• 수산해양기술연구
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• 제47권1호
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• pp.37-45
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• 2011

Reduction of ship's rolling is the most important performance requirement for improving the safety of the crew on board and preventing damage to cargo as well as improving the comfort of the ride. It is a common experience for mariners, to see that steering with a rudder generally induces rolling of the ship, though the original aim of the rudder is to keep the ship's heading to the required course. At the first stage, when a rudder is steered, usually a ship heels in an inward direction, due to the roll moment acting on the rudder. At the next stage in steering, the main heel may change to an outward. This coupling between rudder and roll motion has become an attractive problem from the point of view of roll stabilization using the rudder, because it is a natural in sight that if the rudder action is skillfully related to the change of roll as well as to the course deviation, the roll can be reduced to a certain degree. The main aim of this paper is to discuss the results of the actual full-scale sea trials carried out on steer gear No.1 and No.1 2, the individual quartermaster and to make clear their statistical properties, using the actual data which included measurement of roll angle, roll rate and the comparative tests were carried out immediately after each other, in order to minimize any statistical variation in sea conditions. It can be concluded that the steer gear No. 1 2 reduced the roll motion on average by about 21% in comparison with the No.1 and confirmed the some difference as per a ability of quarter-master's maneuver.

• 한국축산식품학회지
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• 제29권1호
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• pp.82-90
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• 2009

This study was carried out to evaluate the effects of microwave power level on cooking properties of ground pork patties (fat level: 20%). Each patty was cooked from a thawed state to $76.7^{\circ}C$ (center temperature) in a microwave oven with power levels of 40% (360 W), 60% (540 W), 80% (720 W), and 100% (full power, 900 W), respectively. Cooking rate increased with power level, and the non-uniformity also increased with time during cooking. Overheating at the edge of the patties was observed for all power levels, and maximum temperature differences in between the edge position and center position were found in patties cooked at the 900 W power level. Compositional properties, total cooking loss, and drip loss were not affected by power level, although moisture content was lower at the edge than at the center position. As the power level increased, the reduction in patty diameter of cooked patties increased while the reduction in patty thickness decreased. Pork patties cooked at lower power levels (360 W and 540 W) had higher shear force values than those cooked at higher power levels (720 W and 900 W). Few changes were observed in instrumental color values.

• 대한두개안면성형외과학회지
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• 제13권2호
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• pp.147-150
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• 2012

Purpose: Varicella-zoster virus (VZV) infection is a common childhood disease. However, old and immune compromised patients are also at risk. Necrotizing fasciitis is a life threatening infection of the subcutaneous tissues, rapidly extending along the fascial planes. It is associated with a significant mortality rate, reported between 20% and 50%, and is therefore regarded as a surgical emergency. The authors treated a patient, who developed skin necrosis of her nose and left hemifacial area, following VZV infection. There are few literatures concerning this case; therefore, we present a rare case with review of literature. Methods: A 39-year-old woman had shown a localized, painful, multiple bullae and eschar formation in her nose and left hemifacial area for several days. Her skin lesion had rapidly worsened in size and morphology. Results: We diagnosed her as a necrotizing fasciitis, following herpes zoster, and then we performed a debridement of necrotic tissue and took a full thickness skin graft on her nose and left hemifacial area. Now, she was followed up with acceptable aesthetic result after 6 months. Conclusion: Secondary bacterial skin infection following VZV, can cause a result in a higher risk of complications. Among the complication, a necrotizing fasciitis of the head and neck is uncommon, and involvement of the nose is even more rare. Through this uncommon case report, we intend to emphasize the fact that early diagnosis of necrotizing fasciitis is very important, since it frequently necessitates surgical treatment which improves morbidity and leads to good recovery.

• 대한전자공학회논문지SP
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• 제37권6호
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• pp.9-16
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• 2000

최근 컴퓨터의 급속한 보급에 따라 고밀도 CRT(cathode ray tube)가 요망되고 있다. 이를 위하여 신호 대역과 주사 속도의 증가에 따른 주사선 수를 증가 시켜야 하고 플리커(flicker)도 줄여야 한다. 플리커 현상은 PC작업을 장시간 하는 경우 더욱 심하게 느껴지므로 플리커 현상을 줄이는 연구가 필요하다. 본 논문에서는 플리커가 덜 느껴지도록 하는 디스플레이 시스템의 설계를 위한 기초 연구로서 CRY에 사용된 인광체의 잔광 특성 및 화면의 밝기에 따른 플리커와 프레임 주파수와의 관계를 정량적으로 해석하였으며, 또한 디스플레이 전화면에 대해서 시각을 고려하여 플리커를 덜 느끼도록 하는 프레임 주파수를 제시하였다.

