• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.186-192
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• 2007

In general, pulsation damper is installed in fuel rail for conventional MPI engine to decrease undesirable noise in vehicle cabin room. However, pulsation damper is so expensive that there are prevailing studies to reduce fuel pressure pulsations with integrated damping effect. This paper is one of basic studies for development of fuel rail to abate pulsations with self-damping effect. Primarily, the pressure pulsation characteristics was investigated with aspect ratio of cross section, wall thickness, and materials of fuel rail. A high aspect ratio or thin wall was found to absorb the pressure pulsations effectively. But volume effects on the fuel pressure pulsation reductions were not especially significant than cross section effects because volume increment rate is larger than pressure pulsation reduction rate. The fuel rail made of aluminum is effective for reduction of pressure pulsation than that of low-carbon steel. Pressure change period increases on the basis of same lengths of supply line and fuel rail as the volume is enlarged and/or the thickness of wall is thinned.

• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.199-209
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• 2004

The main purpose of this study is to explore a social capital paradigm which can be applied to many forms of social capital and intangible goods. The social capital paradigm introduces a new form of capital. This new form of capital produces a flow of socio-emotional goods that have value. Moreover, these socio-emotional goods can attach themselves to the objects used to convey them and change their value and meaning. This change in value and meaning is defined as attachment values. Exchanges of socio-emotional goods occur in networks where social capital resides. Formal and informal institutions provide order and meaning to exchanges of tangible and intangible goods. Social capital is a powerful resource that makes our choices interdependent. The social capital paradigm does not alter or contradict the basic economic theories of exchange. While the social capital paradigm accepts that selfish preferences motive many actions, it adds that sympathy and the desire to consume socio-emotional goods are powerful motivators. In case of marine affairs, ocean and fishing villages and their culture have been not only a fundamental basis of fisheries development but they also have made a great deal of contribution to forming social capital. In spite of this fact, the main reason that the problems of fisheries fishing villages fishermen in our society are kept at a distance is because they have been loosing their capability of forming social capital and producing socio-emotional goods, in addition to lowered relative economic share.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2905-2918
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• 2023

The valve assembly used in nuclear power plants is important safety-related equipment. In the new standard, the physical attributes are measured using a valve diagnosis test, which is used in the expansion to other non-tested valves using a quantitative test-basis methodology. With a motor-operated actuator, the state of stem's lubrication is related to physical attributes such as the stem factor and the friction coefficient. This study analyzed the numerical transient of fluid and solid lubrication with a squeeze film effect due to the loading rate on the stem and the stem nut using the experimental data. The differential equation that governs the motion mechanism of the stem and stem nut is established and analyzed. The flow rate, the fluid and the solid contact forces are calculated with the friction coefficient. Finally, we found that a change in the friction coefficient results from a change of the shear force in the solid contact mode during the interchange process between the solid contact mode and the fluid contact mode. The qualitative understanding of the squeeze film effect is expanded quantitatively for forces, thread surface distance, velocity, and acceleration, with consideration of the metal solid contact and fluid contact.

• Journal of the Korean housing association
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• v.27 no.1
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• pp.51-61
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• 2016

Under the guise of a residential environment improvement, distendedly designated Pre-Housing Renewal districts and Renewal Districts by Basic Plan for Renewal Projects are not promoted and leaved for a long-term so that residential problems have become worse. In case of the canceled Housing Renewal district, at the time when the district are canceled, the residential environment has become already superannuated for more than 10 years but there is no follow-up plan to manage that problem so that the exact management plan for those neglected districts is urgently needed. Therefore, the purpose of this study is to analyze the aspect of change of residential environment after the cancellation and indicate appearing problems by conducting on the case of Canceled districts of Daegu Housing Renewal District. This study will be the first step to seek practical management measures for canceled districts, and on the basis of this, the research will become a precedent to seek the sustainable planning measures for the designation and management of Renewal Projects from now on.

• The Korean Journal of Nuclear Medicine
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• v.8 no.1_2
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• pp.25-28
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• 1974

The concentrations of some blood constituents are known to be influenced by the postural change. The blood glucose and insulin concentrations were measured, first, in the supine, and then (30 minutes later) in the erect positions under the Lasting state. The effects of a duretic, furosemide, were also studied under the same condition for 5 consecutive days. The materials were 5 healthy volunteers aging 20-29 years old with out any diabetic past, or family histories. The blood glucose was measured by the Nelson's method, and plasma insulin by the radioimmunoassay method. Following are the results; 1. The plasma insulin concentration in the erect position is slightly higher than in the supine position, however, the increase is statistically insignificant because of the notable individual variations in the values of the supine position. 2. Four cut of 5 cases show the increase of about 80% of plasma insulin in the erect position, which is statistically significant if analyzed on the basis of frequency distribution. 3. The blood glucose concentration showed no postural changes. 4. The increase of the plasma insulin concentration in the erect position seems to be the result of limited extra vasation of insulin in the lower extremities.

