• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.4 s.44
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• pp.349-355
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• 1992

Comfortable sleeping largely depends on human mental state, physical condition, the temper. ature and humidity in bedrooms, and qualities of quilt and bedcover. Of the qualities of quilt, thermal insulation effect plays the most important role in keeping bedroom in ample temperature and preventing human body from giving off heat. In the present study, which is a sequel study to research on the thermal insulation effect, the real-size quilts with the following items of filling materials in them are designed to research on the variation of each item, and to measure the effect of the weight variation in inner covers on the thermal insulation effect of quilts, the results are as follows: 1. The coefficient between the weight of filling materials and the thermal insulation effect of quilt is shown to be a significant $0.91\~0.97$. 2. The thermal insulation effect of the quilts with in size of $0.5\;Kg/m^{2}$ is surveyed to be high in order down > polyester > cotton > wool. 3. The effect of the texture of inner covers on the thermal insulation effect of quilt is shown to be ignorably low. 4. The weight of filling materials is shown to be in correlation with the thermal insulation effect of quilts, and the estimated regression line has been obtained.

• Journal of the Korean Geotechnical Society
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• v.30 no.8
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• pp.39-47
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• 2014

Frost heaving and thawing settlement cause unexpected stress around buried pipelines, which results in deformation and permanent demage. A large scale laboratory test has been performed to observe deformation, stress, and temperature of a buried pipe during atmospheric temperature changes. From the experimental results, the stress concentrated around the buried pipe is inevitable and deformation is caused by the frost heaving. Even though backfill materials are sandy soils which are normally assumed to be non frost susceptible, it is revealed that frost demage can happen due to drainage condition, the level of ground water table, and water content.

• Tunnel and Underground Space
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• v.23 no.2
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• pp.130-140
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• 2013

In this study, scaled model tests were performed to investigate the stability of twin tunnels with small clearance, where the pillar widths were 0.5D and 0.25D, respectively. The tunnels were supposed to be constructed in anisotropic weathered rocks with $30^{\circ}$ inclined bedding planes, and the model tests were conducted under the condition of lateral pressure ratio, 1. Six types of test models which had respectively different pillar widths and support conditions were experimented, where crack initiating pressures, maximum pressures, failure modes of pillar and deformation behaviors around tunnels were investigated. The models with wider pillar were cracked under higher pressure than the models with shallower pillar. The models with lining support were cracked under higher pressure and showed less tunnel convergence than the unsupported models. The models with both lining and pillar reinforcement were proved to be most stable among the tested models. In particular, as the model of 0.25D pillar width with only lining support showed shear failure of pillar according to the existing bedding planes, so both lining and pillar reinforcement were thought to be indispensable in that case of tunnel.

• Journal of Animal Environmental Science
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• v.10 no.1
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• pp.37-46
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• 2004

In order to investigate the effect of floor condition on the fattening performance of cattle, sixteen finishing Hanwoo steers of weighting 570kg were fed for 16 weeks to slaughter on two types of sawdust bedding pen oriented to the south(SP) and the north(NP) then obtained following results. The floor condition of SP roofed by transparent material was dry and flat during overall experimental period, whereas, that of NP roofed by solid slate was muddy and rough even in summer and fall, and then frozen in winter period resulted in interfering with the locomotion and resting behavior of steers. Average daily dry matter intake of steers was not different between tow treatments, however, the average daily gain of steers in NP and SP was 0.64kg and 0.75kg, respectively, meaning that gained 14.3% less for the NP group(p<0.05), accordingly, feed requirement(feed/gain) and TDN/gain increased by 15.9% and 15.5%, respectively. No significant differences were found in slaughter weight, carcass weight, dressing percentage, meat yield index and meat quality traits between two treatments. In conclusion, this study revealed that poor floor condition of feeding pen could decrease weight gain and feed efficiency of cattle by increasing energy consumption for locomotion and conductive energy loss while resting on the floor surface. These results indicates that housing orientation of cattle shed and the selection of roof material are important factors in beef cattle production.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.2
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• pp.291-299
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• 1993

