• Journal of the Korean Society of Visualization
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• v.19 no.2
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• pp.15-25
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• 2021

Numerical studies on the hydrodynamics of a freely falling rigid sphere in bounded and unbounded water domains are presented having investigation on the drag coefficient, normalized velocity, surface pressure and skin friction coefficient as a function of time. Two different conditions of the bounded and unbounded domains have been simulated by setting the blockage ratio. Four cases of bounded domains (B.R. = 1%, 25%, 45%, 55%, 65% and 75%) have been taken, whereas the unbounded domain has been considered with 0.01%. In the case of the bounded domain (higher values of B.R.), a substantial reduction in normalized velocity and increase in the drag coefficient have been found in presence of the bounded domain. Moreover, bounded domains also yield a significant increase in the pressure coefficient when the sphere is partially submerged, but the insignificant effect is found on the skin friction coefficient. In the case of the unbounded domain, a significant reduction in normalized velocity occurs with a decrease in Reynolds number (Re) and also increase in the drag coefficient.

• Journal of the Korean GEO-environmental Society
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• v.24 no.12
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• pp.19-29
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• 2023

The main problem with roads is that cracks and settlement occur over time due to loads acting from the surface layer. One way to solve this problem is to use Geocell. Geocell can be used for structural reinforcement for erosion prevention, ground stabilization on flat and steep slopes, load bearing, and ground preservation. In this study, analyzed road pavement application cases using Geocell and purpose of this study is to analyze the bearing capacity of a road paving method including Geocell using field tests and LFWD(Light Falling Weight Deflectometer) equipment. In addition, the bearing capacity was compared and analyzed with the existing traditional road pavement method.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.506-510
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• 2005

As FPD technology is getting improved, there are a lot of issues on signal processing and analysis, and its relative importance has been increasing day by day. In particular, response time sad in the evaluation item of FPD has been measured by oscilloscope. In this paper, we propose an effective measurement method of response time in FPD. The proposed method is to calculate the rising/ falling time by using statistical techniques of histogram and analyzing an energy distribution. Ultimately, the method has proved the utility and reliability by comparison of oscilloscope

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.2
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• pp.244-255
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• 2023

Patterns abstractly depicting flowing water with Chinese characters such as gong, wan(man), or wang continued endlessly and curved water patterns began appearing on textiles during the Song Dynasty. Though Song curved water patterns encompassed poetic sentiments such as "falling flowers and flowing water," the meaning faded with time, and these patterns were depicted in backgrounds with flowers added to brocade (Geum-sang-cheom-hwa). During the Ming and Qing Dynasties, combinations of diverse patterns, including flowers, butterflies, dragons, and auspicious treasures became fashionable, rather than the gong- and wan-shaped curved water patterns. Likewise, during the Joseon Dynasty, curved water patterns were preferred as background rather than as primary patterns. They were overlaid with flowers and clouds. The overlaid flower patterns included four-season flower patterns (17th-18th centuries), round flower patterns (19th century), and large flower patterns (20th century), which were identical to flower patterns fashionable at the time and arranged at intervals on complex curved water pattern backgrounds. In contrast, simple Ruyi types were more numerous than the four-Ruyi types fashionable at the time with regard to cloud patterns. Added here were Taiji (great ultimate symbol) or crane patterns, thus seeking to depict diverse auspicious Ruyi such as wish fulfillment and longevity.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.6
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• pp.39-45
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• 2016

In this paper, analyzes the characteristics of self-weight consolidation on the dredged clay according to the fines content and falling height. Research was performed with the dredged clay sampled by Sae-mangeum field site. Classification of fines content was performed by sieve analysis test. After adjusting the fine content, self-weight consolidation tests were carried out focussing on the variation of fines content and falling heights. From the test results of the self-weight consolidation test, samples with high fines content had reached sedimentation completion more later than ones with less fine content samples. In other words, the start of self-weight consolidation was slowing down with increasing of fines content. Also, from the test results of calculating the coefficient of sedimentation consolidation, the coefficient value were increased with the fines content increases. In addition, the change of sedimentation ratio and volume ratio showed more higher changed value as the fine content increases. Thus, it is important to consider the fines content when estimate the settlement time of dredged soil in field dredge work.