• 한국가정과교육학회지
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• 제4권1호
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• pp.57-75
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• 1992

The purpose of this study was to survey the actual condition of education on the western clothing construction in Home Economics and Housework curriculum of high school. And the finding of this study will the helpful to the persons in authority who take part in the course of compilation of the western clothing contruction. The subjects of this study were 101 high school teachers in Chonbuk province. Their responses to the questionaires were analyzed by frequencies and percentiles. The major findings of the study were as follows. 1. Most high school had only a little educational facilities for learning of clothing construction of, if any, they could only show examples in practice. 2 In case of making clothes, students who sew by hand carried out drafting and cutting on their desks in the classroom. When they have practical training, 56.4% of them cheese only one of one-piece dress trousers, and skirt which are presented in the textbook. The related teachers indicated that content composition of the texbook was not fit for the purpose of the students level, and also pointed out the deficiencies of educational facilities, lack of teacher’s research and training, and lack of school hours of evaluation, practical skill was performed in parallel with paper-test at 73.3%. 3. Pajamas and one-piece dress presented in the textbook were the most suitable for the practice at 64.7%. They hoped that illustrations in textbook are so large and full that clothes made through the practice can be worn. Also they hoped that their opinions and wearable guidance will be reflected in the textbook. They emphasized the need of western clothing construction unit because of acquistion of elementary knowledge. The current amount of content composition was enough or excessive. In addition, they understood the curriculum of high school is rather closely connected with that of middles school. Their recognition of the rate of difficulty is very similar to that of other school teachers. They recognized the goal of learning should be applied to the real home life.

• 한국초전도ㆍ저온공학회논문지
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• 제14권2호
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• pp.24-27
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• 2012

The superconducting coil system is one of the most important components in Korea Superconducting Tokamak Advanced Research (KSTAR), which has been operated since 2008. $Nb_3Sn$ and NbTi superconductors are being used for cable-in-conduit conductors (CICCs) of the KSTAR toroidal field (TF) and poloidal field (PF) coils. The CICCs are cooled by forced-flow supercritical helium about 4.5 K. The temperature, pressure and mass flow rate of the supercritical helium in the CICCs are interacting with each other during the operation of the coils. The complicate behaviors of the supercritical helium have an effect on the operation and the efficiency of the helium refrigeration system (HRS) by means of, for instance, pressure drop. The hydraulic characteristics of the supercritical helium have been monitored while the TF coils have stably achieved the full current of 35 kA. In other hands, the PF coils have been operated with various pulsed or bipolar mode, so the drastic changes happen in view of hydraulics. The heat load including AC loss on the coils has been analyzed according to the measurement. These activities are important to estimate the temperature margin in various PF operation conditions. In this paper, the latest hydraulic behaviors of PF coils during KSTAR operation are presented.

• 한국양식학회지
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• 제19권2호
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• pp.95-98
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• 2006

This study was performed to determine possibility of compensatory growth of juvenile olive flounder fed a commercial feed during the summer season. Five treatments of fish with triplicates were prepared: C, S1, S2, S3 and S4. Fish in the control group (C) was hand-fed with the commercial feed to apparent satiation twice daily for 6 days a week during 6 weeks. Fish in S1, S2, S3, and S4 experienced 1, 2, 3, and 4 weeks of starvation before fed to satiation twice daily for 5, 4, 3, and 2 weeks, respectively. The feeding trial lasted far 6 weeks. Survival of flounder in C, S1 and S2 was significantly (P<0.05) higher than that offish in S4. Weight gain and specific growth rate (SGR) of flounder in C and S1 were significantly (P<0.05) higher than those of fish in S2, S3 or S4. And weight gain and SGR of flounder in S2 and S3 were significantly (P<0.05) higher than those of fish in S4. Feed consumption of flounder tended to increase with weeks of feeding. Feed efficiency ratio and protein efficiency ratio for flounder in C, S1, S2 and S3 were significantly (P<0.05) higher than those for fish in S4. Moisture content of the whole fish in C was lowest, but highest for fish in S4, respectively. Crude protein content of the whole fish in C was highest, but lowest far fish in S4, respectively. Crude lipid content of the whole fish in C, S1 and S2 was significantly (P<0.05) higher than that of fish in S4. In conclusion, full compensatory growth was obtained in juvenile olive flounder fed for 5 weeks after 1-week feed deprivation during the summer season. Compensatory growth of fish was well supported by improvement in feed efficiency ratio and protein efficiency ratio.

