• Journal of the Korean Society of Safety
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• v.32 no.6
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• pp.61-67
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• 2017

Suspended sediment transport plays principal roles in morphological process of natural coastals. It is needed to understand the reason why interaction characteristics of solitary wave and suspended sediment. The present study shows that suspended sediment pickup derived on solitary wave celerity. The 2D prismatic open channel length is 12 m, width is 0.8 m, height is 0.75 m and slope is 1/6. Generation of solitary wave is used by rapidly opening the sluice gate. Bottom surface sediments are laid movable slope section by 0.03 m thickness and experimental sediments are used anathracite and jumoonjin sand. Techniques of suspended sediment pickup rate are designed equipment ASC(Absorptive Suspended sediment Collector). It could directly absorb 5 points suspended sediment by channel water depth. Solitary wave celerity is measued by ADV(Acoustic Doppler Velocimeter). Mounted two video cameras(Model No. : Sony, HDR-XR550) are used to image processing of suspended sediment concentration and turbidity. Suspended sediment pikcup rate(Einstein, 1950) is analyzed to nondimensionalization based on solitary wave celerity. The suspended sediment pickup rate is suggested that more effective plunging breaking type than spilling. The results indicates fundamental suspended sediment transport mechanism between solitary wave celerity and suspended sediment pickup based on laboratory experiments. Finally, the present study suggests that suspended sediment pickup rate by solitary wave is used only characteristics of sediment and solitary wave celerity.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.81-82
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• 2006

• Journal of the Economic Geographical Society of Korea
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• v.14 no.2
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• pp.116-128
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• 2011

Some subway passengers may want to have their fresh vegetables purchased through internet at a service facility within the subway station of the Metropolitan Seoul subway system on the way to home, which raises further questions about which stations are chosen to locate service facilities and how many passengers can use the facilities. This problem is well known as the pickup problem, and it can be solved on a traffic network with traffic flows which should be identified from origin stations to destination stations. Since flows of the subway passengers can be found from the smart card transaction database of the Metropolitan Seoul smart card system, the pickup problem in the Metropolitan Seoul subway system is to select subway stations for the service facilities such that captured passenger flows are maximized. In this paper, we have formulated a model of the pickup problem on the Metropolitan Seoul subway system with subway passenger flows, and have proposed a fast heuristic algorithm to select pickup stations which can capture the most passenger flows in each step from an origin-destination matrix which represents the passenger flows. We have applied the heuristic algorithm to select the pickup stations from a large volume of traffic network, the Metropolitan Seoul subway system, with about 400 subway stations and five millions passenger transactions daily. We have obtained not only the experimental results in fast response time, but also displayed the top 10 pickup stations in a subway guide map. In addition, we have shown that the resulting solution is nearly optimal by a few more supplementary experiments.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.5
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• pp.234-241
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• 2002

An optical pickup actuator is an objective-lens-moving mechanism that provides a means to follow the disk displacement accurately(1). In this paper, a slim type optical pickup actuator for Notebook PCs is analyzed and designed to improve the driving sensitivity A three dimensional equivalent magnetic circuit network method (3D-EMCN method) is proposed for an analysis method which provides better characteristics in both precision and computation time of analysis comparing with a commercial three-dimensional finite element (3D-FEM) codes. To verify the validity of proposed method, we made a comparison between the analysis results and the experimental ones. We also compared this analysis results with 3D-FEM results. Among the several optimal algorithm, we adopt a niching genetic algorithm, which renders a set of the multiple optimal solutions. RCS (Restricted Competition Selection) niching genetic algorithm is used for optimal design of the actuator's performance. Recently, the pickup actuator needs additional driving structure for radial and tangential tilting motion to obtain better pick-up performance. So we applied the proposed method to the model containing tilting coils.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.7
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• pp.1598-1603
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• 2011

This paper describes an enhancement method for a computational pickup model. The conventional computational pickup model utilizes the ray-trace model and the pinhole model. The conventional model is very useful, however, it suffers from quality degradation of reconstructed images at long distances. To overcome the problem, we propose an accurate pickup model. The proposed model includes integration of the rays incoming to a sensor that generates a pixel, resulting in robustness on the Aliasing artifact. To show the effectiveness of the proposed method, experimental results are carried out. The results indicated that the proposed method is superior to the conventional method.

