• 제목/요약/키워드: Non-determination

검색결과 1,031건 처리시간 0.035초

Comparison of linear and non-linear equation for the calibration of roxithromycin analysis using liquid chromatography/mass spectrometry

  • Lim, Jong-Hwan;Yun, Hyo-In
    • 대한수의학회지
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    • 제50권1호
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    • pp.11-17
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    • 2010
  • Linear and non-linear regressions were used to derive the calibration function for the measurement of roxithromycin plasma concentration. Their results were compared with weighted least squares regression by usual weight factors. In this paper the performance of a non-linear calibration equation with the capacity to account empirically for the curvature, y = ax$^{b}$ + c (b $\neq$ 1) is compared with the commonly used linear equation, y = ax + b, as well as the quadratic equation, y = ax$^{2}$+ bx + c. In the calibration curve (range of 0.01 to 10 ${\mu}g/mL$) of roxithromycin, both heteroscedasticity and nonlinearity were present therefore linear least squares regression methods could result in large errors in the determination of roxithromycin concentration. By the non-linear and weighted least squares regression, the accuracy of the analytical method was improved at the lower end of the calibration curve. This study suggests that the non-linear calibration equation should be considered when a curve is required to be fitted to low dose calibration data which exhibit slight curvature.

수삼의 지역별 연근별 인삼 비사포닌 성분 함량 비교 (Comparison of Non-saponin Composition and Contents in Fresh Ginseng Roots Cultivated in Different Areas and at Various Ages)

  • 양병욱;임병옥;고성권
    • 약학회지
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    • 제50권4호
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    • pp.215-219
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    • 2006
  • This study was carried out to obtain the basic information for non-saponin contents that can be used to index fresh ginseng roots (Panax ginseng C. A. Meyer) cultivated in the Republic of Korea and China. Non-saponin components in fresh gingeng roots which were cultivated in various areas and ages in Korea were determined. Acidic polysaccharide, total polysaccharide, crude polyacetylene were quantitatively analyzed by using the method of spectrophotometric determination, while the total protein was analyzed by using Lowry method. The results show that there were no statistically significant differences for the average contents of four non-saponins among 4-years-old, 5-years-old, and 6-years-old fresh ginseng roots. Additionally, this study assessed the average contents of non-saponin components in 4-years-old fresh ginseng roots (Panax ginseng C. A. Meyer) which were cultivated in Korea and China. The result showed that the average contents of crude polyacetylene and acidic polysaccharide were statistically significant. Four-years-old fresh ginseng roots cultivated in Korea had the higher average contents of crude polyacetylene and acidic polysaccharide than those cultivated in China. However the average contents of total polysaccharide and total protein had no statistically significant difference.

Performance Determination of Novel Design Eddy Current Separator for Recycling of Non-Ferrous Metal Particles

  • Fenercioglu, Ahmet;Barutcu, Hamit
    • Journal of Magnetics
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    • 제21권4호
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    • pp.635-643
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    • 2016
  • Improvements were made in the study for the design of the conventional Eddy Current Separator (ECS) used for separating small sized non-ferrous particles in the waste. These improvements include decreasing the air gap between the material and magnetic drum, making the drum position adjustable and placing the splitter closer to the drum. Thus, small particles were separated with high efficiency. The magnetic drum was removed from inside the ECS conveyor belt system as design change and was placed as a separate unit. Hence, the force generated on the test material increased by about 5.5 times while the air gap between the non-ferrous materials and drum decreased from 3 mm to 1 mm. The non-metal material in the waste is separated before the drum in the novel design. Whereas non-ferrous metal particles are separated by falling into the splitter as a result of the force generated as soon as the particles fall on the drum. Every material that passes through the drum can be recycled as a result of moving the splitter closer to the contact point of the drum. In addition, the drum can also be used for the efficient separation of large particles since its position can be adjusted according to the size of the waste material. The performance of the novel design ECS was verified via analytical approaches, finite element analysis (FEA) and experimental studies.

Synthesis and comparison of pure TiO2 and metal/non-metal doped TiO2 as a photocatalyst

  • Moon, Jiyeon;Lee, Kyusang;Kim, Seonmin
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.370.1-370.1
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    • 2016
  • Volatile organic compounds (VOCs) are considered hazardous air pollutants and these are emitted from building materials and household products. VOCs can cause global warming as well as human sickness, and even cancer. Photocatalysis provides a way of converting VOCs into harmless materials. Various researches have shown that $TiO_2$ is the most efficient photocatalysts due to its excellent activity. In this study, metal/non-metal doped $TiO_2$ particles are synthesized for the enhancement of the photocatalytic properties of pure $TiO_2$. By metal/non-metal doping, band gap energies of prepared samples were analyzed by UV/Visible spectrophotometer. The physical and chemical properties of synthesized powder were characterized by field emission scanning electron microscope, by BET for measuring their specific surface area, and by XRD for phase identification and particle size determination. Degradation ability for p-xylene was evaluated through monitoring the concentration in a closed chamber. Relation between their properties and decomposition abilities for VOC were evaluated based on the experimental results.

