• Journal of the Korean Magnetics Society
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• v.4 no.3
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• pp.233-238
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• 1994

The effect of die upset and heat treatment on the magnetic properties of mechanically ground $Nd_{16}Fe_{78}B_{6}$ alloys has been studied. Although stripe domain patterns parallel to the compression direction were observed after die upset, it was found that crystallographic c-axes of a specimen were not completely aligned along the compression direction' which resulted in the decrease of Br. The average grain size of a die-upset specimen annealed for 5 hours at $1000^{\circ}C$ was about $20\mu\textrm{m}$, resulting in reduced values of Br and $_{i}H_{c}$. The maximum magnetic properties (Br=7.8 kG and $(_{i}H_{c}=14\;kOe) were obtained from the magnet die-upset at $750^{\circ}C$ using the alloy powder ground for 13 hours.

• Korean Journal of Crystallography
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• v.5 no.1
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• pp.1-6
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• 1994

Two possible space groups of the comfound, VP6N3018C24H:60, are: P 1, a=14.022(1), b=12.644(2), c= 12.640(1)A, a=8038(1), B=102.12(1), r=102.16(1), V=2124.1A3, Z=2, μ=0.47cm-1, d=1.46g/cm3, R=0.083 for 3350 independent reflections with Fo>4o IFI, and C2/c, a=19.32(2), b=16.32(2), c=14.02(1)A, B=105.98(5), β=105.98(5), V=4248.2A3, Z=4 R=0.083 for 1590 independent reflections with Fo>4c IFoI . In the space group P T, there are two monlecules in a unit cell. Vanadium atoms in the two monlecules occupy the two different special positions such that the complete monlecules are accomplished by the two independent center of symmetry. Therefore two different half molecules of bis(trimetaphosphate)vanadate and three molecules of tetraethylammonium are the asymmetric unit in a unit cell. In the space group C2/c, however, the vanadium atom is located at a special position with centrosymmetry, and a two-fold symmetry axis passes through C2/c, N2 and C25 atoms. Therefore the asymmrtic unit in a unit cell consists of a half molecule of bis(trimetaphosphate)vanadate and one and a half molecules of tetraethylammonium. All the molecular conformations in both space groups are very similar: six oxygen atoms coordinated to a vanadium atom in the bi s(trimetaphosphate)vanadate molecule form an octahedron and the four carbon atoms bonded to a nitrogen atom in the tetraethylammonium molecule are disordered so that the eight carbon atoms around nitrogen atom exhibit an irregular dodecahedral form.

• Electronics and Telecommunications Trends
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• v.14 no.2 s.56
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• pp.69-82
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• 1999

본 고에서는 ATM 기반망의 PNNI 규격인 B-ISUP과 PNNI 규격의 특성을 비교, 분석하고 국내 초고속정보통신망에의 적용성을 분석하였다. 지금까지 WAN을 비롯한 대부분의 ATM 망은 PVC 기반으로 동작하도록 구축, 운용되고 있으나, 한편으로는 사용자가 요구한 다양한 호, 연결의 설정과 해제를 on-demand로 지원할 수 있는 SVC 능력이 요구되고 있는 실정이다. ATM 망에서 SVC 기반 서비스를 제공하기 위해서는 on-demand 호/연결 제어를 위한 UNI와 NNI 신호능력이 제공되어야 한다. ATM 망의 NNI 규격으로는 ITU-T의 B-ISUP 규격과 ATM Forum에서 정의한 PNNI 규격이 고려될 수 있다. B-ISUP과 PNNI 규격은 각기 공중망과 사설망에의 적용을 목표로 만들어졌으므로 두 규격간에는 여러 가지 면에서 서로 상이한 점이 많다. B-ISUP 프로토콜은 동적 라우팅보다는 망운용자의 제어에 의한 계획된 라우팅이 요구되는 망에 적합하며 상대적으로 신뢰성이 우수하고 구조가 단순하다. 이에 비해 PNNI는 토폴로지나 주소체계 등이 자주 바뀌는 경우 자동적 업데이트가 지원되며 QoS 지원이 가능한 동적 라우팅 능력을 갖는 대신에, 상대적으로 복잡하고, 신뢰성 있는 연결 제어가 미흡하다. 본 고에서 분석한 내용은 우리나라 초고속정보통신망의 NNI 규격 적용의 기준 정립을 위한 참고자료로 활용될 수 있다.

