• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2489-2494
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• 2008

The two-dimensional circular cylinder freely falling in a channel has been simulated by using Immersed boundary - lattice Boltzmann method in order to analyze the characteristics of motion originated by the interaction between the fluid and the solid. The wide range of the solid/fluid density ratio has been considered to identify the effect of the solid/fluid density ratio on the motion characteristics such as the falling time, the terminal velocity and the trajectory in the vertical and horizontal directions. In addition, the effect of the gap between the cylinder and the wall on the motion of two-dimensional circular cylinder freely falling has been revealed by taking into account a various range of the gap size. The Reynolds number in terms of the terminal velocity is diminished as the cylinder becomes close to the wall at the initial dropping position, since the repulsive force induced between the cylinder and wall constrains the vertical motion. Quantitative information about the flow variables such as the pressure coefficient and vorticity on the cylinders is highlighted.

• Journal of Information Processing Systems
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• 제18권2호
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• pp.208-222
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• 2022

Through the analysis of the coordination mechanism of the supply chain system of China's automobile manufacturing industry, the factors affecting the supply subsystem, the manufacturing subsystem, the sales subsystem, and the consumption subsystem are sorted out, the supply chain coordination index system based on the influence factor of four subsystems is established. The evaluation models of the coordination degree in the subsystem of the supply chain, the coordination degree among the subsystems, and the comprehensive coordination degree are established by using the efficiency coefficient method and the collaborative entropy method. Experimental results verify the accuracy of the evaluation model using the empirical analysis of the collaborative evaluation index data of China's automobile manufacturing industry from 2000 to 2019. The supply chain synergy of automobile manufacturing industry was low from 2001 to 2005, and it increased to a certain extent from 2006 to 2008 with a small growth rate from 0.10 to 0.15. From 2009 to 2013, the supply chain synergy of automobile manufacturing industry increased rapidly from 0.24 to 0.49, and it also increased rapidly but fluctuated from 2014 to 2019, first rising from 0.68 to 0.84 then dropping to 0.71. These results provide reference for the development of China's automobile manufacturing supply chain system and scientific decision-making basis for the formulation of relevant policies of the automobile manufacturing industry.

• The Plant Pathology Journal
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• 제39권2호
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• pp.228-233
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• 2023

Two pear cultivars with different degrees of resistance to Venturia nashicola were evaluated on the basis of a disease severity rating for pear scab resistance under controlled environmental condition. Two inoculation techniques were tested: the procedure for inoculation by dropping conidia suspension of V. nashicola; the procedure by deposition of agar plug on the abaxial surface of pear leaves. All tested cultivars resulted in blight symptoms on the inoculated leaves and became spread to uninoculated region or other leaves. Although both methods provide satisfactory infection of V. nashicola on pear leaves, the mycelial plug method of inoculation was more reliable than the spray inoculation method for the evaluation of pear scab disease resistance. The incubation period of V. nashicola in the resistant pear cultivar, Greensis was longer than that in the susceptible cultivar, Hwasan.

• 한국멀티미디어학회논문지
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• 제17권9호
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• pp.1115-1124
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• 2014

The objective of this study is to present a new design method at the idea brainstorming process, which requires a great deal of time and effort to seek their own ideas in existing design process and to develop a user support idea forms generation system called OCIGS (Openware Creative Idea Generation System) that makes it possible to create a variety and 3D forms as well as a quantitative evaluation data for the actual types that compose the aesthetic factors and designs of qualitative standards. In order to achieve these objectives : First, overcoming the limitation of 3D form generation ability by establishing visual application system, Second, accepting users' opinions by generating 3D images dynamically, analysing and giving information on the preferred ones on the web on real time, Third, identifying tendency of preference so that they can generate preferred colors and images in future by updating image combination and dropping low-preferred ones. This system would play a role as an idea or form generation application in the actual 3d form design development process.