• Journal of the Korea Computer Industry Society
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• v.5 no.1
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• pp.109-122
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• 2004

It is the emergence of multimedia based on information revolution that foretells and develops the largest change in the transfiguration of a modern design. In this paper, the basic principle and characteristics of a new design model is compared and analyzed, and the change of communication based on information form in order to examine the concept and characteristics of digital as today's new media in detail is considered in an changed environment. And also a new theoretical ground is derived about ‘virtual reality’ and ‘interaction’ which is the important characteristics of a digital media so as to compare the property of digital with that of analogue, analyze them and specify the concept and characteristics of digital. Thus the validity of this study is proved by a new interpretation methode of ‘spatiotemporal structure’ on the digital design on the basis of the above mentioned things

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.511-514
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• 2004

Proposed about new inverter that can use in PV system in this paper. Multi_level inverter that used inverter makes use of 4 transformers is basis, primary winding of each transformer voltage as can do step_up or step_down to appropriate voltage space tap lake. Put circuit that tap that turn in transformer connects properly according to inhibit signal that sense change of input voltage (output voltage of solar cell place) and transformer secondary voltage controls point of contact of relay so that get into fixed output voltage. As a result, can minimise relative harmonic content despite change width of input voltage are wide because number of output voltage level of multi_level inverter does not decrease. Because proposed circuit manufactures is easy and control is easy and is no burden of cost price rise economically, commercialization expected to do easily and this study examined propriety of action as that compose and experiments proposed circuit.

• Journal of the Korea Fashion and Costume Design Association
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• v.15 no.2
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• pp.57-64
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• 2013

As the clothing materials have been more functional and advanced, the cotton fabrics for dress shirts or blouses have been more qualified and the sewability for high degree of completion has been required. This study aims to identify the seam strength depending on the change of stitch density of fine cotton fabrics by fabric and thread and so the general seam performance of fine cotton fabrics by analyzing the seam efficiency and breaking mode of seams. For an experiment, 3 kinds of fine cotton fabrics and 2 kinds of threads were selected and the sample was made by changing the stitch density by four steps. Then, the seam strength was measured. Next, the seam efficiency and breaking mode of seams were analyzed on the basis of the results of seam strength measurement. The results are as follows: All fabrics showed the similar tendency in seam strength. The seam strength is related to the tensile strength and thread strength, it increased only to a certain stitch density. When the stitch density exceeded a certain level, fabrics were destroyed or threads were cut. Then, the seam strength didn't increase. Furthermore, the more the seam strength increased, the more the seam efficiency increased. For increasing the maximum stitch density, it was required to use the fabrics and threads which had similar properties, in other words, the high thread strength for the high tensile strength and the low thread strength for the high tensile strength.

• Korean Journal of Environment and Ecology
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• v.16 no.3
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• pp.249-260
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• 2002

The cultivated lands in metropolitan, such as Seoul, are quasi-natural areas that have been disturbed continuously by human being and is in needs to be preserved and to be managed than to get more crop production in the light of nature experience for civilians through conservation of biodiversity and landscape diversity. However, the cultivated lands in urban areas have decreased rapidly, being changed into developmental areas in its land use. This study is to review change of land use as time change of the cultivated lands in Seoul and to draw the landscape ecological characteristics and structure in the cultivated land after their analysis on the basis of biotope type map in Seoul. The ultimate goal of this study is for development of prototype to enhance biodiversity in urban drypaddy culture area on the results of these analyses.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.4
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• pp.2094-2112
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• 2019

Focusing on the issue that the conventional Kernel Correlation Filter (KCF) algorithm has poor performance in handling scale change and obscured objects, this paper proposes an anti-occlusion and scale adaptive tracking algorithm in the basis of KCF. The average Peak-to Correlation Energy and the peak value of correlation filtering response are used as the confidence indexes to determine whether the target is obscured. In the case of non-occlusion, we modify the searching scheme of the KCF. Instead of searching for a target with a fixed sample size, we search for the target area with multiple scales and then resize it into the sample size to compare with the learnt model. The scale factor with the maximum filter response is the best target scaling and is updated as the optimal scale for the following tracking. Once occlusion is detected, the model updating and scale updating are stopped. Experiments have been conducted on the OTB benchmark video sequences for compassion with other state-of-the-art tracking methods. The results demonstrate the proposed method can effectively improve the tracking success rate and the accuracy in the cases of scale change and occlusion, and meanwhile ensure a real-time performance.