In this study, bedclimate was investigated depending on three bedquilts used on ondol in winter. The environmental room condition and the ondol surface temperature were maintained $20{\pm}1^{\circ}C$, $50{\pm}3%R$. H and $30{\pm}1^{\circ}C$, respectively. The materials of the experimental quilts were not different from each other. But the weights of cotton filler were 1.5, 3.0, and 4.5kg for the bedquilts. Two healthy young women were subjected for seven hour's sleep with two replications for this study. The results are as follows. 1) The range of temperature under the mattress was higher($38.5{\sim}43.2^{\circ}C$) than that of the temperature on the mattress($32.4{\sim}37.0^{\circ}C$) or that of the temperature inside the bedquilts($30.2{\sim}34.5^{\circ}C$). The humidity inside the bedquilts was 40~73%R.H. 2) The range of bedclimate which subjects feel comfortable were $33.6{\sim}37.1^{\circ}C$ on the mattress, $30.2{\sim}33.6^{\circ}C$, 42~67%R.H. inside the bedquilts. At this range, the mean skin temperature of the subjects was was $34.7{\sim}35.6^{\circ}C$. 3) When there was heating, the weight of mattress increased due to evaporation by heat from below, while wehght of other bedding increased. 4) The lower limbs are noted to be a good representative for the prediction of the skin temperature during sleep. 5) The thicker the bedquilt, the warmer and more humid the bedquilt, which induce frequent body movement during sleep, hence inferior comfort properties of bedquilts.

• International Journal of Highway Engineering
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• v.10 no.2
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• pp.115-124
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• 2008

This Study was investigated in main breakage types of 50 interlocking block pavements in apartment houses and evaluated on their performance. According to performance evaluation, maintenance control index of 9 aged interlocking block pavements ranged 7.9 to 8.9. These values meant that the condition of interlocking block pavements were still good. Therefore, it was concluded that the 10-year cycle of the block replacement recommended by Ministry of Construction & Transportation is necessary to reappraise. To objectively evaluate the performance of interlocking block pavements, this study presented the criteria of maintenance control by combining two maintenance control standards suggested by Ministry of Construction & Transportation and the Japan Interlocking Block Pavement Engineering Association. Also, this study suggested that the domestic standard is necessary to include durability standards and quality standards of joint filling materials and bedding sand layer for increasing expectation life and reducing maintenance costs of interlocking block pavements.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.285-298
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• 1992

In this study, bedclimate was investigated depending on various bedquilts used oin ondol in summer. The environmental room condition was maintained at 26: $1^{\circ}C,\;75{\pm}3\%$ R.H., while the ondol surface was kept at $25{\pm}1^{\circ}C$ without heating. The types of bedquilts were hemp, cotton, quilt made of polyester padding with polyester/cotton cover. Two healthy young women were subjected for seven hours' sleep with two replications for this study. The results are as follows. 1) The range of the temperature under the mattress ($25.2\~32.4^{\circ}C$) was lower than that of the temperature on the mattress ($28.8\~35.5^{\circ}C$), or that of the temperature inside the bedquilts ($30.3\~34.4^{\circ}C$). The humidity inside the bedquilts increased during sleeping, and the range of R.H. was $58\~80\%$. 2) The ranges of bedclimate which subjects feel comfortable were $30.5\~33.8^{\circ}C$ on the mattress, $31.0\~34.9^{\circ}C$, $61\~74\%$ R.H. inside the bedquilts. At this range, the mean skin temper-ature of the subjects was $34.3^{\circ}C\~35.2^{\circ}C$. 3) When there was no heating, the weight of the bedding increased during sleeping, and the weight increase was largest in the case of mattress. 4) There were correlations among the skin temperature of three points of the body (abdomen, thigh, foot) and the temperature and R.H. inside the bedquilt. 5) The effect of the type of bedquilts on the microclimate and physiolosical responses were significant. 6) Generally, when there was no heating, the body heat was transferred to the ondol floor, in summer, heat was transferred mostly through the mattress.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.341-345
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• 2011