• Journal of Magnetics
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• v.2 no.3
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• pp.72-75
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• 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.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1721-1724
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• 2013

Objective: To investigate the effect of epirubicin on soluble CD25 (sCD25) secretion by CD4+CD25+ regulatory T (Treg) cells isolated from diffuse large B-cell lymphoma (DLBCL) patients. Methods: Treg cells were isolated from the peripheral blood mononuclear cells isolated from the newly diagnosed DBLCL patients. The concentration of sCD25 in the supernatant was determined with a commercial sCD25 (IL-2R) enzyme-linked immunosorbent assay (ELISA) kit. The fluorescence intensity of CD25 was detected by flow cytometry. Results: Cell survival rate was significantly decreased along with the increase of epirubicin concentration after treatment for 24 h. There was also a significant difference in the concentration of sCD25 between the epirubicin group and the control group (P<0.01). A positive correlation between the Treg cells survival rate and the concentration of sCD25 was detected (r=0.993, P<0.01). When equal numbers of CD4+CD25+ Treg cells of the epirubicin group and the control group were cultured for another 24 h without epirubicin the CD25 fluorescence intensity on the surface of Treg cells was obviously higher in the epirubicin group than that in the control group (P<0.01), while the sCD25 concentration in the supernatant in the epirubicin group was significantly lower than that in the control group (P<0.05). Conclusion: Epirubicin may improve the body's immune functions by inhibiting the sCD25 secretion by Treg cells in DLBCL patients.

• Journal of Biomedical Engineering Research
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• v.21 no.3 s.61
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• pp.303-309
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• 2000

An accurate quantitative biomechanical evaluation for the spasticity caused by the disorder of central nervous system was made in this study. A sudden leg dropper was designed to generate objective testing environment at every trial. 3-dimensional motion analysis system(Elite. B.T.S. Italy) was used to measure kinematic data which were angle. and angular velocity of a lower limb. A program was developed to analyze the kinematic data of lower limb motion. and dynamic EMG data at the same time. To evaluate spasticity quantitatively. total 26 parameters including 14 parameters newly driven were analyzed, and statistical analysis were made for bilateral correlations. Results showed possibility to make accurate quantitative and objective evaluation for spasticity with various new parameters using new devices and program.

• Journal of the Korean Magnetics Society
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• v.16 no.6
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• pp.279-282
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• 2006

Magnetic tunnel junctions (MTJs), which consisted of amorphous ferromagnetic NiFeSiB free layers, were investigated. The NiFeSiB layers were used to substitute for the traditionally used CoFe and/or NiFe layers with the emphasis being given to obtaining an understanding of the effect of the amorphous free layer on the switching characteristics of the MTJs. $Ni_{16}Fe_{62}Si_{8}B_{14}$ has a lower saturation magnetization ($M_{s}:\;800\;emu/cm^{3}$) than $Co_{90}Fe_{10}$ and a higher anisotropy constant ($K_{u}:\;2700\;erg/cm^{3}$) than $Ni_{80}Fe_{20}$. The $Si/SiO_{2}/Ta$ 45/Ru 9.5/IrMn 10/CoFe $7/AlO_{x}/CoFeSiB\;(t)/Ru\;60\;(in\;nanometers)$structure was found to be beneficial for the switching characteristics of the MTJ, leading to a reduction in the coercivity ($H_{c}$) and an increase in the sensitivity resulted from its lower saturation magnetization and higher uniaxial anisotropy. Furthermore, by inserting a very thin CoFe layer at the tunnel barrier/NiFeSiB interface, the TMR ratio and switching squareness were improved more with the increase of NiFeSiB layer thickness up to 11 nm.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.2
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• pp.104-115
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• 1989

