• Korean Journal of Soil Science and Fertilizer
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• v.49 no.3
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• pp.227-234
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• 2016

The influence of mixing on biogas production and organic material removal performance of solid state anaerobic digestion of dairy manure and sawdust bedding mixtures was evaluated using 22 L volume lab-scale digesters. After 45 days of anaerobic digestion at $37^{\circ}C$, cumulative methane yield of unmixed test unit ($73.1N{\cdot}mL/g-VS$) was almost 1.3 times of that of mixed one ($56.3N{\cdot}mL/g-VS$). The biodegradable volatile solids removal rate of unmixed test unit was 67%, which was almost 28% greater than mixed one. Our results reveal that unmixed condition is better than mixed one in terms of biogas production and organic material reduction.

• Journal of Korean Tunnelling and Underground Space Association
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• v.3 no.3
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• pp.45-56
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• 2001

It is very important to survey in construction for acquiring informations about geological structure which influence the tunnel construction. Usually, TSP(Tunnel Seismic Prediction) one of the seismic survey method in tunnels in Korea has been used for prediction of geological condition ahead of tunnel face, but in this study HSP(Horizontal Seismic Profiling) was used. As a result of field application, we predicted that there exist rock discontinuity such as fault, joints and bedding planes. In addition, RMR value from rock mass evaluation coincided with that from seismic survey for rock condition. We compared with rock classifications and evaluation results for proving.

• Tunnel and Underground Space
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• v.22 no.3
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• pp.205-213
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• 2012

In this study, scaled model tests were performed to investigate the stability of twin tunnels constructed in anisotropic rocks with $30^{\circ}$ inclined bedding planes under the condition of lateral pressure ratio, 2. Five types of test models which had respectively different pillar widths and shapes of tunnel sections were experimented, where both crack initiating pressures and deformation behaviors around tunnels were investigated. The models with shallower pillar width showed shear failure of pillar according to the existing bedding planes and they were cracked under lower pressure than the models with thicker pillar width. In order to find the effect of tunnel sectional shape on stability, the models with four centered arch section, circular section and semi-circular arch section were experimented. As results of the comparison of the crack initiating pressures and the deformation behaviors around tunnels, the semi-circular arched tunnel model was the most unstable whereas the circular tunnel model was the most stable among them. Furthermore, the results of FLAC analysis were qualitatively coincident with the experimental results.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.629-640
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• 2008

South anchorage(AN1, Myodo side) of supension bridge between Myodo and Gwangyang is designed as rock anchorage with 36m anchor length using the resistance of rock mass in Myodo. Checking the overall stability of the anchorage, we considered rock joints, bedding planes, fault zones and condition of rock structure in situ by analysis results for photo-lineaments, aerial photograph interpretation and drill-hole logs are considered. This anchorage consists of an access shaft, adit, and the upper and lower concrete bearing plate to introduce pre-stressing force into rock mass.

• Journal of the Korean housing association
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• v.20 no.1
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• pp.37-44
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• 2009

Sleep has big influence on our life, for example productivity, character formation of babies, mortality and the people who suffered from sleep problem are also diverse. Therefore, indoor environmental supports for good sleep, might be different with the situation and need of respective person. The objectives of this study are: 1) to investigate the current bedroom condition, sleep problem, and life pattern of Korean. 2) to classify Korean into several groups and explain their characteristics relevant to sleep, in order to understand Korean's need for good sleep. The questionnaire was sent out to Seoul and its environs in Jan.$\sim$Feb. 2008, and total of 702 questionnaires were collected. The research on the bedroom condition was conducted around perceived influence of environmental factors, opening and closing of the door, cooling and heating strategy, clo value during sleep, bedding type, lighting, sharing bedroom. People are divided into 6 groups by 8 factors, and 5 groups could be seen that they need some management for good sleep because of their sleep problem.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.507-510
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• 2007

Piston cores retrieved from the western Ulleung Basin, East Sea were analyzed to examine the potential for hydrocarbon generation and to determine the hydrocarbon indicators. 2D multi-channel reflection seismic and Chirp data were also investigated for mapping and characterizing the geophysical hydrocarbon indicators such as BSR (bottom simulating reflector), blank zone, pock-mark etc. High organic carbon contents and sedimentation rates that suggest good condition for hydrocarbon generation. High pressure and low temperature condition, and high residual hydrocarbon concentrations are favor the formation of natural gas hydrate. In the piston cores, cracks generally oriented to bedding may indicate the gas expansion. The seismic data show several BSRs that are associated with natural gas hydrates and underlying free gas. A number of vertical to sub-vertical blank zones were well identified in the seismic sections. They often show the seismic pull-up structures, probably indicating the presence of high velocity hydrates. Numerous pockmarks were also observed in the Chirp profiles. They may indicate the presence of free gas below the hydrate stability zone as well.

