• 한국축산시설환경학회지
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• 제12권2호
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• pp.85-94
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• 2006

The effects of turning frequency of in-vessel composting on ammonia emissions during composting of separated solids from swine slurry/sawdust mixtures and performance of biofiltration using the chicken manure compost were investigated. Separated solids from swine manure amended with sawdust was composted in a 226 L laboratory-scale in-vessel reactors under various turning frequency and continuous airflow (0.6 L/min.kg.dm) for three weeks. Three laboratory-scale manure compost biofilters were built to treat effluent gas from the composting of separated solid from swine manure amened with sawdust process. These experiments were continued over a period of three weeks. The composting of separated solid swine manure amended with sawdust and manure compost biofiltration system were evaluated to determine the turning frequency type that would be adequate for the rate of decomposition and compost odour reduction. The compost odour cleaning was measured based on ammonia gas concentration before and after passing through the manure compost biofilter. The average ammonia odor reduction in the manure compost biofilter was 96.9 % at R1 (no turning), 99.4 % at R2(once a day turning) and 89.0 % at R3(twice a day turning), respectively. The efficiency of ammonia reduction was mainly influenced by the turning frequency.

• PNF and Movement
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• 제9권1호
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• pp.65-73
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• 2011

Background : This study was to investigate effect of hot and cold water for the hand dexterity. Methods : A total of 37 subjects having hemiplegia(men=6, women=11) and normal(men=10, women=10) were participated in this study. After both hands was soaked in the small tube for 1 minute, we measured 'making dots in circles(BOTMP)', 'lifting small objects(JHFT)', 'disk turning(MMDT)' test. Results : In the case of normal's dominant hand, there were statistically significant differences in all tests after soaked in the hot water but there were statistically significant differences in 'disk turning' test after soaked in the cold water. In the case of hemiplegia's unaffected hand, there were statistically significant differences in 'disk turning' test after soaked in the hot water but there were statistically significant differences in 'making dots in circles', 'disk turning' test after soaked in the cold water. In the case of hemiplegia's affected hand, there were statistically significant differences in 'lifting small objects', 'disk turning' test after soaked in the hot water but there were statistically significant differences in 'making dots in circles', 'disk turning' test after soaked in the cold water. Conclusion : The hot and cold water were affected in the hand dexterity. Especially, in the case of both normal and hemiplegia, there were statistically significant differences in 'disk turning' test after soaked in the cold and hot water. Therefore, We were founded that affected in gross movement than fine movement.

• 수산해양기술연구
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• 제42권2호
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• pp.111-118
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• 2006

It is indispensable to grasp the turning ability of a ship to operate her effectively. For this purpose, the author measured the turning ability of training ship, A-RA by use of bow thruster and stem rudder. The turning ability of this ship, in case of using both of stem rudder and bow thruster at the same time, caused by increase of steering angle provides more influence to the size of tactical diameter than it caused by the power of bow thruster. But the influence of bow thruster on the turning ability is available only within rudder angle $5^{\circ}\;-\;10^{\circ}$, so it is possible to grasp that the effect of bow truster is reduced as rudder angle become bigger. In case of the influence of bow thruster by her speed, the ability of bow thruster is very effective at low speed, but it is almost not available in normal turning speed. Therefore, the using both of stem rudder and bow thruster can be useful in case of low speed proceeding at entrance or departure of the narrow waterway or inside port which sea traffic is congest for collision avoidance.

