• Journal of the Korean Professional Engineers Association
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• v.17 no.3
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• pp.6-21
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• 1984

A rock slide in amount of 100 tons in weight happened at 7: 10 a.m., 4th October 1982, on the southwestern ridge of Mt. Seunghag, Busan City. The original rock mass of the rock slide is located 850m west from the Dangri Crushed Stone Quarry. The geology of the area consists of agglomerate, andesite, andesitic tuff, and shale hornfels of the Cretaceous Yucheon Group. The rock blocks were first shifted along the steep joint plane on an andesite outcrop at the site and then to the eastern foot of the mountain slope where some private houses are placed. The mountain slope is covered with thick superficial soil. A slided monolithic-block with 83 tons in weight from the rock slide met with an accident of striking against a house with a tremendous force, to which much damage was done as much as its half was destroyed. The rock-slided block pierced the board-floored room only posited at the center and by the bedroom of the house making a pass like a bullet hole, and hence cut a big pine tree with 24 centimeters in diameter at a distance of 26 meters down the house. However nobody was killed or injured in the stricken house, though seven family members were stayed therein at the very time of accident. They really met a rare opportunity in an unhappy disaster. Measurements of the rock slide were made in the course of the field survey. The monolithic mass was transported by way of saltation, rolling, and sliding to a distance of 300 meters down along the slope dipping 30$^{\circ}$ east. It took about 16 seconds front tile outcrop to the terminal. The acceleration value of the monolithic rock slide is 2.35m/sec$^2$.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.2
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• pp.349-354
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• 2002

In order to decolorize the reactive dye wastewater, we investigated the dye-adsorption ability of chitin, which was natural polymer obtained from shrimp shell. Chitin particle(less than 250 ${\mu}{\textrm}{m}$n) was prepared from shrimp shells in the processes of decalcification in aqueous hydrochloric acid solution and deproteination in aqueous sodium hydroxide solution. The particle size of chitin was controlled to less than 250 ${\mu}{\textrm}{m}$. Three tripes of the reactive dyes-C.I. Reactive Red 120, C.I. Reactive red 241 and C.I. Reactive Black 5-were used. Dye adsorption ability of chitin was investigated by dipping the particle in the dyebaths of concentration of 0.0l%, 0.03% and 0.05% for various periods of time(1,3,5, 10,20,40,80,160minutes). The influence of addition of salt(Na$_2$SO$_4$) and alkali to the dyebaths on dye-absorption was also investigated. We obtained the following results fur the dye-absolution ability of chitin in the dyebaths of three types of reactive dyes. 1) The amount of dye uptake by chitin was increased by addition of salt to the dyebaths. 2) As the concentration of alkali became higher than 3g/I, the amount of dye uptake by chitin was increased. Chitin showed good dye-adsorption ability, when the alkali concentration was high. 3) Chitin showed equal dye uptake in the three types of dyebaths when the dye concentration was 0.0l%. Over 90% of dyestuffs was adsorbed from the dyebaths in ten minutes. When the dye concentration was higher, better adsorption ability was showed in a dye bath of Reactive black 5 than in the others. When the dye concentration was 0.03%, 90% of Reactive red 120 and Reactive red 241 was adsorbed in 40 minutes and the same of Reactive black 5 in 10 minutes. When the dye concentration was 0.05%, 9()% of Reactive red 120 was adsorbed in 80 minutes, and Reactive black 5 in to minutes.

• 보존과학연구
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• s.30
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• pp.149-155
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• 2009

Annals of the Joseon Dynasty were composed of 1,229 volumes, and the 475 copies of total annals were wax-treated. Compared to non-wax treated copies, waxed volume of annals were seriously damaged such as crack, stick, discoloration to brown or black, and partially degradation. It is believed that the purpose of wax treatment for some volumes in the annals of the Joseon Dynasty is to prevent paper to deteriorate and to keep for the long time. But, beeswax could be deteriorated itself more rapidly. As a result, the waxed volume was much more damaged than non-waxed volume. Therefore, the investigation of decomposition and deterioration mechanism of beeswax-treated paper which might be used in waxed volume of the annals of the Joseon Dynasty must be done in order to prevent further decomposition and to restore the degraded wax-treated copies of the annals. For basis data of this purpose, physical properties of beeswax-treated paper be analyzed by coating methods. In result, sample products was manufactured reproducibility in lab scale. Specially, beeswax-treated method improved a orientation of papers. And the brushing method was stronger than the dipping method.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.194-204
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• 2014