• Solar Energy
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• v.19 no.2
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• pp.1-8
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• 1999

The heat transfer characteristics of ice storage system of falling film type using sprial coil is investigated. The experimental facilities consisted of a water tank, spiral coils located above the tank, an upper water distributor, and a circulating water pump. Water is distributed uniformally over the spiral coils and it forms falling thin films. In the process of freezing, ice is formed on outside of the spiral coils through recirculation of tank water. In the process of melting, ice is melted with return water from the heat load, while the water is chilled again and drops into the tank. The results of falling film type of ice thermal storage system are as follows. The highly efficient shower flowrates for icing is near $3{\ell}/min$. Icing rates on spiral coils is rosed while brine flowrates is increased. Lower brine temperature is not only increased freezing rates but. also become higher total icing weight and overall heat transfer coefficient. Smaller shower flowrates is obtained lower water temperature on outlet for a long time. The amounts of quantity can be detected more accurately by measuring storage tank weight.

• Culinary science and hospitality research
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• v.13 no.3
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• pp.158-165
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• 2007

This study was carried out to evaluate the rheological properties of cake flour with 3% of commercial multi-emulsifiers(P company, W company, O company) based on flour. Rheological properties were analyzed by Falling number, RVA, Alveograph and Farinograph. In Falling number, viscosity of cake flour with multi-emulsifiers was increased. In RVA, initial pasting temperature was increased by adding multi-emulsifier except for W company. and peak viscosity, final viscosity and setback were increased but breakdown was decreased. In Alveogram, P and P/L value were decreased but L and G value were increased. In Farinogram, water absorption was decreased but dough development time was increased and stability was increased except for P company.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.4
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• pp.781-788
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• 2013

In this paper, we introduce a quadruped robot-based alarm system for monitoring the emergency situation due to falling in the elderly. Quadruped robot includes the FPGA Board(Field Programmable Gate Array) applying a red-color tracking algorithm. To detect a falling of the elderly, a sensor node is worn on chest and accelerations and angular velocities measured by the sensor node are transferred to quadruped robot, and then the emergency signal is transmitted to manager if a fall is detected. Manager controls the robot and then he judges the situation by monitoring the real-time images transmitted from the robot. If emergency situation is decided by the manager, he calls 119. When the fall detection system using only sensor nodes is used, sensitivity of 100% and specificity of 98.98% were measured. Using the combination of the fall detection system and portable camera (robot), the emergency situation was detected to 100 %.

• Journal of East-West Nursing Research
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• v.5 no.1
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• pp.65-74
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• 2000

This study was attempted to show basic data for search of nursing intervention about sleep improving in home and institute elderly peoples. Research design was cross-sectional survey method for comparison of sleep patterns and another variables between home and institute elderly peoples. Subjects were sampled by purpose as home and institute elderly peoples at age of 65 or older in Seoul or nearly. The survey questionnaire was used by modification of sleep questionnaire which Kim, O, Song & Bak(1997) developed. Data were collected between December, 1999 and April, 2000. And data were analyzed by SPSS PC+ for purpose of research. Results are as follows: 1. Home and institute elderly peoples, all were change of sleep patterns and sleep pattern was showed early sleeping down. But institute elderly peoples slept earlier than home elderly peoples. 2. As rest of morning, difficulty of falling asleep and disturbance of re-asleep, subjective thinking and feeling were showed more negative thing home elderly peoples than institute elderly peoples. As frequency of falling asleep within 5 min in 1 week, frequency of falling asleep over 30 min in 1 week and frequency of awakening in a day, objective frequency were showed more insomnia institute elderly peoples than home elderly peoples. Home elderly peoples didn't nap most and institute elderly peoples napped on very short time. 3. Regarding sleep-disturbing factors, physical factor was popularly joint-disturbance in all, home and institute elderly peoples. Environmental factor was popularly noise, particularly institute elderly peoples. Emotional factor wasn't all. 4. Practiced strategies for better sleep was popularly TV/Radio in home elderly peoples and were popularly regular sleep and religious action in institute elderly peoples. From the results of this study, home elderly peoples need nursing intervention of improving self-satisfaction on sleep and institute elderly peoples need nursing intervention of decreasing falling asleep-disturbing and decreasing frequency of awakening in sleep.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.631-636
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• 2016

The purpose of this study was to test the effects of Tai Chi exercises on the grip power, pain and fear of falling in elderly persons. A quasi-experimental design was used. This study included 37 subjects who were living in C city. The subjects were divided into the experiment group (n=18) trained in the Tai Chi technique for 6 weeks and the control group (n=19). The experimental group practiced the 24 posture simplified form of Tai Chi for 6 weeks (5 times per day for 60 minutes each time). The effect of the treatment was measured by determining the grip power, pain and fear of falling before and after the 6 weeks of intervention. The experimental group showed a significant increase in grip power (P<0.001) and decrease in pain (P<0.001) compared to the control group. The fear of falling in the experimental group decreased significantly (P<0.002). Tai Chi exercises may be an effective intervention to prevent falling. The Tai Chi technique would therefore be a good method of improving the pain and body health index in elderly persons.