• International Journal of High-Rise Buildings
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• v.1 no.4
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• pp.311-332
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• 2012

Earthquake response of mid-rise to high-rise buildings provided with friction dampers is investigated. The steel buildings are modelled as shear-type structures and the investigation involved modelling of the structures of varying heights ranging from five storeys to twenty storeys, in steps of five storeys, subjected to real earthquake ground motions. Three basic types of structures considered in the study are: moment resisting frame (MRF), braced frame (BF), and friction damper frame (FDF). Mathematical modelling of the friction dampers involved simulation of the two distinct phases namely, the stick phase and the slip phase. Dynamic time history analyses are carried out to study the variation of the top floor acceleration, top floor displacement, storey shear, and base-shear. Further, energy plots are obtained to investigate the energy dissipation by the friction dampers. It is seen that substantial earthquake response reduction is achieved with the provision of the friction dampers in the mid-rise and high-rise buildings. The provision of the friction dampers always reduces the base-shear. It is also seen from the fast Fourier transform (FFT) of the top floor acceleration that there is substantial reduction in the peak response; however, the higher frequency content in the response has increased. For the structures considered, the top floor displacements are lesser in the FDF than in the MRF; however, the top floor displacements are marginally larger in the FDF than in the BF.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.181-188
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• 2020

This study was conducted to identify the optimal conditions for seedling growth in Veronica rotunda var. subintegra (Nakai) T.Yamaz. which a endemic plant and can be development as ornamental plants. We sowed V. rotunda var. subintegra (Nakai) T.Yamaz. seeds, and exposed the seedling was different treatment conditions. We varied soil type and fertilizer concentration, shading ratio, additional fertilizer concentration, pretreatment light exposure and collection time of seeds. We found that seedling growth was good in horticultural substrate (with no additional fertilizer), but mixed soils supplemented with fertilizer inhibited growth, regardless of the fertilizer concentration. In the 55% shading treatment, seedling growth was greater than in the non-shading treatment. High concentration addition of fertilizer (Hyponex) promoted plant growth, in terms of both plant length and fresh weight. Exposure of seeds to a red light-source prior to germination had a greater effect on seedling growth than exposure to other light sources. Seedlings exhibited better growth when grown from seed collected in 2018, rather than 2017.

• Interaction and multiscale mechanics
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• v.3 no.1
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• pp.55-79
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• 2010

The effect of soil-structure interaction on a single-storey, two-bay space frame resting on a pile group embedded in the cohesive soil (clay) with flexible cap is examined in this paper. For this purpose, a more rational approach is resorted to using the finite element analysis with realistic assumptions. Initially, a 3-D FEA is carried out independently for the frame on the premise of fixed column bases in which members of the superstructure are discretized using the 20-node isoparametric continuum elements. Later, a model is worked out separately for the pile foundation, by using the beam elements, plate elements and spring elements to model the pile, pile cap and soil, respectively. The stiffness obtained for the foundation is used in the interaction analysis of the frame to quantify the effect of soil-structure interaction on the response of the superstructure. In the parametric study using the substructure approach (uncoupled analysis), the effects of pile spacing, pile configuration, and pile diameter of the pile group on the response of superstructure are evaluated. The responses of the superstructure considered include the displacement at top of the frame and moments in the columns. The effect of soil-structure interaction is found to be quite significant for the type of foundation considered in the study. Fair agreement is observed between the results obtained herein using the simplified models for the pile foundation and those existing in the literature based on a complete three dimensional analysis of the building frame - pile foundation - soil system.

• Journal of Magnetics
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• v.16 no.3
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• pp.211-215
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• 2011

The dynamic magnetostriction characteristics of an Fe-based nanocrystalline FeCuNbSiB alloy are investigated as a function of the dc bias magnetic field. The experimental results show that the piezomagnetic coefficient of FeCuNbSiB is about 2.1 times higher than that of Terfenol-D at the low dc magnetic bias $H_{dc}$ = 46 Oe. Moreover, FeCuNbSiB has a large resonant dynamic strain coefficient at quite low Hdc due to a high mechanical quality factor, which is 3-5 times greater than that of Terfenol-D at the same low $H_{dc}$. Based on such magnetostriction characteristics, we fabricate a new type of transducer with FeCuNbSiB/PZT-8/FeCuNbSiB. Its maximum resonant magnetoelectric voltage coefficient achieves ~10 V/Oe. The ME output power reaches 331.8 ${\mu}W$ at an optimum load resistance of 7 $k{\Omega}$ under 0.4 Oe ac magnetic field, which is 50 times higher than that of the previous ultrasonic-horn-substrate composite transducer and it decreases the size by nearly 86%. The performance indicate that the FeCuNbSiB/PZT-8/FeCuNbSiB transducer is promising for application in highly efficient magnetoelectric energy conversion.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.3
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• pp.225-231
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• 2013

