• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.7
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• pp.503-509
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• 2013

In this study, $Cu(In_{1-x},Ga_x)Se_2$ (CIGS) thin films were prepared on the Mo coated soda-lime glass by the DC magnetron sputtering and a subsequent selenization process. For the selenization process, selenization rapid thermal process(RTP) with cracker cell, which was helpful to smaller an atomic of Se, was adopted. To make CIGS layer, they were then annealed with the cracked Se. Based on this selenization method, we made several CIGS thin film and investigated the effects of In deposition time, and selenization time. Through x-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and atomic force microscopy (AFM), it is found that the Mo/In/CuGa structure and the high sputtering power shows the dominant chalcopyrite structure and have a uniform distribution of the grain size. The CIGS films with the In deposition time of 5 min has the best structure due to the smooth surface. And CIGS films with the selenization time of 50 min show good crystalline growth without any voids.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.237.2-237.2
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• 2013

ReRAM cell, also known as conductive bridging RAM (CBRAM), is a resistive switching memory based on non-volatile formation and dissolution of conductive filament in a solid electrolyte [1,2]. Especially, Chalcogenide-based ReRAM have become a promising candidate due to the simple structure, high density and low power operation than other types of ReRAM but the uniformity of switching parameter is undesirable. It is because diffusion of ions from anode to cathode in solid electrolyte layer is random [3]. That is to say, the formation of conductive filament is not go through the same paths in each switching cycle which is one of the major obstacles for performance improvement of ReRAM devices. Therefore, to control of nonuniform conductive filament formation is a key point to achieve a high performance ReRAM. In this paper, we demonstrated the enhanced repeatable bipolar resistive switching memory characteristics by spreading the Ag nanocrystals (Ag NCs) on amorphous GeSe layer compared to the conventional Ag/GeSe/Pt structure without Ag NCs. The Ag NCs and Ag top electrode act as a metal supply source of our devices. Excellent resistive switching memory characteristics were obtained and improvement of voltage distribution was achieved from the Al/Ag NCs/GeSe/Pt structure. At the same time, a stable DC endurance (>100 cycles) and an excellent data retention (>104 sec) properties was found from the Al/Ag NCs/GeSe/ Pt structured ReRAMs.

• The Korea Journal of Herbology
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• v.34 no.1
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• pp.1-11
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• 2019

Objective : An allergy to peanuts is a major cause of fatal food-induced anaphylaxis, with food allergies becoming an increasingly important health research issue. Food allergy as clinical entity has been recongnized for many years, although there is yet no general concord as to the incidence of this symptom.1) Methods : This study was undertaken to verify the effect of seeds of Canavalia gladiata (Jacq.) DC. extract (CGE) on the inhibition of allergic reactions using a cholera toxin and peanut extract-immunized food allergy mouse model. We determine whether the changes in rectal temperature were related to energy consumption owing to heat production in the body. Mast cell distribution and degranulation in the dermis and epidermis were observed with an optical microscope. Subsequently, Ara h1 levels in serum and interleukin (IL)-4, IL-10, and $IFN-{\gamma}$ levels in cultured supernatants of splenocytes were measured. Results : CGE treatment significantly attenuated the secretion of the Ara h1 antibody in serum and splenocytes. Ara h 1 was undetected in the cholera toxin and peanut extract-immunized food allergy mouse model. Improvement in ear tissue inflammation symptoms was the CGE experimental group. In the control group and peanut extract control group, the expression of mast cells was higher, whereas that in the CGE experimental group was significantly lower. Conclusion : CGE causes suppression in a food allergy mouse model via the inhibition of Ara h1 secretion, and might be useful for developing functional health foods.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.90-104
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• 2001

