• PNF and Movement
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• v.13 no.1
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• pp.47-53
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• 2015

Purpose: This study examined the effects of space fabric type air insole pressure differences on young adults' dynamic balance ability. Method: The subjects of this study were 17 young female adults without musculoskeletal system disease. Balance ability was measured by dividing the subjects into three groups: an experimental group which did not wear an air insole (insole-off group), an experimental group which wore an air insole to which air pressure of $0.55kg/cm^2$ was applied (insole-0.55 group), and an experimental group which wore an air insole to which air pressure of $0.75kg/cm^2$ was applied (insole-0.75 group). For dynamic balance, the subjects stood on a balance pad, and perimeter length and medium speed were measured three times. The averaged values were recorded and statistically processed. Result: There were significant differences in average speed, and the insole-0.75 group's average speed decreased compared to the insole-off group and the insole-0.55 group. Although the total movement distance did not statistically differ, the insole-75 group's movement distance decreased compared to the insole-off group and the insole-0.55 group. Conclusion: Application of a space fabric type air insole, in particular insole-0.75, was helpful in improving balance ability. This is considered to occur because the space fabric structure was conducive to decreasing sway and producing balance.

• Fire Science and Engineering
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• v.16 no.4
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• pp.7-14
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• 2002

The diffusion characteristics of the smoke by effect of an ascending air movement in a local part of the room where heat generated was studied. How the smoke move in the limited parts of the room at which heat generated was studied through 3 cases altering locations of inlet and outlet of ventilated air and heat generated by CFD(Computational Fluids Dynamics) method. It was found that 1. Similar distribution of air velocity, air temperature and smoke concentration appeared in the case of upper left inlet and lower right outlet and the case of lower inlet and upper right outlet. 2. Distribution of temperature and smoke concentration was 0∼0.3, 0.06∼0.14 in the case of lower left inlet and upper right outlet. 3. the location of heat generation did not influence on the temperature distribution, but influence on the distribution of smoke concentration.

• Journal of the Korean Society of Marine Environment & Safety
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• v.6 no.1
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• pp.69-76
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• 2000

Bubble boom may be a good alternative for the prevention of oil spill pollution due to its easy deployment and clean post-process tasks. The present work is focused on the experimental investigation of air bubble movement for the bubble boom by visualization and quantitative PIV measurements. Bubble plume was generated by adjusting the pressure of pressure vessel ranging 6.7 kpa to 14.7 kpa. The results showed at lower inlet velocity and higher supply air flow rate that bubble boom maintained its containing capability reasonably well up to the maximum containing limit.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.6
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• pp.27-36
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• 2002

The objective of this study is to improve the quality of the atmospheric environment by incorporating the factors of meteorology and urban climate into the field of urban and environmental planning. To this end, we have conducted a study on CLIMATOP and the mapping of urban climate, which are basic data used to analyze changes in climatic factors and the stagnation and accumulation of air pollutants. In particular, we focused on understanding the formation and movement of cold fresh air and its influx into urban areas by measuring and analyzing climatic factors. As a study result, classification criteria far CLIMATOP and a urban climatic map were made. In addition, we analyzed a digital elevation model, climatic data, and isothermal curves. As a result, we identified the corridor through which cold fresh air moves. We also observed that the temperature of the fluxed cold fresh air increased as land use changed. When the results of this study are applied to urban re-development and re-building projects, which require preliminary environmental assessment and environmental impact assessment, the practice proposed by this study is expected to contribute to the natural purification of air pollution activating the movement of cold fresh air and its influx into urban areas.

• Fire Science and Engineering
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• v.32 no.6
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• pp.15-21
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• 2018

This study examined the flow characteristics of fire smoke under pressurized air ventilation conditions by carrying out fire simulations on multi-compartment enclosure, including room, ancillary room and stair case. Fire simulations were conducted for the air-leakage test facility, which was constructed to measure the effective leakage area and aimed to improve the understandings of fire and smoke movement by analyzing the overall behaviors of fire smoke flow and pressure distributions of each compartment. The simulation results showed that the heat release rate of the fires was controlled sensitively by the amount of air supplied by the ventilation system. An analysis of the velocity distributions between the room and ancillary room showed that fire smoke could be leaked to the ancillary room through the upper layer of the door, even under pressurized air supply conditions. From these results, it was confirmed that the fire size and spatial characteristics should be considered for the design and application of a smoke control system by a pressurized air supply.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12B
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• pp.1686-1697
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• 2011

