• Journal of the Korean Ceramic Society
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• v.40 no.5
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• pp.405-409
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• 2003

The effect of substitution of Gd ions for Ca ions in the B $i_{1.84}$P $b_{0.34}$S $r_{1.91}$(C $a_{1-x}$ G $d_{x}$)$_{2.03}$ C $u_{3.06}$ $O_{ 10+{\delta}}$/ (x=0.0~0.06) was investigated by measuring x-ray diffraction patterns, lattice constants, do resistivity and Hall effect. We found the solubility limit of Gd in the 110 K phase to be x < 0.015. Within the solubility limit, the c-axis seemed to decrease with increasing x. In the region of the 110 K single phase, the critical temperature $T_{c}$ gradually decreased with an increasing the Gd concentration x, corresponding to a small change of the carrier concentration.

• BMB Reports
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• v.42 no.4
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• pp.206-211
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• 2009

Proopiomelanocortin (POMC) plays an essential role in the stress response of the hypothalamic-pituitary-adrenal axis, and is the precursor of biologically active peptides such as adrenocorticotropin (ACTH), $\alpha$-melanocyte-stimulating hormone ($\alpha$-MSH), $\beta$-melanocyte-stimulation hormone ($\beta$-MSH) and $\beta$-endorphin. We have synthesized two different forms of POMC cDNA clones, POMC-I and POMC-II, from a pituitary cDNA library for Paralichthys olivaceus, or Japanese flounder. jfPOMC-I cDNA consists of 954bp and encodes a polypeptide of 216 amino acid residues, whereas jfPOMC-II consists of 971bp which encode a polypeptide of 194 amino acid residues. The high levels of jfPOMC-I and -II mRNAs detected in the pituitary tissue and moderate levels detected in the brain tissue plus our quantitative RT-PCR analysis, which showed there to be no significant difference between the levels of jfPOMC-I and -II mRNAs, indicate that there may be no functional separation between these two mRNAs in the flounder.

• Bulletin of the Korean Space Science Society
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• 2011.04a
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• pp.30.4-31
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• 2011

The Korea Astronomy and Space Science Institute (KASI) and the Department of Astronomy at the University of Texas at Austin (UT) are developing a near infrared wide-band high resolution spectrograph, IGRINS (Immersion Grating Infrared Spectrograph). The white-pupil design of the instrument optics uses 7 cryogenic mirrors including 3 aspherical off-axis collimators and 4 flat fold mirrors. Two of the 3 collimators are H- and K-band pupil transfer mirrors and they are designed as compensators for the system alignment in each channel. Therefore, their mount design will be one of the most sensitive parts in the IGRINS optomechanical system. The design work will include the computer-aided 3D modeling and finite element analysis (FEA) to optimize the structural stability of the mount models. The mount body will also include a tip-tilt and translation adjustment mechanism to be used as the alignment compensators.

• Progress in Superconductivity
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• v.9 no.1
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• pp.107-110
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• 2007

Bi/CNT composite and resin/CNT were chosen to improve the mechanical properties of $YBa_2Cu_3O_7$(YBCO) superconductor. In order to elucidate the effects of Bi/CNT composite and resin/CNT in YBCO superconductors, melt texture superconductor were impregnated by mixed compound of Bi and CNT into the artificial holes parallel to the c-axis, which were drilled on the YBCO superconductor. Various amount of Bi/CNT and resin/CNT were impregnated to YBCO superconductor with different holes diameters. Typical artificial holes diameters were 0.5, 0.7, and 1.0 mm respectively. Result of three-point bending test measurement, the bending strength with resin/CNT impregnation was improved up to 59.64 MPa as compared with 50.79 MPa of resin/CNT free bulk. Resin/CNT impregnation has been found to be one of the effective ways in improving the mechanical properties of bulk superconductor.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2003.11a
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• pp.1251-1258
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• 2003

This paper is a study on the pedal placement and driving position of forklift according to the various body dimensions. Comfortable driving position were measured angles of joint(ankle, knee, hip) by Goniometer. From SIP(seat index point) to basis of pedals were measured about X and Y axises. In addition, Z axises were gauged between floor and pedals. In this paper, The 27 male subjects with no experience in driving forklift were measured in the test in order to exclusion of learning effect. Therefore the subjects have a preference for pedal location to the body dimensions, if as long as their body dimensions was very long, they would required each pedal's location of Y axis to increase. However, driving position is no influence. The pedal location of X and Z axises weren't related with various body dimensions and subjects have symmetrical location to the pedals of inching and break and hight of brake pedal is lower than the others. They hope that brake pedal is lower than others.