This study is aimed to analyze and to evaluate the revegetation and soil conservation technology in desertification-affected sandy land, resulting from the project of "Studies on the desertification combating and sand industry development". Main native plants for combating desertification : The general characteristics of vegetation distribution in desertified regions are partially concentrated vegetation distribution types including the a) desert plants in low zone of desert or sanddune of depressed basin, b) salt-resistant plants around saline lakes, c) grouped vegetation with Poplar and Chinese Tamarix of freshwater-lakes, saline-lakes and river-banks, d) gobi vegetation of gravel desert and e) grassland and oasis-woods around the alluvial fan of rivers, etc. Generally, Tamarix ehinensis Lour., Haloxylon ammodendron Bunge., Calligonum spp., Populus euphratica Oliver., Elaeagnus angustifolia L., Ulmus pumila L., Salix spp., Hedysarum spp., Caragana spp., Xanthoceras sorbifolia Bunge., Nitraria tangutorum Bobr., Lespedeza bicolor, Alhagi sparsifolia Shap., Capparis spinosa L., Artemisia arenaria DC., etc. are widely distributed in desertified regions. It is necessary for conducting research in the native plants in desertified regions. Analysis of intensive revegetation technology system for combating desertification : In the wind erosion region, the experimental research projects of rational farming systems (regional planning, shelterbelts system, protection system of oasis, establishment of irrigation-channel networks and management technology of enormous farmlands, etc.), rational utilization technology of plant resources (fuelwood, medicinal plants, grazing and grassland management, etc.), utilization technology of water resources (management and planning of watershed, construction of channel and technology of water saving and irrigation, etc.), establishment of sheltetbelts, control of population increase and increased production technology of agricultural forest, fuelwood and feed, etc. are preponderantly being promoted. And in water erosion region, the experimental research projects of development of rational utilization technology of land and vegetation, engineering technology and protection technology of crops, etc. are being promoted in priority. And also, the experimental researches on the methods of utilization of water (irrigation, drainage, washing and rice cultivation, etc.), agricultural methods (reclamation of land, agronomy, fertilization, seeding, crop rotation, mixed-cultivation and soil dressing works, etc.) and biological methods (cultivation of salt-resistant crops and green manure and tree plantation, etc.) for improvement of saline soil and alkaline soil in desertified-lands are actively being promoted. And the international cooperations on the revegetation technology development projects of desertified-lands are sincerely being required.

• Korean Journal of Materials Research
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• v.20 no.10
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• pp.501-507
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• 2010

Changes in surface morphology and roughness of dc sputtered ZnO:Al/Ag back reflectors by varying the deposition temperature and their influence on the performance of flexible silicon thin film solar cells were systematically investigated. By increasing the deposition temperature from $25^{\circ}C$ to $500^{\circ}C$, the grain size of Ag thin films increased from 100 nm to 1000 nm and the grain size distribution became irregular, which resulted in an increment of surface roughness from 6.6 nm to 46.6 nm. Even after the 100 nm thick ZnO:Al film deposition, the surface morphology and roughness of the ZnO:Al/Ag double structured back reflectors were the same as those of the Ag layers, meaning that the ZnO:Al films were deposited conformally on the Ag films without unnecessary changes in the surfacefeatures. The diffused reflectance of the back reflectors improved significantly with the increasing grain size and surface roughness of the Ag films, and in particular, an enhanced diffused reflectance in the long wavelength over 800 nm was observed in the Ag back reflectors deposited at $500^{\circ}C$, which had an irregular grain size distribution of 200-1000 nm and large surface roughness. The improved light scattering properties on the rough ZnO:Al/Ag back reflector surfaces led to an increase of light trapping in the solar cells, and this resulted in a noticeable improvement in the $J_{sc}$ values from 9.94 mA/$cm^2$ for the flat Ag back reflector at $25^{\circ}C$ to 13.36 mA/$cm^2$ for the rough one at $500^{\circ}C$. A conversion efficiency of 7.60% ($V_{oc}$ = 0.93, $J_{sc}$ = 13.36 mA/$cm^2$, FF = 61%) was achieved in the flexible silicon thin film solar cells at this moment.