In an effort to clarify the wetted patterns of sandy loam soil under trickle irrigation conditions, the distance of wetted zone, infiltration capacity and soil wetted patterns, etc. were measured by gypsum block as soil moisture sensor located every 5 cm vertically and horizontaly in the soil bin under the such conditions as a). irrigation rates set to 2, 4, 6, 8 liters per hour b). total amount of water applied fixed to 14.62 liters per soil bin c) the hearing force of soil measured by plate penetrometer ranging from 1.04 to 1.22kg/cm$_2$ The results can be summarized as follows ; 1. The wetted distance in horizontal direction(H), the wetted distance in vertical direction(D), the horizontal infiltration capacity (iH) and the vertical infiltration capacity(in)could by explained as a function of time t. 2. The horizontal wetted distance (H) is explained by an exponetial function H= a$.$ t where b was found ranging from 021 to 026 under surface trickle irrigation, which was considered a lotlower than the classical value of 0.5 and these measurements were indifferent to the increasing irrigation rates. 3. As for the surface trickle irrigation where horizontal infiltration capacity(iH) is explained as iH = A $.$ t h, the coefficient A increases with respect to irrigation rates within the limits of 0.89~1.34. 4. In terms of surface trickle irrigation of the ratio of Dm Which is maximum vertical wetted distance to Hm, which is maximum horizontal wetted distance, found to be within range of 1.0 to 1.21. It was also noted that the value of Dm decreses when irrigation rates increases while the value of Hm changes the opposite direction. 5. The optimum location of sensors from emitter for surface trickle irrigation should he inside of hemisphere whose lateral radius is 28~30cm long and vertical radius is 10~12cm long. The distance between emitters should be within 60cm long. 6. In the study of vertical wetted distance( D) where D= a $.$ tb, the exponential coefficient b ranged from 0.61 to 0.75 in surface trickle irrigation, and from 0A9 to 0.68 for subsurface trickle irrigation. These measurements showed an increasing tendency to with respect to irrigation rates. 7. In case of vertical infiltration capacity( in), where iD= A $.$ t 1-h, the coefficient A for surface trickle irrigation found to be within range of 0.16 to 0.19 and did not show any relationships with varying degree of irrigation rates. However, the coefficient was varying from 0.09 to 0.22 and showed a tendency to increase vis-a-vis irrigation rates for subsurface trickle irrigation, in contrast. 8. In the observation of subsurface trickle irrigation, it was found that Dm/Hm ratio was within 1.52 to 1.91 and showed a decreasing tendency with respect to increasing rates of irrigation. 9. The location of sensors for subsurface trickle irrigation follows same pattern as above, with vertical distance from emitter being 10~17cm long and horizontal 22~25cm long. The location of emitter should be 50 cm. 10.The relationship between VS which is the volume of wetted soil and Q which is the total amount of water when soil is reached field capacity could be explained as VS= 2.914Q0.91and the irrigation rates showed no impacts on the above relationship.

• Korean Journal of Poultry Science
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• v.35 no.2
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• pp.171-176
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• 2008

Animal welfare advocates, claim that the induced molting by fasting be avoided. This study was conducted to evaluate the effect of molting induced by various feeding methods on productivity and egg quality in laying hens. We used 400 flocks of 60-week-old leghorn laying hens in four treatments(five replicates of 20 hens each): fasting method (C), feeding single corn grain diet (T1), feeding single wheat bran diet (T2) and feeding single alfalfa meal diet (T3). As the result of the experiment, egg production and daily egg mass significantly decreased only in T1 compared with the control during the $1{\sim}4th$ week after the secondary egg laying (P<0.05). Although the amount of feed intake was significantly less in T1 group during the $1{\sim}4th$ week compared to the control, no significant difference was detected during the total period (P>0.05). In addition, no significant difference of feed conversion was observed between treatment groups. In terms of egg quality, the egg shell thickness was significantly improved in T1 group than the control group by feeding only corn at the 10th and 14th week after the secondary egg laying (P<0.05), but the significant decrease was observed at the corn (T1) and wheat bran (T2) fed treatment groups than the control group at the 26th week of the experiment (P<0.05). The eggshell strength and haugh unit did not show any difference by the molting methods. Egg yolk color was significantly decreased in T1 and T2 group than the control group at the 6th week (P<0.05). However, T1 and T2 group resulted to show significantly high egg yolk color at the 18th week of the experiment (P<0.05). As the result of the experiment, no large difference was observed in the productivity by the feeding molting method and by the fasting induced molting method. In addition, the single diet fed feeding induced molting method by using alfalfa revealed to show more satisfactory trend than the corn or wheat bran single diet fed feeding induced molting methods even if no statistically significant difference was found in terms of egg productivity.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.10-14
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• 1989

This paper shows an experimental study of home appliance motor noise, also represents some relations between skew-types and skew-angles. Frequency analysis was made for stator and rotor harmonic fluxes. making use of searching coils. Besides electrical analysis, mechanical noise trans mission analysis are studied to lee how they affected on the noise of the motor. Finally, we proved the noise sources of the motor using sound intensity method.