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Coronary Artery Numerical Flow Analysis for Determination of Bypass Graft Geometric Parameters

  • Kim, Hyung-Min;Kim, Woong
    • Journal of Mechanical Science and Technology
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    • 제19권3호
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    • pp.905-912
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    • 2005
  • A computational investigation of blood flow in a coronary artery grafted by artificial bypass was performed to determine such geometric parameters as the curvature of radius, approach length, and angle of end-to-side anastomosis. Transient flow features in the host artery were computed using FVM and SIMPLE algorithms. We compared flow distributions and wall shear stresses in two simple models, planar and non-planar, and confirmed that the non-planar bypass model was more conducive to suppressing intimal hyperplasia. Our non-planar model with $60^{\circ}$ of anastomosis and a 1.0 diameter approach length and radius of curvature predicts a relatively small, spatially-extended high-OSI (>0.01) zone, as well as an increased average wall shear stress on this zone.

수치해석법에 의한 비대칭 변단면 기둥의 탄성 임계하중 (Elastic Critical Load of Non-symmetrically Tapered Columns by Numerical Method)

  • 신세욱;김선혜;이수곤
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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    • pp.11-18
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    • 1999
  • For the proper design of a slender compression member, the exact determination of the elastic critical load is crucial, In the cases of non-prismatic compression members, the determinations of the elastic critical load cannot be usually expressed in closed forms. h this paper, the non-symmetrically tapered compression members with arbitrary boundary conditions me analysed by using the finite element method to determine the elastic critical load. The main parameters considered in the numerical analysis are the In Parameter, $\alpha$ and the sectional property parameter, m. To generaliza the unmerical analysis, of the computed results for each sectional parameter, m are presented in algebraic equations, which agrees fairy well with those by F.E.M in most cases.

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단순지지 변단면 압축재의 임계하중 (Elastic Critical Laod of Tapered Columns)

  • 홍종국;김순철;이수곤
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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    • pp.252-259
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    • 1999
  • One of the most important factors for a proper design of a slender compression member may be the exact determination of the elastic critical load of that member. In the cases of non-prismatic compression member, however, there are times when the exact critical load becomes impossible to determinate if one relies on the neutral equilibrium method or energy principle. Here in this paper, the approximate critical loads of symmetrically or non-symmetrically tapered members are computed by finite element method. The two parameters considered in this numerical analysis are the taper parameter, $\alpha$ and the sectional property parameters, m. The computed results for each sectional property parameter, m are presented in an algebraic equation which agrees with those by F.E.M The algebraic equation can be easily used by structural engineers, who are engaged in structural analysis and design of non-prismatic compression member.

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도의 철학과 도의 언어학 -고대 중국의 철학과 언어- (The Philosophy and Linguistics of Dao : the Ancient Chinese Philosophy and Language)

  • 정재현
    • 인문언어
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    • 제5권
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    • pp.109-126
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    • 2003
  • The aim of this paper is to elucidate ancient Chinese philosophy and linguistics through the concept of the Dao. Ancient Chinese thought had developed together with ancient Chinese theories of language and the linguistic features of Classical Chinese. The concept of the Dao served as an intermediary among them. The Dao which ancient Chinese philosophers sought for has several characteristics: ethical normativity, wholeness, dynamicity, non-reducibility. Linguistic studies also revealed them. The following linguistic features of Classical Chinese are the cause and/or the effect of such Dao-based philosophy and linguistics: No explicit subject-predicate sentential structure, no parts of speech, heavy reliance on the word order and context for meaning determination, no explicit distinction between compound words and a sentence, the pictographic or the ideographic features of Chinese graphs, and non-existence of a copula.

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정현상 비대칭으로 Taper진 부재의 임계하중과 고유진동수와의 관계 (The Relationship between Critical Load and Frequency of Sinusolidally Non-symmetrically Tapered Member)

  • 이혁;홍종국;이수곤
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 가을 학술발표회논문집
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    • pp.59-66
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    • 2000
  • It is generally known that the lateral frequency( ω) of the vibration of a prismatic beam-column decreases according to the rele (equation omitted) (ω/sub 0/=natural frequency). In the cases of tapered members, the determination of P/ sub/ cr/(elastic critical load) and ω/ sub 0/ are not easy. Furthermore, the relationship between the compressive load and frequency can not be determined by the conventional analytical method. The axial force-frequency relationship of sinusolidally non-symmetrically tapered members with different shapes were investigated using the finite element method. To obtain the two eigenvalues, the axial thrust was increased step by step and the corresponding frequency was calculated. The result indicated that the axial thrust of the elastic critical load ratio and the square of the frequency ratio can be approximately represented in any case by a straight line. Finally, the linear relationship is also applicable to the sinusolidally non-symmetrically tapered member.

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문화재 비파괴 분석법의 현황과 문제점 (The present condition and problems of non-destructive investigation methods for cultural property)

  • 강대일;홍종욱
    • 보존과학연구
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    • 통권19호
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    • pp.35-60
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    • 1998
  • Cultural properties are valuable objects, which have exposed insevere environment and inherited for a long time but we don’t have correct information concerning materials, structure and skill of manufacture. Because the cultural properties have been destroyed by the deterioration elements as like wind, this must be carefully treated for investigation of exhibition and storage. Even if the observation is scientific research, we must not take actual sample from the object for obtaining information concerning the nature materials and skill of manufacture. so it is elementary principle to use non-destructive investigation method as analytical methods for cultural property. This contribution discusses the present condition and problem of X-ray fluorescence acting as a representative non-destructive investigation method and the difference of statistics to be connected with determination and finally explains the intend facts for analysis of data.

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