• Korean Journal of Optics and Photonics
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• v.5 no.4
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• pp.481-486
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• 1994

We demonstrate z-scan method as a tool for investigating the molecular orientational order in organic solution when high static electric field is applied. Experiments are performed for the solution of 0.5% (by weight) 4-dimethylamino-4'-nitrostilbene in cyclopentanone and nonlinear refractive index $n_{2}$, is measured to be $-0.905\times10^{-8}\textrm{cm}^2/MW$ at $1.064{\mu}m$. When static electric field of 3.45 KV fmm is applied, the anisotropy ratio of n, is measured to be 1.34 and the molecular orientational order parameters $

_2 and

_4$ are found to be 0.092 and -0.128, respectively. ively.

• PNF and Movement
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• v.11 no.2
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• pp.127-134
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• 2013

Purpose : The purpose of this study of normal elderly and stroke patients by comparing the dominant side and recessive side was to evaluate the differents between each Methods : Thirty-two elderly participated in this study. They were classified two groups: stroke patients group and the normal elderly group. Outcome measures were: general characteristics and BMD. General characteristics included age, height, weight and body mass index. BMD was represented in the osteoporosis index, T-score and Z-score. The measurements of bone mineral density were evaluated on the calcaneus region of the dominant and recessive side, using OsteoPro. The data analyzed using SPSS 17.0 software and the Paired-sample T-test and the Independent-sample T-test Results : OI, T-score, Z-score showed no significant differences between dominant side and recessive side in normal elderly group. But stroke patients group showed OI, T-score, Z-score significant differences between paretic side and nonparetic side. Change score subtracted recessive side from dominant side was significant differences between stroke patients group and normal elderly group. Conclusion : There is positive relationship between physical activity and BMD in stroke patients. Therefore, improved physical activity can have a beneficial effect by reducing osteoporosis in stroke patients, considering a positive relationship between physical activity and BMD.

• Geomechanics and Engineering
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• v.35 no.4
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• pp.367-383
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• 2023

The present paper examines the natural frequency responses of the bi-directional (n_x-n_y, n_y-n_z and n_z-n_x) and multidirectional (n_x-n_y-n_z) functionally graded (FG) plate and curved structures with and without porosity. The even and uneven kind of porosity pattern are considered to observe the influence of porosity type and porosity index. The numerical findings have been obtained using a higher order shear deformation theory (HSDT) based isometric finite element (FE) approach generated in a MATLAB platform. According to the convergence and validation investigation, the proposed HSDT based FE model is adequate to predict free vibrational responses of multidirectional porous FG plates and curved structures. Further a parametric analysis is carried out by taking various design parameters into account. The free vibrational behavior of bidirectional (2D) and multidirectional (3D) perfect-imperfect FGM structure is examined against various power law index, support conditions, aspect, and thickness ratio, and for the curvature of curved structures. The results indicate that the maximum non-dimensional fundamental frequency (NFF) value is observed in perfect FGM plates and curved structures compared to porous FGM plates and curved structures and it is maximum for FGM plates and curved structures with uneven kind of porosity than even porosity.

• Korean Journal of Optics and Photonics
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• v.9 no.5
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• pp.342-347
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• 1998

We present a theoretical analysis of Gaussian beam propagation in nonlinear Kerr media by using aberration-free approximation and Huygens-Fresnel diffraction integral and obtain a simple analytic formular for Z-scan characteristics. Z-scan experiments are carried out on amorphous $As_2S_3$ thin film and compared with the theory developed, showing good agreement. The sign and the value of ${\gamma}$ have been measured at 633 nm to be $+8.65{\times}10^{-6}\textrm{cm}^2/W$. We also measured the far-field intensity profiles, which confirm again self-focusing effect.

• The Journal of the Korean dental association
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• v.18 no.5 s.134
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• pp.355-359
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• 1980

64 dental students who had brushed their teeth with scrubbing method, using 'W' dentifirice for a long lime, were made to practise either scrubbing or Bass method. using one of the 'W','X','Y','Z' toothpaste instead of only 'W' paste for recent 3 weeks. Dental plaque on the teeth of every students were carefully examined compared the results. The simplified oral hygiene index was applied for this purpose and following conclusions were achieved. 1) The Scrubbing method of tooth-paste 'X', Bass method of tooth-paste 'X', and the Bass method of tooth-paste 'Z' had an obvious effect to inhibition of accumulation of plaque. 2) In the tooth brushing method, the scrubbing and Bass are both effective in reducing the plaque accumulation 3) The tooth paste 'X' has the most effectiveness in reducing the plaque accumulation among four tooth pastes 4) The difference in the value of plaque index between the tooth pastes, 'W' and 'X' was only significant statisticallay