• 한국정밀공학회지
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• 제23권3호
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• pp.132-138
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• 2006

With a great requirement of innovation caused by severe competition current companies are encouraged to improve bottleneck areas in production procedure. Specially a chassis line in which assembly processes are mainly carried out manually has the large potential to be automated. The putting of spare tire in trunk in chassis line is still dominated by free dropping method. Through that, parts in trunk such as luggage room lamp, jack and so on were damaged and the complaint of assembler in the next process was occurred due to physical strength. To eliminate these, tile robot system was in this paper developed to place spare tire on the mounting hole in trunk. The movement of robot was synchronized with the velocity of chassis hanger. With this automated system the productivity of the chassis line was increased from the benefits such as simplification of the system using only robot without the mechanically synchronized transport, inserting spare tire into the right position with robot, reduction of damaged parts and production of various type of car.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.501-504
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• 2004

This paper describes the fabrication method for atomic force microscopy(AFM) tip with multi-walled carbon nanotube(MWNT). For making a carbon nanotube (CNT) modified tips, AC electric field which cause the dielectrophoresis was used for alignment and deposition of CNTs in this research. By dropping the MWNT solution and applying an electric field between an AFM tip and an electrode, MWNTs which were dispersed into a diluted solution were directly assembled onto the apex of the AFM tips due to the attraction by the dielectrophoretic force. In this case, we investigate the effect of the angle between a tip axis and an electrode. Experimental setup were presented, and then CNT attached AFM tips are successfully shown in this paper.

• International Journal of Automotive Technology
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• 제8권3호
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• pp.327-335
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• 2007

A new optimization scheme and some key techniques are proposed in the development of a vehicle glass drop design software system. The key issues of the design system are how to regenerate the glass surface and make the vehicle glass drop down along the glass channels. To resolve these issues, a parameterized model was created at first, in which the optimizing method and Knowledge Fusion techniques were adopted the optimized process was then written into the glass drop design system by coding with C language and UGS/Open Application Programme Interface functions etc. Therefore, the designer or engineer can simulate the process of glass dropping along the channels to assess the potential interference between glass and door accessory by using this software system. All of the testing results demonstrate the validity of the optimizing scheme, and the parametric design software effectively solves the key issues on development of the door accessory package.

• 한방안이비인후피부과학회지
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• 제19권2호
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• pp.19-25
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• 2006

Objective : This experimental study was performed to investigate the effect of Soyum Herbal-acupuncture, Hwangryunhaedoktang & Coptidis rhizoma on Staphylococcus epidermidis that induce keratitis. Methods : MIC was measured by dropping to $50{\mu}l$ according to density Soyum Herbal-acupuncture, Hwangryunhaedoktang & Coptidis rhizoma(100%, 10%, 1%, 0.1%). Anti-bacterial potency was measured by the size of inhibition zone with change of volume. Results : 1. MIC on Staphylococcus epidermidis in Soyum Herbal-acupuncture dippear all sample. 2. MIC on Staphylococcus epidermidis in Hwangryunhaedoktang disappear all sample. 3. MIC on Staphylococcus epidermidis in Coptidis rhizoma was 100%, $50{\mu}l$ and anti-bacterial potency increase compare with quantity. Conclusions : The present author think that Soyum Herbal-acupuncture must be extracted a new method for anti-bacterial potency and Coptidis rhizoma was made Herbal-acupuncture for eye drops.

• 산업기술연구
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• 제22권B호
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• pp.175-184
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• 2002

In this paper, we proposed separate queue scheme in each hierarchical cell for effective use of wireless channel. This method reduces the blocking rata of high speed mobile station's handoff in hierarchical cellular systems. Basically for the high speed mobile stations channels are allocated in macrocell and for the low speed mobile stations channels are allocated in microcell. In order to reduce the rate of forced handoff termination, some reservation channels are employed for the fast handoff calls in the macrocells. And the queue is located in each cell to be able to store handoff requests and takeback requests. The overflowed mobile station are able to perform takeback as soon as a corresponding channel is available.

• Journal of information and communication convergence engineering
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• 제6권1호
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• pp.19-23
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• 2008

The AQM (Active Queue Management) starts dropping packets earlier to notify traffic sources about the incipient stage of congestion. The AQM improves fairness between response flow (like TCP) and non-response flow (like UDP), and it can provide high throughput and link efficiency. In this paper, we suggest the QVARED (Queue Variation Adaptive RED) algorithm to respond to bursty traffic more actively. It is possible to provide more smoothness of average queue length and the maximum packet drop probability compared to RED and ARED (Adaptive RED). Therefore, it is highly adaptable to new congestion condition. Our simulation results show that the drop rate of QVARED is decreased by 80% and 40% compare to those of RED and ARED, respectively. This results in shorter end-to-end delay by decreasing the number of retransmitted packets. Also, the QVARED reduces a bias effect over 18% than that of drop-tail method; therefore packets are transmitted stably in the bursty traffic condition.