• 대한산업공학회지
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• 제35권2호
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• pp.141-149
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• 2009

As the number of personal computers installed in vehicles increases, a touchpad often used in a labtop computer can be used for the control of an in-vehicle information system (IVIS). Using a touchpad to control the system allows the user to select among large amount of information with a single touch of dragging. For safety and convenience of a driver, the touchpad could be placed on a steering wheel. This research is designed to calculate the most efficient Control-Response Ratio (C/R ratio) for the menu interaction of a touchpad on a steering wheel. Since the menu pointer's rate of movement and proper C/R ratio is determined by the amount of selected information, the amount of displayed information and the movement of a menu pointer was chosen to be independent variables. The dependent variables are a user's preference and task completion time. Two factor full factorial within subject design was used 16 subjects. The investigation revealed that the amount of selected information increased with increasing C/R ratio. The movement of the pointer became slower as the amount of information increased. The best C/R ratio was calculated for each amount of information and preference regression of the user's preference was drawn accordingly. Through this research, the automobile interior designer can benefit from the guidelines suggested for the touchpad control.

• Advances in environmental research
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• 제2권1호
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• pp.19-33
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• 2013

Microalgae are receiving an increasing attention because of their potential use as $CO_2$ capture method and/or as feedstock for biofuels production. On the other hand the current microalgae-based technology is still not widespread since it is characterized by technical and economic constraints that hinder its full scale-up. In such contest the growth kinetics of Nannochloris eucaryotum (a relatively unknown marine strain) in batch and semi-batch photobioreactors is quantitatively investigated with the aim of obtaining the corresponding kinetic parameters suitable for process engineering and its optimization. In particular the maximum growth rate was evaluated to be 1.99 $10^{-3}\;h^{-1}$. Half saturation concentrations for nitrates ($K_N$) and phosphates uptake ($K_P$) were evaluated as 5.4 $10^{-4}\;g_N\;L^{-1}$ and 2.5 $10^{-5}\;g_P\;L^{-1}$, respectively. Yield factors for nitrogen ($Y_N$) and phosphorus ($Y_P$) resulted to be 5.9 $10^{-2}\;g_N\;g^{-1}$ biomass and 6.0 $10^{-3}\;g_P\;g^{-1}{_{biomass}}$, respectively. The possibility of using 100% (v/v) $CO_2$ gas as carbon source is also evaluated for the first time in the literature as far as N. eucaryotum is concerned. The strain showed a good adaptability to high concentrations of dissolved $CO_2$ as well as to low pH. The lipid content under 100% $CO_2$ is about 16.16 %wt $wt^{-1}$ and the fatty acid methyl esters composition of the extracted oil is in compliance with the European regulation for quality biodiesel.

• Steel and Composite Structures
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• 제22권1호
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• pp.141-159
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• 2016

Commonly in steel frames, steel beam and concrete slab are connected together by shear keys to work as a unit member which is called composite beam. When a composite beam is subjected to positive bending, flexural strength and stiffness of the beam can be increased due to "composite action". At the same time despite these advantages, composite action increases the strain at the beam bottom flange and it might affect beam plastic rotation capacity. This paper presents results of study on the rotation capacity of composite beam connected to Rectangular Hollow Section (RHS) column in the steel moment resisting frame buildings. Due to out-of-plane deformation of column flange, moment transfer efficiency of web connection is reduced and this results in reduction of beam plastic rotation capacity. In order to investigate the effects of width-to-thickness ratio (B/t) of RHS column on the rotation capacity of composite beam, cyclic loading tests were conducted on three full scale beam-to-column subassemblies. Detailed study on the different steel beam damages and concrete slab damages are presented. Experimental data showed the importance of this parameter of RHS column on the seismic behavior of composite beams. It is found that occurrence of severe concrete bearing crush at the face of RHS column of specimen with smaller width-to-thickness ratio resulted in considerable reduction on the rate of strain increase in the bottom flange. This behavior resulted in considerable improvement of rotation capacity of this specimen compared with composite and even bare steel beam connected to the RHS column with larger width-to-thickness ratio.