• Korean journal of applied entomology
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• v.15 no.2 s.27
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• pp.95-100
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• 1976

A distribution status of host plants for fruit-piercing moths was surveyed in Kocksung fruit growing area of Chonnam province during June to October, 1975. The results were summarized as follows; Main host plants of fruit·piercing larvae Smilax china L., Allizzia zulibrissim Dura, Cocculus trilobus Dc., Thalictrum aquilegifolium L., and Pterocarya rhoifolia Sieb & Zucc. Pterocarya rhoifolia Sieb & Zucc. were found to be distributed at mountain regions over 500m above sea level, while the other host plants were found to be distributed with in loom to 300m above sea level The moths was found from June 25th to Oct. 4th. Maximum emergence of the moths on plum an8 peach were about July 18th and on the grapes tree about August 31th. The moths collected from June 25th to Oct.4th were 17 spcies. Dermaleipa zuno Dalman $(35.7\%)$, Oraesia emaginata Fabriciul$(17.7\%)$, Oraesia excavata Butler $(12.9\%)$, Adrias tyramus amurensis Staduinger$(9.1\%)$, were collected much more than any other species; They accounted for approximately$70\%$ of total moths collected. In regards to the sugar contents of peach and plum, it was observed that the more the sugar concentrated, the more the fruits damaged. but the acid value of fruits had not shown any significant relationship with their attractants.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.7-8
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• 2010

The surface conductive layer (SCL) of chemical vapor deposition (CVD) diamonds has attracting much interest. However, neither photoemission electron microscopic (PEEM) nor micro-spectroscopic (PEEMS) information is available so far. Since SCL retains in an ultra-high vacuum (UHV) condition, PEEM or PEEMS study will give an insight of SCL, which is the subject of the present study. The sample was made on a Ib-type HTHP diamond (001) substrate by non-doping CVD growthin a DC-plasma deposition chamber. The SCL properties of the sample in air were; a few tens K/Sq. in sheet resistance, ${\sim}180\;cm^2/vs$ in Hall mobility, ${\sim}2{\times}10^{12}/cm^2$ in carrier concentration. The root-square-mean surface roughness (Rq) of the sample was ~0.2nm as checked by AFM. A $2{\times}1$ LEED pattern and a sheet resistance of several hundreds K/Sq. in UHV were checked in a UHV chamber with an in-situ resist-meter [1]. The sample was then installed in a commercial PEEM/S apparatus (Omicron FOCUS IS-PEEM) which was composed of electro-static-lens optics together with an electron energy-analyzer. The presence of SCL was regularly monitored by measuring resistance between two electrodes (colloidal graphite) pasted on the two ends of sample surface. Figure 1 shows two PEEM images of a same area of the sample; a) is excited with a Hg-lamp and b) with a Xe-lamp. The maximum photon energy of the Hg-lamp is ~4.9 eV which is smaller that the band gap energy ($E_G=5.5\;eV$) of diamond and the maximum photon energy of the Xe-lamp is ~6.2 eV which is larger than $E_G$. The image that appear with the Hg-lamp can be due to photo-excitation to unoccupied states of the hydrogen-terminated negative electron affinity (NEA) diamond surface [2]. Secondary electron energy distribution of the white background of Figs.1a) and b) indeed shows that the whole surface is NEA except a large black dot on the upper center. However, Figs.1a) and 1b) show several features that are qualitatively different from each other. Some of the differences are the followings: the two main dark lines A and B in Fig.1b) are not at all obvious and the white lines B and C in Fig.1b) appear to be dark lines in Fig.1a). A PEEMS analysis of secondary electron energy distribution showed that all of the features A-D have negative electron affinity with marginal differences among them. These differences can be attributed to differences in the details of energy band bending underneath the surface present in SCL [3].

• The Korea Journal of Herbology
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• v.33 no.5
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• pp.81-88
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• 2018