• 해양환경안전학회지
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• 제18권6호
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• pp.591-596
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• 2012

안전하며 친환경적인 근해운송시스템을 확보하기 위해서는 운송 수단인 선박의 안전한 운항 확보가 필수적이다. 특히 좌초, 충돌 등의 해난사고를 방지하기 위해서는 선박이 우수한 조종성능을 갖는 것이 요구되며 특히 조종성능 중에서 선회성능은 충돌 회피 등에 필수적인 성능이다. 본 연구에서는 선박에 부착된 조타기의 타력 증가가 선박의 선회성능에 미치는 영향을 모형선 실험을 통하여 고찰하였다. 먼저 Coanda 효과를 이용한 고 양력 타 장치 모형과 47 K PC의 모형선을 제작하였다. 또한 모형선의 선회 성능 실험을 위한 자유항주시스템을 구축하고 사각 수조에서의 타력 증가 값을 변화시켜가면서 모형선의 선회 성능을 계측하여 타력 증가에 따른 선회 성능의 변화를 평가하였다. 모형선의 선회성능 실험결과를 통해 타력 증가가 근해운송 선박의 선회 성능 향상에 효과적인 것을 확인하였다.

• 수산해양기술연구
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• 제35권3호
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• pp.209-214
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• 1999

The turning circle of a ship is the path followed by her center of gravity in making a turn of 360$^{\circ}$degrees or more with helm at constant angle. But generally it means her path traced at full angle of the rudder. For the ordinary ship the bow will be inside and the stern outside this circle.It has been usually understood that the turning circle is not essentinally affected by ship's speed at Froude numbers less than about 0.30. However, it is recently reported that the speed provide considerable effects upon the turning circle in piloting many ships actually at sea. In this paper, the author analyzed what effects the speed could provide on the turning circle theoretically from the viewpoint of ship motions and examined how the alteration of the speed at Froude no. under 0.30 affect the turning circle actually, through experiments of actual ships of a small and large size.The main results were as follows.1. Even though ship's speed at Froude no. under 0.30, the alteration of the speed affects the turning circle considerably.2. When the full ahead speeds at Froude no. under 0.30 of small and large ships were increased about 3 times slow ahead speeds, the mean rates of increase of the advances, tactical diameters and final diameters of thease ships were about 16%, 21% and 19% respectively.3. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3 times slow ahead speed, the mean rate of increase of the turning circle elements of large ships was greater 10% than that of small ships. 4. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3times slow ahead speeds, the mean rates of increase of the tactical diameter and final diameter of thease ships were greater than that of the advances of thease ships. 5. When only alteration of speed or sip's head turning is the effective action to avoid navigational fixed hagards, reducing the speed is always more advantageous than increasing the speed in order to shorten fore or transverse distance.

• 수산해양기술연구
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• 제35권3호
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• pp.210-210
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• 1999

The turning circle of a ship is the path followed by her center of gravity in making a turn of 360$^{\circ}$degrees or more with helm at constant angle. But generally it means her path traced at full angle of the rudder. For the ordinary ship the bow will be inside and the stern outside this circle.It has been usually understood that the turning circle is not essentinally affected by ship's speed at Froude numbers less than about 0.30. However, it is recently reported that the speed provide considerable effects upon the turning circle in piloting many ships actually at sea. In this paper, the author analyzed what effects the speed could provide on the turning circle theoretically from the viewpoint of ship motions and examined how the alteration of the speed at Froude no. under 0.30 affect the turning circle actually, through experiments of actual ships of a small and large size.The main results were as follows.1. Even though ship's speed at Froude no. under 0.30, the alteration of the speed affects the turning circle considerably.2. When the full ahead speeds at Froude no. under 0.30 of small and large ships were increased about 3 times slow ahead speeds, the mean rates of increase of the advances, tactical diameters and final diameters of thease ships were about 16%, 21% and 19% respectively.3. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3 times slow ahead speed, the mean rate of increase of the turning circle elements of large ships was greater 10% than that of small ships. 4. When the full ahead speeds at Froued no. under 0.30 of small and large ships were increased about 3times slow ahead speeds, the mean rates of increase of the tactical diameter and final diameter of thease ships were greater than that of the advances of thease ships. 5. When only alteration of speed or sip's head turning is the effective action to avoid navigational fixed hagards, reducing the speed is always more advantageous than increasing the speed in order to shorten fore or transverse distance.

