• 한국식생활문화학회지
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• 제9권4호
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• pp.335-340
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• 1994

The objective of this study was to determine effects of soybean oil(SO), cottonseed oil(CO) and ricebran oil(RO) on stability and flavor of yackwa. This study consisted of yackwa fried in 3 differnet oils, then stored for 0, 3, 6 weeks in normal wrap at room temp. or vaccum package at $4^{\circ}C$. The moisture, oil contents, Hunter color values(L, 'a' and 'b'), % free fatty acid(FFA), thiobarbituric acid(TBA) value and sensory scores for color, flavor and acceptability were analyzed. The foam height of the oil after frying was also determined. Yackwa fried in RO was more red('a'=11.43) than yackwa fried in SO(10.64) or CO(10.51). TBA value of yackwa showed no difference among frying oils. Yackwa fried in SO showed better acceptability than those fried in CO. Yackwa fried in RO showed similar acceptability to yackwa fried in SO. The % FFA and TBA value of yackwa averaged across oil and package showed increasing tendency during 6 weeks storage.

• 한국통신학회논문지
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• 제33권5A호
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• pp.517-525
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• 2008

본 논문은 균일한 도심지역에서의 CDMA 시스템의 상향링크에 대하여 송신전력, 간섭전력 및 블로킹 확률 등을 최소화하는데 기지국 배치에 따라 결정되는 셀 모양의 효과를 분석하기 위하여 시스템 수준의 모의실험이 이루어진다. 도심 마이크로 셀에서 기지국에 대한 경로 손실은 단말이 위치한 거리의 방향성에 영향을 받는다. 단말로부터 기준 기지국에 대한 간섭은 2차 Tier까지 고려된다. 간섭 계산의 정확성에 대한 손실 없이 계산 복잡도를 줄이기 위한 방법으로Wrap around method가 사용된다. 모의실험 결과는 송신전력, 간섭전력 및 블로킹 확률 등이 효율적인 기지국 배치에 따른 셀의 모양에 따라 줄어들 수 있음을 보여준다.

• 한국정밀공학회지
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• 제25권6호
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• pp.134-142
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• 2008

In this paper, we propose a precise linear motion stage supported by magnetically preloaded air bearings. The eight aerostatic bearings with rectangular carbon porous pads were located only one side of vertical direction under the platen where four bearings are in both sides of horizontal direction as wrap-around-design, and this gives simpler configuration than which constrained by air bearings for all direction. Each of the magnetic actuators has a permanent magnet generating static magnetic flux far required preload and a coil to perturb the magnetic farce resulting adjustment of air- bearing clearance. The characteristics of porous aerostatic bearing are analyzed by numerical analysis, and analytic magnetic circuit model is driven for magnetic actuator to calculate preload and variation of force due to current. A 1-axis linear stage motorized with a coreless linear motor and a linear encoder was designed and built to verify this design concept. The load capacity, stiffness and preload force were examined and compared with analysis. With the active magnetic preloading actuators controlled with DSP board and PWM power amplifiers, the active on-line adjusting tests about the vertical, pitching and rolling motion were performed. It was shown that motion control far three DOF motions were linear and independent after calibration of the control gains.

• Tribology and Lubricants
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• 제30권6호
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• pp.370-377
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• 2014

The basic elements in a rotary-type scroll compressor are two identical spiral scrolls containing refrigerant gas. The pressure variations in the compression pockets of a scroll compressor change the forces acting on the orbiting scroll, and these forces affect the dynamic behavior of the compression mechanism parts. To achieve high efficiency, using a self-sealing mechanism as a tip seal mechanism is very effective. Tip seals, which are placed on top of the scroll wraps, accomplish thrust sealing. This study calculates the friction force between the tip seal and the side plate of a scroll compressor using the numerical model considered in the Reynolds equation. The calculated friction force is verified by an experiment using a pin-on-disk apparatus. A hydraulic servo valve that controls the pressure of the oil hydraulic cylinder applies the normal load for the test, and a DC servo motor controls the sliding velocity of the disk. The friction force and normal load are measured by the force sensors attached to the supporting parts. The results show that the theoretical and experimental results are similar and that the friction is influenced by the viscosity of the oil and the sliding velocity of the scroll.

• 기본간호학회지
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• 제18권1호
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• pp.19-27
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• 2011

Purpose: This study was conducted to develop a respiratory nursing program using recorder playing for patients with asthma and to determine the effects of the program. Method: Participants were 26 patients with asthma (experimental group: 13, control group: 13). The experimental group participated in the respiratory nursing program for six months from April, to October, 2007. Content included playing a recorder, group education about asthma, and educational messages including cellular phone messages. The control group received usual care during the six months. Results: In this research the respiratory nursing program using recorders was developed in 3 stages: initial stage, advanced stage, and wrap up stage. Compared to the control group, fatigue status in the experimental group improved significantly as well as level of forced expiratory volume in 1 second. However significant differences were found in sleep status, mood, or quality of life. Conclusions: These results suggest that this respiratory nursing program for symptom management of patients with asthma led to improvements in self care activity. Nursing interventions are needed to maintain and further enhance the quality of life of these patients and the interventions should be implemented over a transition period.