• Advances in materials Research
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• v.1 no.3
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• pp.169-182
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• 2012

In this paper the intrinsic influence of micron-sized nickel particle reinforcements on microstructure, micro-hardness tensile properties and tensile fracture behavior of nano-alumina particle reinforced magnesium alloy AZ31 composite is presented and discussed. The unreinforced magnesium alloy (AZ31) and the reinforced nanocomposite counterpart (AZ31/1.5 vol.% $Al_2O_3$/1.5 vol.% Ni] were manufactured by solidification processing followed by hot extrusion. The elastic modulus and yield strength of the nickel particle-reinforced magnesium alloy nano-composite was higher than both the unreinforced magnesium alloy and the unreinforced magnesium alloy nanocomposite (AZ31/1.5 vol.% $Al_2O_3$). The ultimate tensile strength of the nickel particle reinforced composite was noticeably lower than both the unreinforced nano-composite and the monolithic alloy (AZ31). The ductility, quantified by elongation-to-failure, of the reinforced nanocomposite was noticeably higher than both the unreinforced nano-composite and the monolithic alloy. Tensile fracture behavior of this novel material was essentially normal to the far-field stress axis and revealed microscopic features reminiscent of the occurrence of locally ductile failure mechanisms at the fine microscopic level.

• Journal of the Korean Institute of Educational Facilities
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• v.19 no.3
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• pp.33-40
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• 2012

At present, the problem to secure seismic resistance capacity is one of the most important issue in school buildings. However, the range of facilities to consider retrofit or the proper direction of seismic retrofit haven't provided in details. Therefore in this study, a series of school buildings were chosen as established time, and the structure composition and the seismic performance of the school buildings were investigated to get the comprehensive features of seismic resistance capacity in school buildings. At result, it was presented that the member capacities were less than criteria and structure system was showed the brittle behavior at the collapse prevention level at the school buildings before 1990 year. At the school buildings after 1990 year, though it is hard to get general features for various compositions, it was presented that they have problems for seismic performance evaluation in some buildings at life safety level, specially in the direction of X axis. So, considering the introduction process of seismic criteria in Korea, the school buildings before 2005 year should be examined for seismic resistance capacity and the seismic performance should be examined as well as member capacity to resist seismic.

• Journal of radiological science and technology
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• v.21 no.2
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• pp.5-10
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• 1998

In the mammography, X-ray beam quality is one of the most important factors. Using X-ray mammography unit model GE/CGR Senography 600T Senix H.F, Authors studied four subjects. 1. The aluminum attenuation rate in 30 kVp when used with or without compression plate. 2. HVLs at 5 different area of the X-ray field of $26{\sim}32kVp$. 3. HVLs to know the influence of corrected measurement or parallel measurement. 4. Film density with microdensitometer along and cross to the long axis of X-ray tube, in terms of the Heel effect in the X-ray field. The following results were obtained. 1. Beam quality of anode area was harder than cathode area. 2. The dose reduction rate of compression plate was approximately $65.5%{\sim}88.1%$ and the beam quality with compression plate was hardened up to 4kVp accordingly. 3. If the X-ray beam enters the attenuation plate obliquely, HVL was $2.6{\sim}2.9%$ harder than perpendicular to it. 4. Because of heel effect, the film density of cathode area is higher than anode area to film density of 0.5.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.580-585
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• 2005

A QRT(Quad-Rotor Type) hovering robot system is developed for quick detection and observation of the circumstances under calamity environment such as indoor fire spots. The UAV(Unmanned Aerial Vehicle) is equipped with four propellers driven by each electric motor, an embedded controller using a DSP, INS(Inertial Navigation System) using 3-axis rate gyros, a CCD camera with wireless communication transmitter for observation, and an ultrasonic range sensor for height control. The developed hovering robot shows stable flying performances under the adoption of RIC(Robust Internal-loop Compensator) based disturbance compensation and the vision based localization method. The UAV can also avoid obstacles using eight IR and four ultrasonic range sensors. The VTOL(Vertical Take-Off and Landing) flying object flies into indoor fire spots and sends the images captured by the CCD camera to the operator. This kind of small-sized UAV can be widely used in various calamity observation fields without danger of human beings under harmful environment.

• Journal of Magnetics
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• v.11 no.4
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• pp.182-188
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• 2006

The search for high-density recording materials has been one of most active and vigorous field in the field of magnetism. $FePt-L1_{0}$ nanoparticle has emerged as a potential candidate because of its high anisotropy. In this paper, we provide an overview of recent work at Argonne National Laboratory that contributes to the ongoing dialogue concerning the relation between structure and properties of the FePt nanoparticle system. In particular we discuss the ability to control structure and properties via dosing with Cr. Cr-dosed FePt films were grown via molecular beam epitaxy and annealed at $550^{\circ}C$ in an ultrahigh vacuum chamber, and were studied with the surface magneto-optic Kerr effect (SMOKE), scanning electron microscopy (SEM) and x-ray magnetic circular dichroism (XMCD). We found that small dosage of Cr helps to generate $L1_{0}$ phase FePt magnetic nanoparticles with small size, defined shape and regular spatial distribution on MgO (001) substrate. The nanostructures are ferromagnetic with high magnetic coercivity (${\sim}0.9T$) and magnetic easy axis in the desired out-of-plane orientation. We also show that controlling the lateral region where nanostructures exist is possible via artificial patterning with Cr.