• Journal of Advanced Marine Engineering and Technology
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• v.35 no.7
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• pp.914-920
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• 2011

For a hydro turbine electricity generation system in river or bay, a venturi system could be applied to accelerate flow speed at the inlet of the turbine system in a flow field. In this study, a steady flow simulation was conducted to understand the effect of venturi system on the acceleration of current speed at the inlet of a hydro turbine system. According to the continuity equation, the flow speed is inversely proportional to the cross-section area in a conduit flow; however, it would be different in an open region because the venturi system would be an obstruction in the flow region. As the throat area is 1/5 of the inlet area of the venturi, the flow velocity is accelerated up to 2.1 times of the inlet velocity. It is understood that the venturi system placed in an open flow region gives resistance to the upcoming flow and disperses the flow energy around the venturi system. The result of the study should be very important information for an optimum design of a hydro turbine electricity generation system.

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.1-18
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• 2005

The purpose of this study was to evaluate performance characteristics. in the success of team attack during volleyball competition. For this, real game was analyzed using S-VHS video camera for three dimensional cinematography. The contents of this research were receive to set time, set to spike time, setter moving distance, ball position during set and attacker's relative ball position during jump and spike, and open area at spike. Among the various kinematical factors considered in this study, the ball height relative spiker and open area were found to be related to offensive performance. This finding implies that although their direct impact were not significant the other factors could have indirect impact on offensive performance by increasing open area. Thus, receiver, setter, assistant attacker, and main attacker should practice for successful performance in each stage. Lastly, it is necessary to develop kinematic variables to evaluate performance characteristics of players. Further study may consider the best defense position against the attack of the opponent player.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.6
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• pp.1010-1017
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• 2013

Two-axial electrodynamic forces generated on a conductive plate by a partially shielded magnet wheel are strongly coupled through the rotational speed of the wheel. To control the spatial position of the plate using magnet wheels, the forces should be handled independently. Thus, three methods are proposed in this paper. First, considering that a relative ratio between two forces is independent of the length of the air-gap from the top of the wheel, it is possible to indirectly control the in-plane position of the plate using only the normal forces. In doing so, the control inputs for in-plane motion are converted into the target positions for out-of-plane motion. Second, the tangential direction of the open area of the shield plate and the rotational speed of the wheel become the new control variables. Third, the absolute magnitude of the open area is varied, instead of rotating the open area. The forces are determined simply by using a linear controller, and the relative ratio between the forces creates a unique wheel speed. The above methods were verified experimentally.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.43-47
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• 2019

In this study, capability of an air slot in a siphon spillway for controlling outflow discharge is investigated through hydraulic experiments. Arc and rectangular shapes of air slot are considered and the open area of air slot can be varied. Complex air-regulated flow occurs inside the the siphon spillway when the air slot is installed on it. The same discharge is measured at the same water level inside the reservoir when the water level rises or falls. Nondimensional discharge through the siphon spillway increases slowly as nondimensional open area of the air slot increases. The hydraulic experiments show that the control of outflow discharge of siphon spillway is possible by controlling the open area of the air slot.

• Journal of Chest Surgery
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• v.18 no.4
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• pp.746-752
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• 1985

A retrospective clinical observation was made of 40 patients with postoperative cerebral dysfunction among 2634 patients who underwent open-heart operations in Severance Hospital. Yonsei University between 1962, the year the first successful open heart operation was done, and June 1985. Suspected causes of brain damage were reviewed. Brain CT findings were evaluated in 24 patients. There were 15 cerebral infarcts, 4 intracerebral bleedings, 3 ischemic brain damages, 1 infarction with intracerebral hemorrhage and 1 diffuse cortical atrophy from unknown cause. The most frequent site of cerebral infarction was the middle cerebral artery area with no predilection on the right of left.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1D
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• pp.141-148
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• 2011

City of Incheon opened rapid transit(urban railroad line 1) in 1999 in order to relieve traffic congestion on major arterials. This research analyzed urban space changes of each station influenced area by examining the changes of residents, industrial employees, and floor area ratios before and after the open of Incheon urban railroad line 1. Analysis of variance was applied to change of station influence area. This research found out that the types of central business and agricultural station influence area had been changed significantly after the open of urban railroad. However, the residential, semi-residential, and suburban type of station influence area had not been changed after the open of urban railroad. Thus, it is necessary to provide diverse facilities for inducing residents and employees to the station influence area of residential and semi-residential. Furthermore, the suburban type of station influence area which is difficult to develop naturally by the law of Green Belt is needed to develop station influence area simultaneously with the construction of a station building.

