• Journal of Korean Association for Spatial Structures
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• v.4 no.4 s.14
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• pp.65-76
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• 2004

Walking loads are usually considered as nodal loads in the finite element vibration analysis of structures subjected to walking loads. Since most of the walking loads act on elements not nodes, the walking loads applied on the elements should be converted to the equivalent nodal walking loads. This paper begins with measuring walking loads by using a force plate equipped with load cells and investigates the characteristics of the walking loads with various walking rates. It is found that the walking loads are more affected by walking rates than other parameters such as pedestrian weight, type of footwear, surface condition of floor etc. The measured walking loads are used as input loads for a finite element model of walking induced vibration. Finally, this paper proposes the equivalent nodal walking loads that are converted from the walking loads acting on elements based on finite element shape functions. And the proposed equivalent walking loads are proved to be applicable for efficient analysis of floor vibration induced by walking loads.

• Journal of the Korean Solar Energy Society
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• v.29 no.6
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• pp.81-87
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• 2009

The purpose of this study is to evaluate of the outdoor thermal environment by building scale and block type as variable factors. In this study, 18 cases of office in central business district that have different condition are compared about their surface temperature, HIP(Heat Island Potential), and MRT(Mean Radiant Temperature). They are simulated with 3-dimension numerical simulation software named Hoyano-model. The output results contain visualized distribution chart and numerical data. The results of evaluation are as follows. (1)The surface temperature of the building becomes higher as building coverage ratio is higher but floor area ratio is lower. In same conditions, unified block type is maximum $3.2^{\circ}C$ higher than divided block type. (2)HIP shows different daily pattern as block type. During daytime, divided block type is much higher than unified block type but after sunset, it is changed. (3)MRT shows different distribution pattern as sunlight moves expecially at noon. (4)As the results of this study, cases that have high floor area ratio condition show lower surface temperature by tendency to stay low indoor temperature in office building and big rate of windows on building surface.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.415-427
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• 1993

The purpose of this study was to evaluate the thermoregulatory responses to postures under different environmental conditions and to obtain the basal information for standard clothing weight, indoor climates, and working condition. Two adult female (22.5yrs, 46kg) were participated in this study. The experimental conditions were divided into three groups ; 1) comfort($27{\pm}1^{\circ}C$, $60{\pm}10%$), 2) hot($34{\pm}1^{\circ}C$, $60{\pm}10%$), and 3) cold($21{\pm}1^{\circ}C$, $50{\pm}10%$) condition. The postures performed were as follows; standing, sitting on the chair, sitting on the floor, and supine on the floor. At each condition, subjective sensations, 12 points skin temperature, rectal temperature, total and local sweat rate, pulse rates, blood pressure, skin blood flow rate were measured. The results were as follows : 1. Rectal temperature was high significant among groups in order of supine, sitting on the floor, sitting on the chair, standing posture(p<0.01). 2. Skin temperature was high in part of contact with the surface of the floor or wall and the effect of posture was greater in peripheral temperature than torso temperature. Sitting on the chair and sitting on the floor posture showed higher peripheral temperature than standing and supine posture. And peripheral temperature was lower in supine posture than any other postures. 3. Total and local sweat rate were decreased in order of standing, sitting on the chair, sitting on the floor, supine posture. 4. Pulse rate and disastolic blood pressure were higher in standing posture than supine posture, and there was significant difference between two postures(p<0.001). 5. Blood flow rate of thigh was high in sitting on the chair and sitting on the floor posture and low in standing posture. Blood flow rate of leg was low in standing posture significantly(p<0.01). 6. In comfort and hot condition, temperature sensation and comfort sensation were higher in standing posture and lower in supine posture than any other postures. In cold condition, temperature sensation was lower and comfort sensation was higher in standing and supine posture than any other postures. And supine posture was appeared positive in hot condition and negative in cold condition. From this study, we confirmed the effects of posture on human thermoregulatory responses. Results indicate that even under same conditions and clothing weight, the insulation of clothing will be different to postures.

• Journal of Korean Society of Forest Science
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• v.81 no.1
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• pp.53-65
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• 1992

For elucidating effective methods of restoration of forest recreational sites where management goals are maintaining naturalness and conserving natural ecosystem, seeding, fertilization and soil surface treatment were used for four years at the devastated forest-floor. For restoration of forest-floor vegetation, factorial experiment was used with a split plot design(main plot : fertilization, subplot : soil surface${\times}$seeding) and a randomized complete block design (fertilization${\times}$seeding) at the Kwanaksan Aboretum, Anyang, Kyonggido. Results were summarized as follows : Soil surface softening with tipping and ripping and straw-mat mulching (70% coverage) treatment was effective on germination, survival and growth of seeded vegetation at devastated forest-floor. Especially, straw-mat mulching treatment was effective on soil surface stabilization and seedling's survival at eroded soil surface, while complete soil surface softening treatment was effective on germination, survival and early growth of tree species of late-successional series. Introducing seeds of native species of pioneer or early-successional series, with good growth capability in barren soil was effective on rapid restoration in devastated forest-floor with its soil surface previously compacted and its surviving seeds washed away. When the seeding and straw-mat mulching after partial soil surface softening with tipping and ripping treatment were employed, it took about three years to restore the devastated forest-floor where surface erosion had been undertaken for an extended period of time and where naturally surviving seeds of native species had been washed away. Softening treatment of soil surface was effective for about two years, and seeding and soil surface treatment increased number of seedlings and improved soil surface environment through fixing of movement of the fallen leaves. Fertilizing effect was not oberserved, mainly due to seeding exposure and poor physical condition including soil surface erosion, low soil water potential and drought, etc, at the field experimental site. However, application of nitrogen and phosphate fertilizers was effective on seedling survival of the species in late-successional series, while lime application adversely affected the seedling survival.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.1
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• pp.149-158
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• 1998

