• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 하계학술대회 논문집
• /
• pp.515-518
• /
• 2002

In this study, the ellipsoidal cap type magnetic pole structure was proposed for the electro-magnet in B-H curve tracer. From the simulation for the electro-magnet without specimen, the area of effective uniform field(99% range for the central field value) was considerably increased in case of the newly proposed ellipsoidal cap type magnetic pole than that of the conventional simple-inclined cap type magnetic pole. Also, through the simulation for the electro-magnet with permanent magnet specimen(NaFe30), the optimal Positions of the magnetic field measurement sensor(Hall sensor) were found out in each case and the errors were decreased in case of the newly proposed ellipsoidal cap type magnetic pole.

• Journal of Magnetics
• /
• 제2권3호
• /
• pp.72-75
• /
• 1997

The temperature dependent saturation magnetization curve of amorphous Fe67 Co18B14Si1, alloy was measured using a SQUID magnetometer and vibrating sample magnetometer from 5 K up to 800 K. Inelastic neutron neutron scattering measurements also have been used to study the long wavelength spin dynamics of this high Tc amorphous ferromagnetic alloy. The magnon dispersion curve exhibit the conventional quadratic relationship E = D (T) q2 + $\Delta$, typical of an iso=obtained from a low temperature magnetization curve, which was consistent with the value obtained from the analysis oif inelastic neutron scattering data after consideration of its temperature dependence.

• 한국전기전자재료학회논문지
• /
• 제16권12S호
• /
• pp.1305-1309
• /
• 2003

To utilize FeCoSiB amorphous films for magnetoelastic sensors, the temperature dependency of magnetization (M-T curve) and the magnetization properties of the amorphous films were investigated in this study. As the amount of cobalt In the films increased, the Curie temperature decreased but the crystallization temperature increased. In addition to this, the crystallization temperature was lower than the Curie temperature in the film containing 20 at% cobalt. The optimized annealing condition was set up by analyzing the H-T curve. And then, the amorphous film that has excellent magnetic properties and uni-axal anisotropy could be prepared for construction of the magnetoelastic sensor devices. The coercive force of the film was below 0.5 Oe and the anisotripic field was about 5 Oe.

• 대한조선학회논문집
• /
• 제35권4호
• /
• pp.118-125
• /
• 1998

본 연구는 B-spline 근사법과 유전자 알고리즘을 이용하여 기하학적 경계 조건-양끝점의 위치 벡터 및 접선 벡터-을 만족하는 혼합 곡선 근사법에 의한 선형 표현을 내용으로 한다. B-spline 근사법을 이용하여 선형을 표현하고, 이들 곡선을 제어하는 조정점들이 기하학적 경계조건을 만족하도록 유전자 알고리즘으로 조정한다. 이 방법은 선형 생성시 순정 작업을 동시에 수행하므로 효율적인 선형 설계를 가능하게 한다.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2003년도 추계학술대회논문집
• /
• pp.318-321
• /
• 2003

In order to generate the extrusion die surface of non-symmetric H- and U-shaped sections, an automatic surface construction method based on B-spline surface and scalar field theory is proposed in this study. The isothermal lines and stream lines designed in the scalar field are introduced to find the control points which are used in constructing B-spline surfaces. Intersected points between the isothermal lines and stream lines are used to construct B-spline surfaces. The inlet and outlet profiles are precisely described with B-spline curves by using the centripetal method for uniform parameterization. The extrusion die surface is generated by using the cubic curve interpolation in the u- and v-directions. A quantitative measure for the control of surface is suggested by introducing the tangential vectors at the inlet and outlet sections.