Objectives : The aim of this study was to investigate the protective effects of an aqueous extract from Taxillus chinensis (DC.) Danser (TCE) in Monosodium iodoacetate (MIA)-induced osteoarthritis (OA) rat model. Methods : Sprague Dawley male rats were divided into the following four groups (n=6 per group): Normal (saline control), MIA (MIA-induced OA with vehicle), TCE (MIA-induced with TCE treatment), and IM (MIA-induced with indomethacin treatment). Rats in which OA was induced by MIA were treated with TCE (200 mg/kg) or indomethacin (1 mg/kg) for 4 weeks. Weight-bearing on the hind legs and body weights were measured weekly. At the end of the experiment (3 weeks after MIA injection), serum aspartate aminotransferase and alanine aminotransferase levels were measured to assess the liver toxicity induced by TCE. Its effects on serum inflammatory cytokine levels and tissue histopathology were also evaluated. Results : TCE restored the hind limb weight-bearing distribution. Serum levels of Interleukin 6 (IL-6), Tumor necrosis factor alpha (TNF-${\alpha}$) and Leukotriene B4 (LTB4) were significantly higher in the MIA group than in the Normal group, but serum IL-6 levels were significantly lower in the TCE group. In the TCE group, the synovial membrane was protected in hematoxylin and eosin and Safranin-O staining, respectively. Conclusions : TCE recovered the hind paw weight bearing distribution, inhibited the production of inflammatory cytokine, and protected synovial tissue and cartilage in the OA rat model. Therefore, TCE appears to be an effective therapeutic agent for treating OA and OA-related symptoms.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.1
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• pp.33-40
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• 2006

The characteristics of the aluminum waste melting and the distribution of the radioactive nuclides have been investigated for the estimation on the volume reduction and the decontamination of the aluminum wastes from the decommissioning of the TRIGA MARK it and III research reactors at the Korea Atomic Energy Research Institute(KAERI). The aluminum wastes were melted with the use of the fluxes such as flux $A:NaCl-KCl-Na_3AlF_6$, flux B:NaCl-NaF-KF, flux $C:CaF_2$, and flux $D:LiF-KCl-BaCl_2$ in the DC graphite arc furnace. For the assessment of the distribution of the radioactive nuclides during the melting of the aluminum, the aluminum materials were contaminated by the surrogate nuclides such as cobalt(Co), cesium(Cs) and strontium(Sr). The fluidity of aluminum melt was increased with the addition of the fluxes, which has slight difference according to the type of fluxes. The formation of the slag during the aluminum melting added the flux type C and D was larger than that with the flux A and B. The rate of the slag formation linearly increased with increasing the flux concentration. The results of the XRD analysis showed that the surrogate nuclide was transferred to the slag, which can be easily separated from the melt and then they combined with aluminum oxide to form a more stable compound. The distribution ratio of cobalt in ingot to that in slag was more than 40% at all types of fluxes. Since vapor pressures of cesium and strontium were higher than those that of the host metals at the melting temperature, their removal efficiency from the ingot phase to the slag and the dust phase was by up to 98%.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.2
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• pp.77-86
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• 2017

A study on the population ecology of gregarious Wisteria habitat was conducted in Beomeosa temple, Busan. The area has been protected since it was designated as No. 176 natural monument in 1966. Such a large habitat of native wisteria (Wisteria floribunda DC.) in Korea is very rare so that it has a very high academic value. However, there are no high-resolution researches on the distribution and ecology of wisteria in the Gregarious Wisteria Habitat of Beomeosa Temple. The study aimed to identify the distribution and characteristics of wisteria populations in the Wisteria habitat. The study identified the distribution of Wisteria, RCC, the climbing direction, the plant and flora in the research area in the Gregarious Wisteria Habitat of Beomeosa Temple in Busan and the surrounding areas based on an on-site research. As a result, the total number of the wisteria populations in the research area was confirmed to be 1,158 and the RCC of wisteria was on average 69.0 mm (${\pm}45.5$) and in maximum 365 mm. In terms of the climbing direction, the number of wisteria that climbs clockwise or counterclockwise was determined to be 40. It was identified that there are 28 taxa of the climbing plant species and the wisteria of the same kind was the most favorable. The populations were found to be dispersed adjacent to the valleys, and were found to be maintained by constant disturbance. 76.6 % of the population was found to be distributed in the valley forest, and the Carpinus tschonoskii-Pseudosasa japonica forest, Pueraria lobata community and Pinus densiflora forest were found to be relatively dispersed. The study proposed to conduct the follow-up researches to preserve the wisteria that is spreading in this research area, the wisteria with the highest RCC and regional habitat through continuous monitoring; and maintain the protection area of No. 176 natural monument; and discussed the management measures and approaches that reflect the habitat.