• Progress in Superconductivity
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• v.5 no.1
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• pp.45-49
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• 2003

We have designed and fabricated the single-layer high $T_{c}$ SQUID magnetometer consisting of a directly coupled grain boundary junction SQUID with an inductance of 100 pH and 16 nested parallel pickup coils with the outermost dimension of 8.8 mm ${\times}$ 8.8 mm. The magnetometer was formed from a YBCO thin film deposited on an STO(100) bicrystal substrate with a misorientation angle of $30^{\circ}$. The SQUID magnetometer was further improved by optimizing the multi-loop pickup coil design for use in unshielded environments. Typical characteristics of the dc SQUID magnetometer had a modulation voltage of 40 $\mu\textrm{V}$ and a white noise of $30fT/Hz^{1}$2/. The SQUID magnetometer exhibited a 1/f noise level at 10 Hz reduced by a factor of about 3 compared with that of the conventional solid type pickup coil magnetometers and a very stable flux locked loop operation in magnetically disturbed environments.s.

• Korean Journal of Optics and Photonics
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• v.16 no.4
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• pp.345-353
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• 2005

We proposed a new and cost-effective method fer assembling holographic pickup modules without any high resolution vision system. Assembling was accomplished by adjusting photodiode package only, leading to a low cost, holographic pickup module. Focus and tracking error signals were simply determined by comparing spot sizes and by using the 3 beam method, respectively, based on four-sectional holographic optical elements. In experiment, we assembled a hologram module and estimated performance of the proposed method fur a holographic pickup module used in compact disc system.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.2
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• pp.366-373
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• 2007

In this paper we propose a multi-channel speech pickup system for calling quality enhancement of hands-free communication using ALTERA Nios-II processor. Multi-channel speech pickup system uses Delay-and-Sum beamformer with zero-padding interpolator. This paper implements speech pickup system using the Nios-II processor with real-time I/O data processing speed. The proposes speech pickup embedded system shows a good agreement with those of computer simulation(MATLAB) and conventional DSP processor(TMS320C6711) result. The proposed method is effective more than previous methods in cost and design processing time. As a result, LE(Logic Element) of hardware used 3,649/5,980(61%) on a chip.

• Journal of Distribution Science
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• v.19 no.10
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• pp.5-15
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• 2021

Purpose: This study aims to present individual motivation and channel characteristics affecting omnichannel service use, as well as the effect relationship of the brand factor on consumption value, service satisfaction, and continuous usability based on convenience store pickup service, one of online shopping customers' omnichannel use services. Primarily, this study divided consumption value into emotional value and functional value and examined the consumption value characteristics of omnichannel-based pickup service customers. Research design, data and methodology: A questionnaire survey was carried out targeting 324 consumers having the omnichannel-based pickup service user experience in online shopping in Korea. A confirmatory factor analysis and path analysis were carried out based on the structural equation to verify hypotheses. Results: According to the analysis result, individual motivation affected the emotional value, and the omnichannel characteristics affected functional value. The brand effect influenced both emotional and functional values. The emotional value affected continuous use intention, and the functional value affected service satisfaction. Conclusions: Therefore, consumers' emotional and functional values showed differences in consumption behavior. In online shopping companies' marketing strategy construction for omnichannel, it was confirmed that a differentiated approach is needed depending on the strategic goal of satisfaction improvement and continuous use intention consolidation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.635-639
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• 1997

In order to design a system a process or plant must be put into a mathematical form for analysis and evaluation, and an appropriate controller must be designed to attain the desired system response. In this paper, the mathematical model for an optical pickup actuator is proposed and an H .inf. controller is employed to obtain the optimal focusing/tracking servo system behavior. Simulation and experiments are carried out to verify the performance of the proposed model.