• Journal of the Korean Society for Marine Environment & Energy
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• v.7 no.2
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• pp.64-69
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• 2004

The results of analyzing the hydrographic observations in the southwestern sea of Jeju Island in the last 10 days of August 1999 to investigate the characteristics of oceanic front area appeared in the East China Sea in August from is summarized as follows: In Line A, a front appears at Station A5 of 124°E and 31°30'N, showing relatively uniform density of 21.4 to 22.1 in the surface layer of 50m depth, which is distinguished from 22.0 shown in the sides of China and open ocean. In Line B, a front also appears at Station B6 of 124°E and 33°N, of which density is distinguished from 20.0 shown in the sides of China and open ocean as In Line A. As a result, the front area caused by fresh water runoffs from the Yangtze River in the East China Sea is formed at 124°E and 124°30'in the direction of east and northeast from Yangtze River, respectively. Nutrient concentrations in the study area are characterized by higher density in the side of China and by clear density difference between the upper and the lower layers in the side of open ocean, while by uniformly lower density concentration between the upper and the lower layers in the front area. Chlorophyll-α concentrations is high in the sides of China and open ocean, while low in the front area. Judging from the above results, the productivity in the front area is lower according to the inactivity of phytoplankton due to increased flow from vertical mixing between the upper layer and the lower layer. Also, the front area in the East China Sea in summer may be moved towards the adjacent sea of Jeju Island by increasing fresh water runoffs from the Yangtze River in summer.

• Journal of The Korea Institute of Healthcare Architecture
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• v.25 no.3
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• pp.47-55
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• 2019

Purpose: This study tries to propose the dimensions and area related to patient bed and surroundings in ICU considering nurses' observation and medical care. Methods: Literature survey, 11 Case studies, some Interviews with nurses and measuring of medical equipments' dimension in ICU have been mobilized in order to deepen the ICU bed area standards. Results: 0.3m clearance between head wall and patient bed is necessary for emergency cases. The minimum distance at the foot of the bed should not be less than 0.9m for EMR cart and medical tray. The clear floor area of one bed and surroundings in open ward is $10.2m^2(3m{\times}3.4m)$. In a single-bed patient room, the minimum clear floor area is $16.0m^2(4m{\times}4m)$. Considering the control of cross infection in ICU, Single bed patient room is recommended. Implications: The result of this study can be applied to the design of ICU and legislation of ICU standard.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.5
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• pp.53-63
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• 2009

This study aims at presenting a plan to build an open space network system in the city of Daejeon, assuming that parks and the green space system as a broad concept are to make a network by connecting open spaces such as parks, green spaces, squares, pedestrian roads, historical spots, etc. In the case of old downtown in Daejeon, this study examined the possibility of applying an open space network in the city of Daejeon and categorize them according to the findings from examining the case area, which enables to make a plan for building an open space network system in Daejeon. As a result, public offices and business buildings as an active open space have public open spaces in front of buildings and these front public open spaces are connected to pedestrian roads(gray open space). Since these pedestrian roads are consequently connected to large parks and rivers(green or blue open space), this overall spatial sequence can form an open space system. In addition, parks and green spaces, which have been fundamental elements so far, exist in relatively small and scattered areas at the center of the city. Hence, more parks and green space are needed to improve a park and green space system. However, it is very difficult to create new parks and green spaces in downtown, especially in old downtown areas. Therefore making an open space network system which spreads out over the whole city will form a healthy open space network in the downtown area.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.1
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• pp.50-54
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• 2012

According to Luhr's classification, a fracture in the mandible with a width of less than 15-20 mm is considered to be an atrophic mandibular fracture and its incidence is very rare. Because of the reduced cross-sectional area and smaller contact area of the fractured ends as well as the poorly vascularized bony structure and delayed bone healing, an atrophic mandibular fracture is a great challenge for oral and maxillofacial surgeons. Surgeons tend to perform closed reduction, because open reduction is considered a non-life-saving surgery among elderly patients. Thus, most of them have limited experience in surgical management. According to recent reports, open reduction yields a good result, and the Association for Osteosynthesis (AO) group has recommended open reduction. This is a case report of our two experiences of open reduction and rigid fixation of atrophic mandibular fractures by the AO principle. Articles were also reviewed here.