Purpose: The aim of this study was to develop long-term storage technology for Chinese cabbage in order to extend the period of availability of freshly harvested products. The scope of the paper deals with the use of a cooler with a remote monitoring and control interface in conjunction with use of packaging film. Methods: A cooler with a real time monitoring system was designed as a low-temperature storage facility to control temperature and relative humidity (RH). The effects of storage in high-density polyethylene (HDPE) plastic boxes, 3% chitosan dipping solution, polypropylene film (PEF) with perforations, and mesh packaging bags on physiological responses were investigated. The optimal storage temperature and humidity for 120 days were below $0.5^{\circ}C$ and 90%, respectively. Physiological and biochemical features of cabbage quality were also analyzed: weight loss, texture, and sugar salinity, chlorophyll, reducing sugar, and vitamin C contents. Results: The cooler with a remote monitoring and control interface could be operated by an HMI program. A $0.5^{\circ}C$ temperature and 90% humidity could be remotely controlled within the cooler for 120 days. Postharvest freshness of Chinese cabbages could be maintained up to 120 days depending on the packaging method and operation of the remote monitoring system. In particular, wrapping the cabbages in PEF with perforations resulted in a less than a 5% deterioration in quality. This study provides evidence for efficient performance of plastic films in minimizing post-harvest deterioration and maintaining overall quality of cabbages stored under precise low-temperature conditions with remote monitoring and a control interface. Conclusions: Packaging with a modified plastic film and storage in a precisely controlled cooler with a remote monitoring and control interface could slow down the physiological factors that cause adverse quality changes and thereby increase the shelf life of Chinese cabbage.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.461-466
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• 1999

The humidity sensor containing ammonium salt was prepared from the copolymer of 2-methacryloxyethyl dimethyl 2-hydroxyethyl ammonium bromide (MDHAB)/MMA/DAEMA = 6/3/1. The humid membrane was fabricated on the gold/alumina electrode by dipping. The impedances were $298k{\Omega},\;11k{\Omega}$, and $2.3k{\Omega}$ at 40%RH, 70%RH and 90%RH, respectively, at $5^{\circ}C$ and the humidity-sensitive characteristics were suitable for low temperature humidity sensor. The temperature-dependent coefficient between $5^{\circ}C$ and $20^{\circ}C$ was found to be $-0.80%RH/^{\circ}C$ and the hysteresis falled in the ${\pm}2%RH$ range. The response time was found to be 38 sec for the relative humidity ranging from 34%RH to 88%RH at $20^{\circ}C$. The reliabilities such as temperature cycle, humidity cycle, high temperature and humidity resistance, electrical load stability, stability of long-term storage and water durability were measured and evaluated for the application as a humidity sensor.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.3
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• pp.476-483
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• 2010

The present study was performed to investigate the putative anxiolytic-like effects of the aqueous extract of the roots of Scrophularia buergeriana (SB-W) using elevated plus-maze (EPM) and hole-board apparatus in mice. SB-W was orally administered at doses of 50, 100, 200 or 400 mg/kg to ICR mice, 1 h before the behavioral evaluation. Control group were administered with an equal volume of saline, and positive control group with buspirone (2 mg/kg, i.p.). The administration of SB-W significantly increased the percentage of time spent in open arms and entries into the open arms of the EPM compared with saline-treated control group (P < 0.05). Futhermore, those anxiolytic-like activities of SB-W were antagonized by flumazenil (a $GABA_A$ antagonist, 10 mg/kg), but not by WAY-100635 (a 5-$HT_{1A}$ antagonist, 0.3 mg/kg). Moreover, there were no changes in the locomotor activity and myorelaxant effects in any group compared with saline-treated control group. In the hole-board test, the administration of SB-W (200 and 400 mg/kg) significantly increased the number of head-dipping compared with saline-treated control group (P < 0.05). Therefore, these findings suggest that Scrophularia buergeriana promotes the anxiolytic-like activity mediated by GABAergic nervous system in mice.

• The Journal of Engineering Geology
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• v.11 no.3
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• pp.255-267
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• 2001

A comparison study is performed to understand the coupling behavior of the thermal, hydraulic, and mechanical interactions in the vicinity of an underground radwaste repository, assumed to be located at a depth of 500 m, within a granitic rock mass with a 58$^{\circ}$ dipping fault passing through the roof-wall intersection of the repository cavern. The two dimensional universal distinct element code, UDEC is used for the analysis. The model includes a granitic rock meas, a canister with PWR spent fuels surrounded by the compacted bentonite inside a deposition hole, and the mixed bentonite backfilled in the rest of the space within a repository cavern. The coupling behavior of hydromechanical, thermomechanical, and thermohydromechanical interaction has been studied and compared. The effect of the time-dependent decaying heat, from the radioactive materials in PWR spent fuels, on the repository and its surroundings has been studied. A steady state flow algorithm is used for the hydraulic analysis.

