얻은 불균일한 Cyanex 301을 균일한 추출제를 얻기 위하여 옥탄올을 첨가하는 전처리 방법을 사용한 경우와 여과 전처리 방법을 사용한 경우 Am과 Eu의 최대 분리계수는 각각 32.3과 930을 얻었다. 그리고 Cyanex 301에 추출된 Am과 Eu은 동일한 역추출 거동을 보였으며, pH 1.3인 1 M $NaNO_3$ 용액에 의해 96.1%, 그리고 0.05 M DTPA/1.5 M Lactic acid 혼합용액에 의해서 99% 이상 역추출되었다.

  • PDF

질산용액으로부터 이온성 액체를 이용한 Am(III)과 Eu(III)의 추출 거동 (Extraction Behavior of Am(III) and Eu(III) From Nitric Acid Using Room Temperature Ionic Liquid)

  • 김익수;정동용;이근영;이일희
    • 방사성폐기물학회지
    • /
    • 제16권3호
    • /
    • pp.347-357
    • /
    • 2018
  • 이온성 액체를 이용하여 질산 용액으로부터 Am(III)과 Eu(III)의 추출 거동을 조사하고 이온성 액체의 활용가능성을 살펴보았다. 이온성 액체로는 1-alkyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide ([$C_nmim$][$Tf_2N$])을 사용하였고, n-octyl(phenyl) N,N-diisobutyl carbamoylmethyl phosphine oxide (CMPO)와 tri-n-butylphosphate (TBP)를 추출제로 사용하여, Am(III)과 Eu(III)의 추출 분배계수를 질산농도, CMPO, TBP와 같은 변수들의 함수로서 측정하였다. 이온성 액체를 사용함으로써 기존의 n-doodecane (n-DD)과 비교하여 추출 효율이 현저히 증가하였다. 질산 용액의 농도가 높을수록 Am(III)과 Eu(III)의 추출률은 감소하였으며, Eu(III)의 추출률은 Am(III)보다 전반적으로 작았다. 이온성 액체를 이용한 Am(III)과 Eu(III)의 추출 메카니즘은 n-DD와 같은 분자성 유기용매를 사용하는 경우와는 달리 양이온 교환 메카니즘에 의해 일어나는 것으로 판명되었다. 사용한 모든 이온성 액체에 대하여 Am(III)과 Eu(III)의 추출 분배계수는 CMPO의 농도가 높을수록 증가하고, CMPO 농도에 대한 추출 데이터의 직선 기울기 값은 약 3.0으로 이온성 액체를 이용한 Am(III)과 Eu(III)의 추출반응에서 3분자의 CMPO가 복합착물을 형성하는 것으로 나타났다.

Arbuscular Mycorrhizae가 탱자 유묘의 생육과 무기양분 함량에 미치는 영향 (Effects of Arbuscular Mycorrhizae on Growth and Mineral Nutrient Contents in Trifoliate Orange Seedling)

  • 오현우;김상엽;한해룡;문두길;정종배
    • 한국환경농학회지
    • /
    • 제17권2호
    • /
    • pp.182-188
    • /
    • 1998
  • 화삼회토양에서 감귤대목으로 사용되는 탱자 유모의 생육에 미치는 arbuscular mycorrhizae(AM)의 영향을 조사하기 위하여, N, P, K 시비수준을 달리한 화산회토에서 감귤뿌리를 접종 재료로 하여 AM균을 접종시킨 탱자 유묘를 재배하였다. 유모의 생육과 식물체내 무기 함량을 분석하고 감염된 화분토양에서 채취한 포자의 종류를 동정하였다. 토양 5L당 21-17-17 복비 40g과 용성인비 50g을 준 다비인산구에서만 감염된 화분의 비율이 70%였고 나머지 인산을 첨가하지 않거나 시비량이 적은 처리들에서는 감염 비율이 20% 이하였다. AM 형성율의 증가에 따라 지상부의 생채중과 건물중은 유의하게 증가 되었으며, 초장과 지하부 생채중 및 건물도 5% 수준에서 유의성은 인정되지 않았지만 증가하는 경향이었다. 따라서 식물체 내의 P와 Cu, Mg의 함량은 AM 형성율의 증가에 따라 비례적으로 유의하게 증가하였으며, N과 Zn의 함량도 증가하지만 Ca 함량은 감소하는 경향이었다. 접종 재료를 채취한 토양에서 발견되는 Glomus desertcola, G. rubiforme, G. vesiculiferm 과 Acaulospora sp. 등 4종의 AM균 포자 모두가 접종된 화분토양에서도 확인되어 이들 균이 모두 탱자 뿌리에서 AM을 형성하는 것으로 판단되었다. 토양중의 인산 수준이 감귤 뿌리의 AM균 감염을 결정하는 요인으로 작용하는 것 같으며 감귤원에서 AM을 효과적으로 이용하기 위해서는 우선 AM의 형성율을 높일 수 있는 적정 토양 인산 수준에 대한 연구가 이루어져야 할 것이다.

  • PDF