• 한국항해항만학회지
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• 제27권5호
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• pp.465-471
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• 2003

내항 탱커가 비교적 정온한 해역에서 타선을 피하기 위해 대각도 조타론 행한 결과, 선회 중에 전복하는 사고가 발생하였다. 저자들은 전 논문에서 비중량이 큰 액체화물의 자유표면영향에 의한 중심상승과 전진 항해 중에 발생하는 선체 침하와 이로 인하여 생기는 선체 트림의 변화 때문에 발생하는 복원력 감소를 고려하여 사고선박의 복원력 곡선을 계산하였다. 본 논문에서는 먼저 전복사고를 당한 선박의 모형선을 제작하여 자항 선회실험을 실시하고 전복선박의 정상 선회시의 선회반경, 편류각 및 선속을 계측한다. 그리고 자항 선회실험을 통하여 얻은 선회반경, 선속 및 횡 편류각을 기초로 하여 각 경사각에 따른 측 압력과 경사 모멘트에 관한 실험을 실시하고, 갑판상 해수 침입이 측 압력과 경사 모멘트에 미치는 영향에 대해서 파악한다. 마지막으로 선회시 해수 침입으로 인해 발생하는 외측 경사 모멘트와 측압 중심의 변화론 조사함으로써 전복사고가 발생한 저건현 내항 탱커의 복원성에 대하여 검토를 하였다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2006년 추계학술발표대회 개요집
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• pp.265-267
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• 2006

• Ocean Systems Engineering
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• 제10권1호
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• pp.1-23
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• 2020

Hydrodynamic Drag of Surface combatants pose significant challenges with regard to fuel efficiency and exhaust emissions. Stern flaps have been used widely as an energy saving device, particularly by the US Navy (Hemanth et al. 2018a, Hemanth Kumar and Vijayakumar 2018b). In the present investigation the effect of flap turning angle on drag reduction is numerically and experimentally studied for a high-speed displacement surface combatant fitted with a stern flap in the Froude number range of 0.17-0.48. Parametric investigations are undertaken for constant chord length & span and varying turning angles of 5° 10° & 15°. Experimental resistance values in towing tank tests were validated with CFD. Investigations revealed that pressure increased as the flow velocity decreased with an increase in flap turning angle which was due to the centrifugal action of the flow caused by the induced concave curvature under the flap. There was no significant change in stern wave height but there was a gradual increase in the stern wave steepness with flap angle. Effective length of the vessel increased by lengthening of transom hollow. In low Froude number regime, flow was not influenced by flap curvature effects and pressure recovery was marginal. In the intermediate and high Froude number regimes pressure recovery increased with the flap turning angle and flow velocity.

• The Journal of Korean Physical Therapy
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• 제32권2호
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• pp.101-106
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• 2020

Purpose: This study examined the effects of the directions of neck rotation on the muscle activity of the upper trapezius and lower trapezius while rotating a shoulder externally. Methods: Twenty-five healthy males participated in this study. The subjects were asked to rotate their shoulder externally with 90° shoulder abduction and 90° elbow flexion in three different neck rotations (neutral, ipsilateral, and contralateral) in the prone position. The muscle activities of the upper and lower trapezius were measured using surface electromyography. One way repeated measures ANOVA was used to compare the muscle activity of the upper and lower trapezius depending on the different neck turning directions. Results: In the upper trapezius, turning the neck in the ipsilateral direction while turning a shoulder externally decreased the muscle activity significantly, but the muscle activity was increased significantly by turning the neck in the contralateral direction. On the other hand, in the lower trapezius, turning the neck in the ipsilateral direction increased the muscle activity significantly, but the muscle activity was decreased significantly by turning the neck in the contralateral direction decreased it significantly. Conclusion: When someone has an imbalance of shoulder function, turning the neck in the ipsilateral direction while turning the shoulder externally in the prone position is effective in decreasing the activity of the upper trapezius and increasing the activity of the lower trapezius. Therefore, these results could be used as basic evidence for researching patients with shoulder problems.