• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.140-142
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• 2003

ZnO thin films are demanded for device applications, so ZnO buffer layer was used to improve for good properties of ZnO thin film. In this study, the structural, electrical and optical properties of ZnO thin films deposited with various buffer thickness was investigated by X-ray diffraction (XRD), Hall measurements, Photoluminescence(PL). ZnO buffer layer and ZnO thin films on sapphire($Al_{2}O_{3}$) substrate have been deposited $200^{\circ}C$ and $400^{\circ}C$ respectively by pulsed laser deposition. It is observed the variety of lattice constant of ZnO thin film by (101) peak position shift with various buffer thickness. It is founded that ZnO thin film with buffer thickness of 20 nm was larger resistivity of 200 factor and UV/visible of 2.5 factor than that of ZnO thin films without buffer layer. ZnO thin films with buffer thickness of 20 nm have shown the most properties.

• Journal of the Korean Society of Costume
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• v.58 no.7
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• pp.31-42
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• 2008

The fashion of the 19C had been through many diverse styles, i.e. Empire style, Romantic style, Crinoline style and the Bustle style. These styles had emphasized a certain figures, such as exaggerated hourglass silhouette of crinoline style or S silhouette of bustle style. Following the trends, corsets became more than underwears. Actually they supported the fashion of the 19C. Apparently, the corsets had been evolved in many aspects. Patterns, materials and trimmings were developed and refined to make torso figures desirable. The initial purpose of the research is to find out how they developed corset patterns to make such a diverse figures, so that the techniques can be adopted in contemporary pattern design. The 16 corsets and their patterns were quoted from books related the subject. The patterns were redrawn of same scale for the comparative study concerning cutting lines and measurements. Coming to the late, more curved lines and more segmented cutting were used to make body more of glamour and natural. Gussets were another key technique to make them work. Various sized and shaped gussets were used to follow the trends of ever changing.

• Proceedings of the Korean Fiber Society Conference
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• 1987.06b
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• pp.11-11
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• 1987

Among other poly(4,4'-terephthanilidealkylamide)s (PTAA's), poly (4,4'-terephthanilideadipamide) (PTAd) gave clear critical concentration curves. For PTAA's with methylene units more than 6, the critical concentration (C*) seemed to be beyond the solubility limit of H₂SO₄. Under shearing conditions, the nematic domains were easily oriented and stretched in the direction of shear , and a fibrillar structure resulted. At low frequencies, a monotollous reduction of loss tangent (tan) was observed as concentration increased. At high frequencies, however, tan was increased above C* again, and showed maximum at saturation concentration (Cs). With increasing temperature, viscosity of isotropic and anisotropic phases was normally decreased, while viscosity of biphases was increased. Plot of complex viscosity (If) against temperature based on rheological measurements exhibited a good correlation with phase diagram constructed by polarizing microscope observations. Rheological parameters suggested the optimum dope concentration of PTAd with inherent viscosity 2.02 at 30oc is in the vicinity of 19.2 wt%, which seemed to agree well with spinning experiments (around 19.4 wt%). In general, effects of spinning and annealing conditions on the mechanical properties of PTAA fibres were most pronounced in PTAd fibre spun from anisotropic spinning dope .

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.191-195
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• 2005

We used Subaru observations of A1689 (z = 0.183) to derive an accurate, model-independent mass profile for the entire cluster, r$\le$2Mpc/h, by combining magnification bias and distortion measurements. The projected mass profile steepens quickly with increasing radius, falling away to zero at r${\~}$1.0Mpc/h, well short of the anticipated virial radius. Our profile accurately matches onto the inner profile, r $\le$200kpc/ h, derived from deep HST / ACS images. The combined ACS and Subaru information is well fitted by an NFW profile with virial mass, $(1.93 \pm 0.20) {\times}10^{15} M_{\bigodot}$, and surprisingly high concentration, $C_{vir} = 13.7^{+1.4}_{-1.1}$, significantly larger than theoretically expected ($C_{vir} {\le}4$), corresponding to a relatively steep overall profile. These results are based on a reliable sample of background galaxies selected to be redder than the cluster E/SO sequence. By including the faint blue galaxy population a much smaller distortion signal is found, demonstrating that blue cluster members significantly dilute the true signal for r $\le$ 400kpc/ h. This contamination is likely to affect most weak lensing results to date.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.1
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• pp.7-11
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• 2006