• Steel and Composite Structures
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• 제19권2호
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• pp.441-465
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• 2015

This paper presents the experimental results of flexural and compression steel members strengthened with carbon fiber reinforced polymers (CFRP) sheets. In the flexural test, the five specimens were fabricated and the test parameters were the number of CFRP ply and the ratio of partial-length bonded CFRP sheets of specimen. The CFRP sheet strengthened steel beam had failure mode: CFRP sheet rupture at the mid span of steel beams. A maximum increase of 11.3% was achieved depending on the number of CFRP sheet ply and the length of CFRP sheet. In the compression test, the nine specimens were fabricated and the main parameters were: width-thickness ratio (b/t), the number of CFRP ply, and the length of the specimen. From the tests, for short columns it was observed that two sides would typically buckle outward and the other two sides would buckle inward. Also, for long columns, overall buckling was observed. A maximum increase of 57% was achieved in axial-load capacity when 3 layers of CFRP were used to wrap HSS columns of b/t = 60 transversely.

• 한국컴퓨터정보학회논문지
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• 제5권3호
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• pp.126-131
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• 2000

TCP는 인터넷에서 이미 많은 사용자들이 사용하고 있고 그 성능도 입증되어 왔지만, 망 구조의 급격한 변화에 따라서 TCP의 성능을 이에 맞게 개선하려는 노력들도 많이 제안되고 있다. 특히, 망이 고속화되고 위성링크 등에서 지연이 증가하면서 Bandwidth-Delay Product도 상당히 커지게 되었다. 이에 대응시키기 위한 방법으로 TCP 옵션에 Window Scale Option과 TimeStamp option, 및 PAWS(Protection Against Wrap Sequence Numbers) 등을 추가하는 방법이 제안되었다. Bandwidth-Delay Product가 큰 망에서는 TCP의 윈도우 크기도 증가하게 됨으로, 현재 사용중인 TCP의 곱 감소 선형적인 증가 방식으로는 망 내의 버퍼 언더플로우 및 망의 불안정을 야기하여, 결국은 TCP처리율의 감소를 초래하게 된다. 그러므로, 본 논문에서는 위와 같이 윈도우 크기가 큰 망에서의 TCP 흔잡제어 알고리즘을 개선하기 위한 방법으로 TCP의 TimeStamp 옵션을 이용하여 윈도우 크기를 조절하는 혼잡제어 방안을 제시하였다.

• Advances in concrete construction
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• 제5권5호
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• pp.539-561
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• 2017

In this study, the effects of initial damage of concrete columns on the post-repair performance of reinforced concrete (RC) columns strengthened with carbon-fiber-reinforced polymer (CFRP) composite are investigated experimentally. Four kinds of compression-damaged RC cylinders were reinforced using external CFRP composite wraps, and the stress-strain behavior of the composite/concrete system was investigated. These concrete cylinders were compressed to four pre-damaged states including low -level, medium -level, high -level and total damage states. The percentages of the stress levels of pre-damage were, respectively, 40, 60, 80, and 100% of that of the control RC cylinder. These damaged concrete cylinders simulate bridge piers or building columns subjected to different magnitudes of stress, or at various stages in long-term behavior. Experimental data, as well as a stress-strain model proposed for the behavior of damaged and undamaged concrete strengthened by external CFRP composite sheets are presented. The experimental data shows that external confinement of concrete by CFRP composite wrap significantly improves both compressive strength and ductility of concrete, though the improvement is inversely proportional to the initial degree of damage to the concrete. The failure modes of the composite/damaged concrete systems were examined to evaluate the benefit of this reinforcing methodology. Results predicted by the model showed very good agreement with those of the current experimental program.

• PNF and Movement
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• 제13권3호
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• pp.155-162
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• 2015

Purpose: The current study (case report) seeks to examine the effects of a proprioceptive neuromuscular facilitation (PNF) exercise program on the upper extremity function and activities of daily living (ADLs) in a stroke patient. Methods: The subject was a 42 year-old woman diagnosed with right-sided hemiplegia due to stroke. Exercise therapy was provided for 50 minutes per day (5-minute warm-up, 40-minute exercise, 5-minute wrap-up) three times per week for a four-week period. The manual function test (MFT) was used to evaluate upper extremity functions. The modified Barthel index (MBI) was utilized to measure ADL. Results: After intervention using various PNF program, the MFT score increased from 23 to 26 and the MBI score increased from 62 to 66. Conclusion: After the application of the PNF program, the MFT and MBI scores increased. As compensative movement of the upper extremities declined, the movement of the upper extremities became faster and softer.

• 한국수소및신에너지학회논문집
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• 제30권4호
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• pp.338-346
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• 2019

During last years, hydrogen refueling infrastructure test and devices research for hydrogen station presented a significant growth consisting of the commercialization of fuel cell electric vehicles (FCEVs). However, we still have many challenges for making commercial hydrogen stations such as increased safety and cost reduction. This study demonstrates the low cost hydrogen storage tank (type 2) and effective winding method for high pressure hydrogen storage. We use numerical analysis to verify stress changes inside the wire according to the winding condition. Also liner size, winding wire size and wire tension were studied for the safety and cost down. Results show that the stress of winding wire decreased with increased winding angle and increased the liner diameter. On the other hand, the stress of winding wire increased according to the increased wire thickness and tension.