• Biomolecules & Therapeutics
• /
• 제2권2호
• /
• pp.114-119
• /
• 1994

[$^3$H]Ouabain binding parameters ( $K_{D}$ and $B_{max}$) to control rat ventricular strips and Langendorff preparations which were not previously exposed to ouabain were compared with those to both preparations that had been first exposed to a complete ouabain dose range of dose-response curve (10$^{-8}$ to 10$^{4}$M). In rat ventricular strips and Langendorff perfused heart preparations, cumulative dose-response curves of ouabain revealed biphasic positive inotropic effects, a "low-dose" effect and a "high-dose" effect with E $d_{50}$ values of 0.5 $\mu$M and 35 $\mu$M ouabain, respectively. The "low-dose" effect in ventricular strip disappeared or was diminished significantly when the ouabain dose-response curve was repeated after the washout of the effects of the first dose-response curve, whereas there were no significant differences in the maximal "high-dose"effect in both exposures to oubain. However, both of the control and ouabain-preexposed Langendorff perfused hearts revealed the same low-dose effects. The $K_{D}$ value for [$^3$H] ouabain binding and the ouabain binding site concentration ( $B_{max}$) estimated by [$^3$H]ouabain displacement assay in control preparations were 230 nM and 2 pmol/mg protein, respectively. [$^3$H]Ouabain binding parameters were not changed by repeated exposure to high concentrations of ouabain. These results suggest that digitalis receptor desensitization in the rat ventricular strip may due to the change of post-receptor events induced by ouabain binding to a high affinity site ($\alpha$$_2$isoform).).).).).

• 한국자기학회지
• /
• 제7권6호
• /
• pp.327-333
• /
• 1997

페라이트, 비정질 코아등의 고주파 연자성재료의 고주파 자기특성 데이터를 디지타이징 방법으로 얻고, 철손 및 B-H 곡선, 투자율을 자동적으로 측정할 수 있는 고주파 자기특성측정장치를 제작하였다. 본 시스템은 교류 인가를 위한 신호발생기와 전력증폭기, 인가자장을 게측하기 위한 전류측정용 저항, H 및 B 신호를 디지타이징 (digitizing)하기 위한 대역폭 500 MHz, 샘플링속도 1 Gs/s의 디지털 오실로스코프, 시스템 제어에 사용되는 GPIB 케이블 및 퍼스널 컴퓨터로 구성되었다. 자계 H 계측을 위한 전류센서로서 저항기(resistor)와 Rogowski 코일을 비교 검토한 결과 고주파 변류기 (current transformer : 이하 CT)가 주파수 특성과 노이즈 억제효과에서 보다 우수하였다. 측정시스템에 동작자속밀도 설정, 비대칭 B-H 곡선의 보정, 구형파등의 다양한 파형지원등의 기능을 부가하였다.

• Journal of Magnetics
• /
• 제6권2호
• /
• pp.61-65
• /
• 2001

The Hopkinson effect in the HDDR-treated $Nd_{15}Fe_{77}B_8$ allay was examined in detail by means of a thermo-magnetic analysis with low magnetic field (600 Oe). The emergence and magnitude of maximum in magnetisation in the thermomagnetic curve due to the Hopkinson effect was correlated with the grain structure and coercivity of the HDDR-treated material. The HDDR-treated materials showed a clear Hopkinson effect (maximum in magnetisation just below the Curie temperature of the $Nd_2Fe_{14}B\;$ phase) on heating. The magnitude of the magnetisation rise due to the Hopkinson effect became smaller as the recombination time increased. The magnetisation recovery at room temperature on cooling from above the Curie temperature became smaller as the recombination time increased. The HDDR-treated materials with shorter recombination time, finer grain size and higher coercivity showed larger magnetisation maximum due to the Hopkinson effect in the thermo-magnetic curve.

• 대한수학회논문집
• /
• 제33권4호
• /
• pp.1309-1320
• /
• 2018

In this paper, we show that proper biharmonic spacelike curve ${\gamma}$ in Lorentzian Heisenberg space (${\mathbb{H}}_3$, g) is pseudo-helix with ${\kappa}^2-{\tau}^2=-1+4{\eta}(B)^2$. Moreover, ${\gamma}$ has the spacelike normal vector field and is a slant curve. Finally, we find the parametric equations of them.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
• /
• 한국우주과학회 2003년도 한국우주과학회보 제12권2호
• /
• pp.24-24
• /
• 2003

We present preliminary results about the quasi-simultaneous near-infrared light curves of the long-period eclipsing polar V1309 Ori in the J, H, K', and K bands with almost complete orbital phase coverage using the CFHT-IR camera. The optical light curve in the V and R bands, obtained by 1.8m Telescope at BOAO, will be also presented. The shape and the amplitude of the orbital light curve change significantly from optical to near-infrared wavelengths.