Oil in water nanoemulsion of astaxanthin was prepared by high pressure homogenization. The emulsifying conditions including emulsifier type, concentration and astaxanthin concentration were optimized. Stability of nanoemulsion was measured using zetasizer, freeze-fracture scanning electron microscope (FF-SEM), particle analyzer and colorimeter. The mean diameter of the dispersed particles containing astaxanthin ranged from 160 to 190 nm. Size distribution was unimodal and extended from 40 to 200 nm. The nanoemulsion prepared by glyceryl citrate/lactate/linoleate/oleate had smaller particle size and narrow size distribution. Stable incorporation of astaxanthin in nanoemulsion was performed and checked using high performance liquid chromatography (HPLC), freeze-fracture scanning electron microscope (FF-SEM). Physical stability of nanoemulsion was not significantly changed during storage at both light and thermal condition for a month with zeta potential value of -41 mV meaning stable colloid.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.11-13
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• 2000

Cancer is a general term subjected to a series of malignant tumor diseases which may affect many different parts of the human body. These cancer diseases are characterized by a rapid and uncontrolled formation of abnormal cells in the body. Cancer chemotherapeutic agents can often provide the prolongation of life and occasionally cures. To date many kinds of compounds have been obtained from plants kingdom as anti-neoplastic and anti-cancerous agents. However, there is no special type of compounds for cancer therapy. In our laboratory, anti-tumor and cytotoxic screenings on higher plants collected in Japan, China, Korea, Southeast Asia and South America have been done by using Sarcoma 180 ascites in mice, P388 lymphocytic leukemia in mice, Chinese hamster lung V-79 cells, P388 cells and nasopharynx carcinoma (KB) cells. The family, Simaroubaceae consists of about 20 genera and 120 species, mainly shrubs and trees, distributed in tropical and subtropical country. Simaroubaceae IS classified as RUTALES, together with Rutaceae, Burseraceae, Meliaceae, Malpighiaceae and Polygalaceae. The members differ from the Rutaceae in not containing oil glands. Bitter principles are a characteristic of the family, Simaroubaceae. The genera include Quassia (Simarouba) (40 spp.), Picrasma (Aeschrion) (6 spp.), Brucea (10 spp.), Soulamea (10 spp.), Ailanthus (10 spp.) and Perriera (1 spp.) etc.. Surinam quassia derived from Quassia amara growing in Guianas, north Brazil and Venezuela is used in traditional medicines for stomachic, anti-amoebic, anti-malarial and anti-anaemic properties. Also, various parts of a number of plants of the family Simaroubaceae have been used in traditional medicine for the treatment of a variety of diseases including cancer, amoebic, dysentery and malaria. Then, the research has established that it is the quassinoid content of these plants that is responsible for above activities. In this meeting, I will present on anti-tumor and anti-malarial activities and their active principles of Simaroubaceae plants, Eurycoma longifolia, Ailanthus vilmoriniana, Simaba cedron and Brucea mollis which have been studied in our laboratory.

• YAKHAK HOEJI
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• v.37 no.6
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• pp.605-614
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• 1993

To investigate the endothelial dependence of angiotensin II(A II)-induced responses in the systemic and pulmonary arterial system of acute renal hypertensive rats of 2-kidney, 1-ligation type (RHRs), A II-induced vasocontractile and pressor effects were evaluated in isolated arteries and in vivo, respectively. A II dose-dependently contracted intact thoracic aorta and pulmonary artery (E$_{max}$:40% at 10$^{-7}$M and 80% at 3$\times$10 $^{-8}$M, respectively) from normotensive rats(NRs), which was significantly increased by removal of endothelial cells or pretreatment with EDRF inhibitors. In NRs, A II increased mean systemic and pulmonary arterial pressure(33 and 5.6mmHg at 0.1 $\mu\textrm{g}$/kg, respectively), the effect being significantly increased (P<0.01) by L-NAME(30mg/kg, i.v.). However, A II-induced contraction of intact thoracic aorta and pulmonary artery(E$_{max}$: 33% at 10$^{-7}$M and 93% at 3$\times$10$^{-8}$M, respectively) from RHRs were not changed after endothelial function was disrupted as above; similarly, pressor effects of A II on the systemic and pulmonary arterial pressure in RHRs did not altered by L-NAME. A II tachyphylactic responses for intact thoracic aorta from NRs and RHRs(65 and 87% at 10$^{-8}$M, respectively) were greater than those for pulmonary artery(19 and 19% at 10$^{-8}$M, respectively). Distruption of endothelial function significantly (P<0.01) depressed A II tachyphylaxis for thoracic aorta, but not for pulmonary artery. These results suggest that vascular reactivity to A II is not altered in RHRs, and it is greater for pulmonary arterial system than for systemic arterial system. A II reactivity is EDRF-dependent in both arterial systems of NRs, but EDRF-independent for RHRs. Finally, EDRF is one of the major factors underlying A II tachyphylaxis for thoracic aorta, but not for pulmonary artery.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.33-41
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• 1999