• Applied Microscopy
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• v.22 no.2
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• pp.118-126
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• 1992

The pathway and time course of fucose-containing glycoprotein synthesis and intracellular translocation in osteoclasts of the mice maxillary alveolar bone were investigated by electron microscopic radioautography. Male Balb-C mice weighing 17gm were anesthetized with Nembutal and injected via the external jugular vein with 2.5 mCi of $L-[6-^{3}H]-fucose$ (specific activity 16.8 mCi/mmol) in 0.1 ml of sterile saline solution. At 5, 10, 20, 35 minutes and 8 hours after administration of the $^{3}H-fucose$, animals were killed by intracardiac perfusion of 30ml of 2% glutaraldehyde in a modified Tyroid solution, pH 7.4. The maxillae were then removed and further fixed in Karnovsky fixative for an additional 3-4 hours. After rinsing in 0.1M cacodylate buffer for 10 minutes, the maxillae were demineralized for 2 weeks at $4^{\circ}C$ in ethylene diamine tetra acetate containing 2% glutaraldehyde. The first interdental areas were mesiodistally sectioned into slices of 1mm thickness and postfixed in osmium tetroxide. Tissues were then dehydrated and embedded in Poly Bed. To prepare electron microscopic radioautography, the dipping method of Kopriwa (1973) was employed. Thin sections were coated with a crystalline monolayer of ILford $L_4$ photographic emulsion. After exposure for 4 months at $4^{\circ}C$, the sections were developed Kodak Microdol-X and Phenidon (for compact grains), fixed in 30% sodium thiosulfate, stained with uranyl acetate and lead citrate and examined in the electron microscope (JEOL 1200 EX). At 5, 10 and 20 minutes after injection, $^{3}H-fucose$ was concentrated in Golgi cisternae of the osteoblasts. By 35 minutes the labels were observed over small vesicles in the suprannclear area of osteoclasts. At 8 hours, numerous silver grains were located on the ruffled border and cell membrane of osteoclasts. These results indicate that fucose molecules are added in the Golgi apparatus and small vesicles appear to be responsible for translocation of the glycoproteins to the marginal portion of osteoblasts. The glycoproteins are distributed on the osteoclast cell surface and especially over the ruffled border.

• Journal of Sensor Science and Technology
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• v.27 no.1
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• pp.55-58
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• 2018

Low-cost and large-scale fabrication method of nanohole array, which comprises nanoscale voids separated by a few tens to a few hundreds of nanometers, has opened up new possibilities in biomolecular sensing as well as novel frontier optical devices. One of the key aspects of the nanohole array research is how to control the hole size following each specific needs of the hole structure. Here, we report the extensive study on the fine control of the hole size within the range of 500-2500 nm via surface-catalyzed chemical deposition. The initial hole structures were prepared via conventional photo-lithography, and the hole size was decreased to a designed value through the surface-catalyzed chemical reduction of the gold ion on the predefined hole surfaces, by simple dipping of the hole array device into the aqueous solution of gold chloride and hydroxylamine. The final hole size was controlled by adjusting reaction time, and the optimal experimental condition was obtained by doing a series of characterization experiments. The characterization of size-controlled hole array was systematically examined on the image results of optical microscopy, field emission scanning electron microscopy(FESEM), atomic-force microscopy(AFM), and total internal reflection microscopy.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.554-560
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• 1998

Vinylbenzyl triphenyl phosphonium chloride(VTPC)/styrenes=3.7 copolymer was prepared for the moisture-absorptive polyelectrolyte dew sensor containing phosphonium salts. The humid membrane was fabricated on the gold/alumina electrode by dipping. The impedances were $11M{\Omega}$, $980k{\Omega}$, $50k{\Omega}$, and $11k{\Omega}$ at 70%RH, 80%RH, 90%RH and 95%RH, respectively, at $25^{\circ}C$ and the humidity-sensitive charactristic was suitable for the dew sensor. The temperature-dependent coefficient between $15^{\circ}C$ and $35^{\circ}C$ was found to be $-0.25%RH/^{\circ}C$ and the hysteresis falled in the ${\pm}2%RH$ range. The response time was found to be 45 sec for the relative humidity ranging from 70%RH to 98%RH at $25^{\circ}C$. The reliabilities such as temperature cycle, humidity cycle, high temperature and humidity resistance, electrical load stability, stability of long-term storage and water durability were measured and evaluated for the application as a dew sensor.