• Textile Coloration and Finishing
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• v.17 no.6 s.85
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• pp.42-50
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• 2005

Silk fabrics are widely used as high quality cloth, interior, quilting and bedding materials because of having excellent touch, drape, resilience and low specific gravity characteristics. But, many waste silk materials are produced during the reeling, spinning, weaving, dyeing and finishing processes. From this fact, the recycle of waste silks is interested in studying for the application of industrial textile materials such as filter, oil absorbent and wound protector. Thus, this research has surveyed the decolorizing and carding characteristics in order to recycle the colored waste silk materials. As the results, the carding condition of waste silk fabrics was optimized with different fiber lengths and curding passage. In addition, the fiber failure mechanism from the wasted silk microdamage caused by carding process was investigated. Also it was found that longitudinal and transverse cracks, abrasion and pilling were formed on the surface of wasted silk fibers.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.219-226
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• 2000

The experiments were conducted to investigate the characteristics of the seed germination and the bulb dormancy in Korean-native Allium victorialis L. by the physicochemical treatments. The characteristics of two Allium victorialis seeds was similar in shape, color and threshing but different in other characters. Weight of 1,000 grains in Ullrung-native was 14.8g corresponding to 2.1 times as compared with Odae-native. Seeding immediatly after seed collection of Ullrung-native only germinated and chemicals didn't affect in germination improvement. The germination rate, average days to germination and coefficient of germination of Ullrung-native was 86%, 42 days and 2.05 at the dark condition of control, respectively. The germination rate, average days to germination and coefficient of germination of Odae-native was 70%, 47 days and 1.5 at the dark condition of control and 82%, 47 days, 1.75 at the light condition after 5$^{\circ}C$ prechilling for 30 days, respectively. The bedding days to reduce the physiological dormancy in the bulb of Odae-native assumed to be appropriate up to 45 days after the first prechilling.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.103-110
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• 2003

This study is as for shale that attract recently geotechnical engineer more and more. like sedimentary rocks and metamorpic rocks, shales have many problem with anisotropy for stength and deformation and they have many problems with quick weathering progress and differential weathering of alternate bedding. In foreign countries, many renowned schalors, like Jaeger(1960),McLamore,Gray(1967),Donath(1972),Nova(1980),Hoek&Brown(1980),Ranamurthy(1985), have already studied for a variety of characteristic and announced high level results of their studies. In domestic also, there are many scholars who have announced high level research papers for shale. this study is a part of these stream. and this study not only analyzed strength anisotropy characteristic along with direction of testing(two-direction) by using point-load test(log-log method) but also compared uniaxial strength between the maximum saturated and dried condition. In this study, we also conducted slaking test. these results of slaking test show weathering characteristic of shales. also, we made the most of field data that obtained during slope stability project and we noticed that RQD measured in the field is much differ from drilled core RQD. In order to come close two different value or access to reality, we suggest new RQD method that artificially reduce RQD by separating core with light hand force.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.120-120
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• 2018

Intestinal microbiota is strongly connected to health of host. It has been reported that not only metabolic disease like diabetes and obesity, but psychological diseases are affected by composition of intestinal microbiota. To figure it out the importance of the composition and relationship between disease and microbiota, intensive researches have done with human and experimental animals. But, the composition of the intestinal microbiota could be affected by several factors such as experimental environments, feeding, water, and bedding. As a result, the data from each experimental group might be diverse. It also affects experiments about biological activities of plant materials. In this study, mouse intestinal bacteria were isolated from fresh feces and identified by 16S rRNA gene to use in biological activities of natural medicines. The fecal supernatant was anaerobically incubated at $37^{\circ}C$ for 48 hours. Colonies were picked up separately and incubated again in same condition to increase quantity to analyze and stock. The bacteria strains were listed up and could be used for many researches including biological activities of plant materials and change in composition of intestinal bacteria itself.