Whereas as selective inhibitor of monoamine oxidase type B, ${\ell}-deprenyl$ (selegiline), is now widely used in the treatment of Parkinson's disease, the precise action mechanism of the drug remains elusive. In this study, to investigate protective effect of ${\ell}-deprenyl$ against the dopamine depletion induced by 6-hydroxydopamine (6-OHDA), the changes in tissue contents of dopamine, serotonine (5-HT) and their metabolites by ${\ell}-deprenyl$ were examined in intact and 6-OHDA-lesioned rat brain. In intact rats, a single intraperitoneal (i.p.) administration of ${\ell}-deprenyl$ showed a no change in striatal dopamine and its metabolites at low concentrations (0.25 and 1 mg/kg), but significantly inhibited dopamine metabolism at a higher concentration (10 mg/kg). The repeated administration of ${\ell}-deprenyl$ (0.25 and 1 mg/kg, i.p., for 21 consecutive days) reduced the contents of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA) in dose-dependent manners without changes in dopamine content. Bilateral intracerebroventricular (i.c.v) infusion of 6-OHDA ($100{\;}\mu\textrm{g}/10{\;}{\mu}{\ell}/hemisphere$) depleted dopamine in striatum and septum by 81% and 90% respectively. When rats were pretreated with ${\ell}-deprenyl$ before 6-OHDA administration, the striatal and septal dopamine levels were significantly increased by about 3.0-fold and 3.4-fold, respectively, compared to the untreated 6-OHDA-lesioned rat. Pretreatment of ${\ell}-deprenyl$ also significantly enhanced the dopmaine metabolites, DOPAC, HVA and 3-methoxytyramine, in the striatum, and DOPAC in the septum. These results indicate that a ${\ell}-deprenyl$ pretreatment prevents 6-OHDA-induced depletion of striatal dopamine and its metabolites.

• Journal of Magnetics
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• v.8 no.4
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• pp.138-141
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• 2003

$Ni_{0.65}Zn_{0.35}Fe_2O_4$thin films were prepared by using a sol-gel method. Their crystallographic, dielectric and magnetic properties were investigated as a function of Cu contents by means of an X-ray diffractometer (XRD), X-ray reflectivity, LCZ meter (NF2232), a vibrating sample magnetometer (VSM), and an atomic force microscope (AFM). From typical C-V measurements for $Ni_{0.65}Zn_{0.35}Fe_2O_4$ thin films on p-type silicon substrate, the surface charge density was calculated as 1.4 ${\mu}$C/$m^2$. The dielectric constant evaluated from the capacitance at the accumulation state was 28. The high $H_{c}$ and low $M_{sat}$ at x=0.0 and 0.1 were due to the growth of the ${\alpha}$-$Fe_2O_3$ phase having antiferromagnetic properties. The rapidly decreased $H_{c}$ and increased $M_{sat}$ at x=0.2 and 0.3 can be explained that the ${\alpha}$-$Fe_2O_3$ phases have completely disappeared at x=0.3 and so, non-magnetic defects are minimized. The $M_{sat}$ was slightly decreased and the $H_{c}$ was increased above at x=0.3 because the increase of grain boundary due to smaller grain size acts as defects during magnetization process.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.99.2-99.2
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• 2012

We updated the far-ultraviolet (FUV) spectral images of the entire Vela supernova remnant (SNR) using newly processed FIMS/SPEAR data. In the present study, we compare the newly produced FUV images with the X-ray and $H{\alpha}$ images, and examine how the Vela SNR evolves and interacts with the ambient medium on a global scale. The comparison with X-ray images has revealed a FUV filamentary feature corresponding with the boundary of the northeast-southwest asymmetry of the X-ray shell. The relatively low O IV] ${\lambda}1404$ to O III] ${\lambda}{\lambda}1661$, 1666 ratio estimated on the FUV filament is compatible with the previous proposal that the observed asymmetry of the Vela SNR could be due to the ${\gamma}2$ Velorum stellar wind bubble (SWB). The southwest FUV features surrounding a faint extended X-ray region are characterized as the region where the Vela SNR is interacting slightly stronger with ambient mediums within the dim X-ray southwest section. From a comparison with the $H{\alpha}$ image, we identify a ring-like $H{\alpha}$ feature overlapped with an extended hot X-ray feature of similar size and two local peaks of C IV ${\lambda}{\lambda}1548$, 1551 emission. Their morphologies are consistent with the expected shape when the $H{\alpha}$ ring is in direct contact with the near or far side of the Vela SNR. We suggest that the B3V-type star HD 76161 found at the center of the $H{\alpha}$ ring would be the exciting source of the H II region.