This paper aims to build up a RFID-automated cargo movement system in an air-cargo warehouse. In our research, we do the spectrum measurements compliant with the RFID frequency bands to observe the interferences from legacy systems in the air-cargo warehouse. To overcome the dense-reader mode (DRM) problem, we apply three novel approaches, which are the periodic transmit of a reader, the Visible RFID reader & tag, and the sensor-based RFID system. Moreover, for the tag collision issue, we implement the Adaptive Adjustable Framed Q(AAFQ) algorithm, and the demonstration on RFID tag anti-collision algorithms show that the AAFQ algorithm has highly desirable tag anti-collision performance compared to any other commercially available solutions.

• Steel and Composite Structures
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• v.46 no.5
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• pp.669-672
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• 2023

In this research, the researcher has examined the factors affecting the movement of the soccer ball and will show that the effects such as air resistance, altitude above sea level, wind, air pressure, air temperature, air humidity, rotation of the earth, changes in the earth's gravitational acceleration in different areas. It, the geographical length and latitude of the launch point, the change of gravitational acceleration with height, the change of pressure with height, the change of temperature with height and also the initial spin (Magnus effect) affect the movement of projectiles (especially soccer ball). We modelled th ball based on shell element and derive the motion equations by energy method. Finally, using numerical solution, the wave of the ball is studied. The influences of various parameters are investigated on wave propagation of the ball. Therefore, in short, it can be said that the main factors that play a major role in the lateral deviation of the hit ball are the initial spin of the ball and the wind.

• Journal of Environmental Health Sciences
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• v.42 no.2
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• pp.133-140
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• 2016

Objectives: A pilot study was undertaken to assess the bioaerosol levels in restaurants and determine the effects of variations in temperature, relative humidity, and air movement on these levels. It focused on the differences between kitchens and dining areas, as well as between summer and winter. Methods: A field survey was performed in six restaurants. An Anderson type air sampler was used for sampling bioaerosols, such as total suspended bacteria (TSB), Gram-negative bacteria (GNB), Gram positive bacteria (GPB), opportunistic bacteria (OP), Staphylococcus spp., and total suspended fungi (TSF). Results: The average levels of TSB were $1{\times}10^2CFU/m^3$ and of TSF they were $1{\times}10^0{\sim}10^1CFU/m^3$. The kitchens had higher bioaerosol levels compared to dining areas, and summer showed much higher levels than winter. The concentration of OP in summer was more than six-fold that of winter. S. aureus was detected both in kitchens and dining areas, even in winter. The main effect of air movement on TSB levels was significant (p<0.05), as was air temperature, relative humidity and air movement on TSF levels (p<0.05). Conclusion: There was a wide variation in bioaerosol levels among different restaurants. The results indicate that cooking foods may be a key factor affecting bioaerosol levels. The effects of air temperature and relative humidity reveal that bioaerosol levels may vary according to the season. The observation of pathogenic bacteria suggests that the hygiene management of establishments should be improved. Future research is needed to characterize the relation between bioaerosol levels and the occupant density of the dining area.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.3
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• pp.247-253
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• 2002

In this study, reduced-scale experiments were conducted to analyze smoke movement in tunnel fire with roof vent. The 1/20 scale experiments were carried out under the Froude scaling using gasoline pool fire ranging from 7.3 to 15.4 cm in diameter with total heat release rate from 1.0 to 8.46kw. In case of 1 m high vent, smoke front reached to the tunnel exit at about 16 sec delayed with ventilation. The delay time grew longer with the vent height. The temperature after the vent was lower than that without the vent. The exit temperature declined maximum of $20^{\circ}C$ after passing the vent. It was confirmed that the thickness of smoke layer was maintained uniformly under the 25% height of the tunnel through the visualized smoke now by a laser sheet and the digital camcorder.

• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.1
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• pp.40-49
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• 2002

Floating fixed scroll adopted for tip sealing enhancement in a scroll compressor is always under the influence of tipping moment produced by internal gas forces. Unless the tipping moment is property compensated by some restoring moment, the fired scroll would suffer tipping movement, degrading the compressor performance. The condition on which the tipping movement of the fixed scroll can be suppressed has been investigated analytically. For no tipping movement, the floating fixed scroll should be suspended on the main frame at proper level. The upper limit of the stable suspension is the axial location of the o-rings adopted for a back pressure chamber sealing on the rear side of the fixed scroll, and the lower limit is the mid-height of the scroll wrap.