The purpose of this study was to investigate the effect of age on the human thermoregulatory responses and to obtain the basic information of the Korean thermophysiological characteristics under the traditional Korean floor heating system-Ondol. The participants consisted of 10 elderly women, 4 elderly men(over 65 years), 10 young women and 5 young men(in twenties). They were exposed to temperature-controlled Ondol room(20$\pm$1$^{\circ}C$, 50$\pm$5%R.H., floor surface temperature: 30$\pm$1$^{\circ}C$) for 60 minutes and wore the same experimental clothing. The postures were performed sitting and supine on the floor. In each pose, rectal temperature, skin.temperature of 10 areas, mean skin temperature, clothing microclimate, body fat were measured. The results were as follows; 1. The rectal temperature gradually decreased and mean skin temperature gradually increased in young and old groups in both supine and sitting pose on heated Ondol floor for 60 minutes. 2. Rectal temperature was different in each pose. The rectal temperature decreased 0.1$^{\circ}C$ in both groups under the condition of sitting and decreased 0.2'c in elderly group under the condition of supine. In supine pose, elderly group was more declined than young group. Mean skin temperature increased 0.5$^{\circ}C$ in both poses, both groups.

• Journal of Radiation Protection and Research
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• v.36 no.4
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• pp.174-182
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• 2011

With the reactor operation conditions - 4.3 wt% $^{235}U$ initial enrichment, burn-up 55,000 MWd/MTU, average power 34 MW/MTU for three periods burned time for 539.2 days per period and cooling time for 100 hours after shut down, to set up the condition to determine the minimum height (depth) of spent fuel storage pool to shut off the radiation out of the spent fuel storage pool and to store spent fuels safely, the dose rate on the specific position directed to the surface of spent fuel storage pool induced by the neutron and gamma-ray from spent fuels are evaluated. The length of spent fuel is 381 cm, and as the result of evaluation on each position from the top of spent fuel to the surface of spent fuel storage pool, it is difficult for neutrons from spent fuels to pass through the water layer of maximum 219 cm (600 cm from the floor of spent fuel storage pool) and 419 cm (800 cm from the floor of spent fuel storage pool) for gamma-ray. Therefore, neutron and gamma-ray from spent fuels can pass through below 419 cm (800 cm from the floor) water layer directed to the surface of spent fuel storage pool.

• 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 Safety
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• v.27 no.3
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• pp.9-14
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• 2012

The objectives of this study were to compare the results of HSL (Health and Safety Laboratory) ramp test with perceived sense of slip onto the several different floor surfaces under contaminated conditions. There are a variety of approaches from biomechanical measurements to psychophysical test and human perception. However, controversies over these approaches still remain. Some widely accepted methods need to be improved. AHP (Analytic Hierarchy Process) was used to evaluate the perception of slipperiness of seven different floor surfaces under the contaminated condition with glycerol solution. Twelve subjects worn same footwear and walked with self-selected step and cadence along the test floors. The angle of inclination obtained for water wet condition using 5 l/min with HSL ramp test was compared to perception of slipperiness. The surface roughness ($R_z$) related very well both AHP (r=0.95) and ramp test (r=0.92). The high significant correlation (r=0.90) was found between AHP and HSL ramp test.The HSL ramp test values (Coefficient of Friction, COF) according to subjective evaluation were divided into two categories. There were high correlations between test results (subjective evaluation, HSL ramp test) and surface roughness in Rz. Perception rating obtained with AHP showed a high correlation with COF obtained with HSL ramp test.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.389-394
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• 1993

A study on housing and management of dairy cows was conducted in three villages. All activities of husbandry related to the housing and the condition of the cows were observed and farmers were interviewed using a questionnaire. The main type of housing was a tie stall mostly in the back yard area with a gable or shed type roof. Inside the shed the temperature ranged from 17 to $29^{\circ}C$ and the relative humidity ranged from 62 to 73%. Drainage and manure handling was poor which lead to poor cleanliness of the stables and animal skins. The floor space was mostly wide and the roof level was low (less than 2.5 m). The slope of the floor (1-3%) was sufficient, the roughness of the floor was of medium quality. The shape and size of the feed trough was good with a surface of mostly irregular forms. Concentrate was mixed with water and offered in liquid form in pails made from plastic or from parts of rubber car tires. Hoof length was too long which could lead to unstable position and self injury. It is concluded that the housing conditions of dairy cattle need to be improved in order to improve the condition of the animals and the production performance.

• Journal of Conservation Science
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• v.35 no.1
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• pp.61-70
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• 2019

In this study, a scientific survey on the material of the mother-of-pearl floor mirror was conducted and conservation treatment processes were introduced. The survey results showed that the mother-of-pearl floor mirror in Daejojeon Hall of Changdeokgung is made of Dalbergia spp., and repair work seems to be done later with shorea spp. FT-IR analysis results showed that the varnishing is similar to the spectrum of lacquer. The metal wheels and metal line decorations set with mother-of-pearl were found to be made of brass based on XRF analysis, and the ingredient ratio showed that these were made in modern times. Foreign materials were stuck on the surface of the mother-of-pearl floor mirror before conservation treatment, which was in a structurally unstable condition owing to some missing submaterials. Conservation treatment was conducted on the damaged area to restore the mirror to its original appearance by using the same species of wood determined from the data obtained through the scientific survey.