Through SCM modeling, we found that the depletion layer in silicon was of a form of a spherical capacitor with the SCM tip biased. Two-dimensional (2D) finite differential method code with a successive over relaxation (SOR) solver has been developed to model the measurements by SCM of a semiconductor wafer that contains an ion-implanted impurity region. Then, we theoretically analyzed the spherical capacitor and determined the total depleted-volume charge Q, capacitance C, and the rate of capacitance change with bias dC/dV. It is very important to observe the depleted carriers' movement in the silicon layer by applying the bias to the tip. So, we calculated the depleted-volume charge, considering different factors such as tip size, oxide thickness, and applied bias (dc+ac), which have an influence on potential and depletion charges.

• Journal of the Mineralogical Society of Korea
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• v.15 no.3
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• pp.161-169
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• 2002

high pressure and temperature conditions. However, those results are not consistent with one another, and phase boundary between ilmenite and perovskite phases determined only from the quenching method may be not so reliable at all. Therefore, in-situ high pressure-temperature (hP-T) X-ray diffraction measurements were performed up to 19 GPa and $700^{\circ}C$ in a large volume press apparatus using synchrotron radiation. Experimental results show that perovskite phase is stable at pressures above 16 GPa, and transforms back to $LiNbO_3$phase near 15 CPa at room temperature, and that the perovskite-ilmenite transition is back and forth near 15 CPa at $500^{\circ}C$. LiNbO$_3$phase transforms to ilmenite at 13 CPa and $300^{\circ}C$ and at 10.8 CPa and $400^{\circ}C$, respectively. These data indicate that $LiNbO_3$phase may have a stability region in the hP-T phase diagram and that the perovskite-ilmenite phase boundary would be quite different from that previously reported.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.3 s.162
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• pp.343-350
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• 2007

This study compared and studied the clothing mobility of two types of aerobic clothes - those made of currently popular stretch materials and those made of new stretch materials that were specially developed for this study. The focus of the comparison was on the range of joint movement during activity, and the physiological burden imposed on the body by the clothes. In total, 18 experiments were carried out under controlled conditions in an artificial climatic chamber with a temperature of $25{\pm}1^{\circ}C$, air humidity of $60{\pm}5^{\circ}C$ and negligible air movement. Each exercise program consisted of a 30-minute of aerobic workout and a 20-minute rest following the exercise. Measurements were taken to determine the following: physiological reactions (whole-body and local sweat rates), subjective sensations(of temperature, humidity, comfort, tightness, and clothing wetness), joint angle(measured with a goniometer), and so on. The results of the study us as follows: Material B excels in clothing mobility. Material C excels in sweat absorbency and drying speed. Material A was found to be the hottest material, while material C was found to be slightly hot through the analysis of the change in pre- and post-exercise bodyweight(= amount of sweat). Regarding the amount of evaporated sweat, material A>material C>material B. Material B produced the smallest amount of evaporated sweat. The wider the range of joint movement, the smaller the amount of sweat and the lower the average skin temperature.

• Journal of Electrochemical Science and Technology
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• v.4 no.1
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• pp.34-40
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• 2013

The structural and electrochemical properties of $Li_{0.99}Ni_{0.46}Mn_{1.56}O_4$ ($Fd{\bar{3}}m$, disordered spinel) cathode material were studied and compared with stoichiometric $LiNi_{0.5}Mn_{1.5}O_4$ ($P4_332$, ordered spinel). First cycle discharge capacity of $Li_{0.99}Ni_{0.46}Mn_{1.56}O_4$ was similar to that of $LiNi_{0.5}Mn_{1.5}O_4$ at C/3 and 1C rate, but cycling performance of $Li_{0.99}Ni_{0.46}Mn_{1.56}O_4$ was better than that of $LiNi_{0.5}Mn_{1.5}O_4$ especially at high rate of 1C. This can be explained by performing synchrotron based in-situ XRD and results of GITT measurements. It is considered that faster lithium ion diffusion in the $Li_{0.99}Ni_{0.46}Mn_{1.56}O_4$ cathode results in the improvement of the rate capability. To study structural changes during cycling, synchrotron in-situ XRD patterns of both the samples were recorded at C/3 and 1C rate. Compared to stoichiometric $LiNi_{0.5}Mn_{1.5}O_4$, disordered $Li_{0.99}Ni_{0.46}Mn_{1.56}O_4$ spinel sample has pseudo one phase behavior and one step phase transition between two cubic phases. So, $LiNi_{0.5}Mn_{1.5}O_4$ would experience a much greater strain and stress, originating from the two phase transitions between three cubic phases and suffer from capacity loss during cycling especially at high rate.