This study was aimed to select the optimal mat condition using existing plant-mats for the efficient planting of bedding Chrysanthemum. At fifty days after cutting with Dendranthema grandiflorum 'Ford', root formation among the treatments using eight different mats outstood with the treatment using 10 mm thick coir net, which has medium inserted between mat layers - called C treatment, compared to other treatments; this treatment had the highest values in the plant height and shoot fresh weight, which were 29 cm and 5.6 g, respectively. On the contrary, in 40 days after transplanting root-formed mats to field, 12 mm thick jute net, which has medium inserted between mat layers, had the highest plants compared to other treatments. However, there was no significant difference in shoot weight compared to C treatment. In experiment of different lengths of cut, the results of growth after transplanting showed that 5 cm long cut performed best compared to 3 and 8 cm long cuts.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.382-389
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• 2011

BACKGROUND: Light-emitting diodes (LEDs) with lower electric cost and the specific wavelength have been considering as a novel light source for plant production in greenhouse conditions as well as in a closed culture system. Supplementary lighting for day-length extension was considered as light intensity, light quality, and/or photoperiod control on plant growth and development. Effects of supplementary blue or red LED radiation with lower light intensity on growth of Ageratum (Ageratum houstonianum Mill., cv. Blue Field), African marigold (Tagetes erecta L., cv. Orange Boy), and Salvia (Salvia splendens F. Sello ex Ruem & Schult., cv. Red Vista) were discussed during sunrise and sunset twilight in the experiment. METHODS AND RESULTS: Supplementary lighting by blue and red LEDs for 30 (Treatment B30; R30) or 60 (Treatment B60; R60) min. per day were established in greenhouse conditions. Photosynthetic photon flux for supplementary radiation was kept at $15{\mu}mol\;m^{-2}\;s^{-1}$ on the culture bed. Natural condition without supplementary light was considered as a control. The highest shoot and root dry weights were shown in African marigold exposed by red light for 60 min. per day. Supplementary blue and red lighting regardless of the radiation time significantly stimulated development of lateral branches in African marigold. Stem growth in Ageratum and Salvia seedlings was significantly promoted by red radiation as well as natural light. CONCLUSIONS: Extending of the radiation time at sunrise and sunset twilight using LEDs stimulated reproductive growth of flowering plant species. Different characteristics on growth under supplementary blue or red lighting conditions were also observed in the seedlings during supplementary radiation.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.317-322
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• 2009

Healthy seedling generation is the major concern in overcoming adverse effects of biotic and abiotic stresses during tender stage of development in vegetables and horticultural crops. Because of this, priority is given to research leading to the generation of healthy seedlings in crops subjected to transplanting and bedding. In this study, growth pouch experiments were conducted to determine the effect of inoculation of six different strains of Methylobacterium sp. namely, M. oryzae CBMB20, M. phyllosphaerae CBMB27, M. suomiense CBMB120, and Methylobacterium strains CBMB12, CBMB15 and CBMB17 on the seedling development of the vegetable crops cabbage, Chinese cabbage and cucumber; and horticultural crops tomato and red pepper. Crops treated with the test strains generally showed higher seedling dry matter accumulation compared to the control. Significantly higher accumulation was exhibited by CBMB12, CBMB17, and CBMB20 in cabbage, as well as for CBMB27 and CBMB120 on tomato and Chinese cabbage, respectively. Furthermore, all the strains promoted root elongation in cucumber and tomato seedlings while in Chinese cabbage and red pepper, root elongation was observed with CBMB120 and CBMB12 inoculation, respectively. Large scale nursery study is needed to develop a thorough protocol for healthy seedling development with the use of these strains.