• International Journal of Industrial Entomology and Biomaterials
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• v.32 no.2
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• pp.60-68
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• 2016

Pheromone orientation in moths is an exemplar of olfactory sensitivity. To avoid cross mating, the responses of males to pheromone blends must be high specificity and temporal resolution. We tested the effects of olfactory self- and cross-adaptation of pheromone compounds and mixtures in Spodoptera litura moths by electroantennogram (EAG) recordings. The challenge of S. litura antennae to a pulse train of its own pheromone blends of Z9,E11-14:OAc and Z9,E12-14:OAc with 200 ms on/off and 1 s on/off indicated that the repetitive stimulation by 200 ms on/off with high dosages resulted in greater adaptation than that by 1 s on/off with low dosages and the adaptation index of Z9,E11-14:OAc in all treatments is significantly larger than that of Z9,E12-14:OAc, suggesting that high dosages with more frequent stimulation prefer to induce sensory adaptations and a different odor coding exist between the two components in the antennal periphery in this moth. The cross-adaptation EAG test among the two pheromone compounds and Z7-12:OAc and Z9-14:OH from congeneric species of S. litura showed that each of these compounds adapted the antenna more to that specific compound. The significantly higher adaptation to Z7-12:OAc and Z9-14:OH than to the pheromone components of S. litura induced by themselves suggested that both of them are coded by specific odor receptor neurons which are different from those tuned to the pheromone components of S. litura . Thus, we proposed that Z7-12:OAc and Z9-14:OH may play an important role in avoidance of heterospecific mating between S. litura and its sympatric moth species.

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.149-149
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• 2016

Pheromone orientation in moths is an exemplar of olfactory sensitivity. To avoid cross mating, the responses of males to pheromone blends must be high specificity and temporal resolution. We tested the effects of olfactory self-and cross-adaptation of pheromone compounds and mixtures in Spodoptera litura moths by electroantennogram (EAG) recordings. The challenge of S. litura antennae to a pulse train of its own pheromone blends of Z9,E11-14:OAc and Z9,E12-14:OAc with 200 ms on/off and 1 s on/off indicated that the repetitive stimulation by 200 ms on/off with high dosages resulted in greater adaptation than that by 1 s on/off with low dosages and the adaptation index of Z9,E11-14:OAc in all treatments is significantly larger than that of Z9,E12-14:OAc, suggesting that high dosages with more frequent stimulation prefer to induce sensory adaptations and a different odor coding exist between the two components in the antennal periphery in this moth. The cross-adaptation EAG test among the two pheromone compounds and Z7-12:OAc and Z9-14:OH from congeneric species of S. litura showed that each of these compounds adapted the antenna more to that specific compound. The significantly higher adaptation to Z7-12:OAc and Z9-14:OH than to the pheromone components of S. litura induced by themselves suggested that both of them are coded by specific odor receptor neurons which are different from those tuned to the pheromone components of S. litura. Thus, we proposed that Z7-12:OAc and Z9-14:OH may play an important role in avoidance of heterospecific mating between S. litura and its sympatric moth species.

• Journal of the Korean Mathematical Society
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• v.54 no.5
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• pp.1411-1440
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• 2017

We study free actions of finite groups on 3-dimensional nil-manifolds with the first homology ${\mathbb{Z}}^2{\oplus}{\mathbb{Z}}_p$. By the works of Bieberbach and Waldhausen, this classification problem is reduced to classifying all normal nilpotent subgroups of almost Bieberbach groups of finite index, up to affine conjugacy.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.54-59
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• 1999

This study was to quantify fiber distributions in thickness direction of kenaf handsheets as a fiber distribution index (FDI) and to analyze the relationship between FDI and the handsheet properties. The images of fiber distribution in z-direction were obtained by Confocal Laser Scanning Microscope (CLSM) and analyzed by image analysis technique. The proposed FDI had a good correlation with high R2 vlaues with various properties of paper, such as apparent density, scattering coefficient , burst index, tear index, tensile index, and folding endurance. The proposed FDI was shown as a good index to quantify paper properties.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.165-170
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• 2011

Recently natural disasters such as the frequency and intensity of drought have been increasing as a result of climate change. This study suggests a drought index, WADI (Water Availability Drought Index), that considers water availability using 6 components (water intake, groundwater level, agricultural reservoir water level, dam inflow, streamflow, and precipitation) using the Z score and data monitoring on a nationwide level. SPI (Standardized Precipitation Index) was applied in coastal area. For the severe droughts of 2001 spring and 2008 autumn, the index was evaluated by comparison with reported damage areas. suggested to combine The spatial concordance rate of WADI in 2001 and 2008 for estimation of the degree of drought severity was 50 % and 24 % compared to the actual recorded data respectively.