• Transactions of Materials Processing
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• v.16 no.1 s.91
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• pp.25-30
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• 2007

The present study covers an integrated simulation method to evaluate optical performance of an aspheric plastic lens by connecting a finite element (FE) analysis of injection molding with a ray tracing simulation. Traditional ray tracing methods have based on the assumption that the optical properties of a lens are homogeneous throughout the entire volume. This assumption is to a certain extent unrealistic for injection-molded plastic lenses because material properties vary at every point due to the injection molding effects. To take into account the effects of the inhomogeneous optical properties of the molded lens, a new.ay tracing scheme is proposed in conjunction with a FE analysis of the injection molding. A numerical scheme is developed to calculate ray paths on every element layer with more realistic information of the refractive indices which can be obtained through the FE analysis. This information is then used to calculate the ray paths based on the FE mesh of which nodal points have unique index values. The proposed tracing scheme is implemented on the tracing of an aspheric lens, and its validity is ascertained through experimental verification.

• Journal of Korea Multimedia Society
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• v.18 no.12
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• pp.1492-1500
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• 2015

In recent crime scene, there is the captured crime scene video at least one. So video files recorded on storage media often provide important evidence. Criminals often attempt to destroy storage saved crime scene video. For this reason recovery of a damaged or deleted video file is important to resolve criminal cases in aspects of digital forensic. In the recent, there is a study to recover video file based on video frames, but it is very poor time efficiency when the connecting video frames. This paper proposed advanced frame-based recovery technique of a damaged video files using time information. We suggest a new connecting algorithm to connect video frames using recorded time information in front of video frame. We also evaluate performance in aspects of time and experiment result shows that proposed method improves performance.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.1-9
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• 2008

It is restricted on CPU ability, memory, display size and networking to process GIS data on ubiquitous-based terminal. For that reason, we tried to improve the cadastral electronic file to solve these problems in this paper. The format of old cadastral electronic files is not efficient because it is made of file structure. So, it has inconvenience to let us read whole file, displaying on the screen and connecting to geographic objects by adding index file like database for connecting to geographic object and displaying on the screen. The file size was decreased to 27.6% of original file size through converting format.

• 한국기계연구소 소보
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• s.16
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• pp.127-136
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• 1986

Recently deck crane of multi purpose cargo vessel (MPCV) is designed to posi¬tion in side instead of in the center line of the upper deck with a view to reduce the transportation cost and shipbuilding cost by shortening the length of ship. In this paper, the crane post was at first designed according to the crane maker’s specification and parent ship and the structure is analysed with Finite Ele¬ment Method. Through the careful reviews on the result of analysis, the final design of crane post was modified. The crane post is designed as a cylindrical in upper part and hexagonal in lower part instead of cylindrical on the whole as before. The connecting part of crane post is designed with the form of mixture of the cylinderical and hexagonal. Since the center of cylindrical and hexagonal section are not on the same line, it is expected to have the stress concentration. So, in order to attenuate the concentrated stress on the connecting part, the upper and lower parts was stiffened by inserting plate to enlarge the area of welding. The structure of deck part includes the tank side floor which is depend on the lower structure of the crane post that would support the force of the crane post by placing with 1.5 frame interval of the vertical plate.

• Journal of Biosystems Engineering
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• v.26 no.5
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• pp.415-422
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• 2001

A seedling pick-up device for vegetable transplanters was developed and its work performance was evaluated at the laboratory. The pick-up device extracts seedlings from a 200-cell tray of seedlings and transfers them to the place where they are to be transplanted into the soil. The device consists of a path generator, pick-up pins and a pin driver. The path generator is a five-bar mechanism comprised of a fixed link, a driving link, a driven link, a connecting link and a slider. The slider is constrained to move along the driven link and a fixed slot of combined straight-line and circular paths. The connecting link joins the driving link and the slider. When the slider moves along the straight-line path of the slot it takes seedlings out from the cell and transfers them to the transplanting hopper when moving along the circular path. A proto-type of the pick-up device was built and tested under the various operational conditions such as age of seedling, approach direction and penetration depth of pins to the cell, holding method of seedling and extracting velocity. The device extracted 30 seedlings per minute with the maximum success ratio of 97% using the seedlings of 23 days old. Some design details were also discussed and suggested to enhance the performance of the device.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05b
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• pp.133-136
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• 2011

This study concerned with the steel beam of bonding method and bonded steel beams by this method and both ends of different height, steel beams and steel beams in the center makes the junction. Both ends and the central part of steel beams connecting the lower flange by additional combining steel plates to convey stress, the stress to focus on the beam connections are passed to both ends of steel beams, and strength of beam connections is improved and steel structural beams is proposed to minimize the loss by Incision. If you use the developed method, the construction period is shortened, and reducing the amount of material can decrease the cost and reduction in floor height can be maximized business feasibility.

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2816-2822
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• 1999

In this paper, a fast thinning method for fingerprint image by separating end and bifurcation region is proposed. To detect feature points in automatic fingerprint identification system, thinning of fingerprint is essential. The end and bifurcation regions in ridge line are separated by means of run-length coding, and parallel thinning method is applied to the separated regions. The rest parts except the end and bifurcation regions are processed by connecting center points of each run. The performance of the proposed method has been evaluated by CPU processing time and thinness measurement. By the experimental results, the proposed method is fast and has high thinness value.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.179-179
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• 2021

Top-Down construction method is a method of connecting a beam to a column and using a strut to support earth retaining walls. This method has the advantage of reducing the process of underground construction by reducing the work of installation. Recently, there are a lot of cases of damage and defect occurring in H-beam backfill applied to Top-Down construction method and the concrete slab supporting H-beam backfill. For this, appropriate methods were suggested through finite element analysis of the position and installation form of the H-beam backfill.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.299-302
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• 2000

In this paper, a Inter-Working Function Unit(IWF) has been developed and designed in order to change to advanced subscriber system the Remote Subscriber System(RSS) that is operating with simple services(PSTN Function only). Regarding the cost and the effectiveness, RSS should be connected to Access Subscriber System with PCM cables directly. As this method being used, in the period of Retrofit, the connecting job covering RSS will be handled easily and safely.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2000.11b
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• pp.173-178
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• 2000

As a way of decreasing trial and error that can occur in design, we investigated many kinds of material information and image information. We apprehended structures of material database and image database to suggest one of design method that provides information by connecting both databases. This has potentiality to improve the quality of design. Ultimately, this potentiality makes a great contribution towards strengthening competitiveness in design.