• Asian Journal of Atmospheric Environment
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• v.6 no.2
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• pp.83-95
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• 2012

China has been a top producer and exporter of refined lead products in the world since the year 2000. After the phasing-out of leaded gasoline in the late 1990s, non-ferrous metallurgy and coal combustion have been identified as potential major sources of aerosol lead in China. This paper presents the single particle analytical results of ambient aerosol particles collected near a lead smelter using a scanning electron microscopy- energy dispersive x-ray spectroscopy (SEM-EDX). Aerosol particle samples were collected over a 24-hour period, starting from 8 pm on 31 May 2002, using a high volume TSP sampler. For this near source sample, 73 particles among 377 particles analyzed (accounting for 19.4%) were lead-containing particles mixed with other species (S, Cl, K, Ca, and/or C), which probably appeared to be from a nearby lead smelter. Lead-containing particles of less than $2{\mu}m$ size in the near source sample were most frequently encountered with the relative abundances of 42%. SEM-EDX analysis of individual standard particles, such as PbO, PbS, $PbSO_4$, $PbCl_2$, and $PbCO_3$, was also performed to assist in the clear identification of lead-containing aerosol particles. Lead-containing particles were frequently associated with arsenic and zinc, indicating that the smelter had emitted those species during the non-ferrous metallurgical process. The frequently encountered particles following the lead-containing particles were mineral dust particles, such as aluminosilicates (denoted as AlSi), $SiO_2$, and $CaCO_3$. Nitrate- and sulfate-containing particles were encountered frequently in $2-4{\mu}m$ size range, and existed mostly in the forms of $Ca(NO_3,SO_4)/C$, $(Mg,Ca)SO_4/C$, and $AlSi+(NO_3,SO_4)$. Particles containing metals (e.g., Fe, Cu, and As) in this near source sample had relative abundances of approximately 10%. Although the airborne particles collected near the lead smelter contained elevated levels of lead, other types of particles, such as $CaCO_3$-containing, carbonaceous, metal-containing, nitrates, sulfates, and fly-ash particles, showed the unique signatures of samples influenced by emissions from the lead smelter.

• Progress in Medical Physics
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• v.28 no.4
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• pp.190-196
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• 2017

For the $ViewRay^{(R)}$ system (ViewRay Inc., Cleveland, OH, USA) which is representative of magnetic resonance (MR) guided radiotherapy machine, it is important to evaluate effectiveness of AAPM's TG-51 protocol and the effect of the magnetic field on absolute dosimetry. In order to measure the absolute dose, MR-compatible chamber and water phantom system manufactured in this study were used. The materials of the water phantom system were plastic of polymethyl methacrylate (PMMA) and non-ferrous materials. Due to the inherent feature of the $ViewRay^{(R)}$, all Co-60 sources are not located at gantry angle of $0^{\circ}$ while being located at gantry angle of $90^{\circ}$. For this reason, absolute dosimetry was performed based on the measurements in solid water phantom (SWP) and water which determine the SWP to water correction factor. For evaluation of output constancy with gantry angle, measurements were made with ionization chamber inserted in cylindrical water-equivalent phantom. For measured doses in water, the values of dose deviation according to a reference dose of 200 cGy for Head 1, Head 2 and Head 3 were -0.27%, -0.45% and -0.22%, respectively. For measured doses in SWP, the values of dose deviation according to a reference dose of 200 cGy for Head 1, Head 2 and Head 3 were -1.91%, -2.07% and -1.84%, respectively. All values of dose measured in SWP tended to be less than those measured in water by -1.63%. With the reference gantry angles of $0^{\circ}$ and $90^{\circ}$, the maximum values of deviation for Head 1, Head 2 and Head 3 were 0.48%, 1.06% and 0.40%, respectively. The measurement agreement is within the range of results obtainable for conventional treatment machines. The low strength of the magnetic field does not affect dose measurements. Using the SWP to water correction factor, absolute doses for $ViewRay^{(R)}$ system can be measured.