• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.1
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• pp.186-193
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• 2009

In this paper, we adopted E-MOLD patent technology in order to fabricate Prismless LGP(Light Guide Panel) fur cellular phone and estimate the transcription of injection-molded parts. Then, we manufactured the Ni stamper fur Prismless LGP using MEMS process. And the stamper was installed in the movable heated core which is the key part of a patented mold. Using this mold, we manufactured injection-molded plastic LGP parts with different mold temperatures so that we investigate effect of the temperature on the transcription of the parts. The CAE analysis was also conducted in order to compare with the experimental results. The transcription of LGP parts with various mold temperature displayed $100^{\circ}C$(25.0nm), $140^{\circ}C$(48.4nm), $180^{\circ}C$(52.1nm) and when compared with stamper(521Inm), transcription was superior at $180^{\circ}C$. According to the CAE results, moldability was improved as mold temperature ($50^{\circ}C{\sim}180^{\circ}C$) increased, but when filling time($1{\sim}2sec$) increases, it decreased at $160^{\circ}C$. And transcription and moldability were improved markedly at glass transition temperature($140^{\circ}C$).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.7
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• pp.687-692
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• 2015

A mold design for in-mold coating was developed to achieve simultaneous coating and injection molding of an automotive armrest. The developed mold includes one core and two cavities which are composed of a substrate cavity and a coating cavity. The core was attached to a movable plate and two cavities were mounted on a plate sliding in a stationary plate. In a two-step process, the part was first injection molded and subsequently, with the aid of a sliding table, was transferred to a second cavity. The materials used were PC/ABS for substrate and two-component polyurethane for coating. The experiments were conducted by changing the flow rate to investigate mixing characteristics. As the flow rate increased, the mixing improved. Additionally, the bubbles appeared over the substrate surface decreased with an increase of the weight of injected coating material.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.965-975
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• 2004

The writer reviewed on Chojop and came to conclusions as follows. Symptoms of Chojop is appeared digestive ailment such as belching, nausea, regurgitation of acid, stomachache etc., if being serious, felt oppressed with palpitating in chest and uneasiness at times. In Dangaesimbub written by Chujinhyung, the causes of Chojop were mainly regarded as phlegmatic fire(痰火) and suggested the way of treatment. The causes of Chojop are movable fire with phlegm, insufficiency of blood caused by thinking to excess, and Shinyanghohan(腎陽虛汗) that is piled cold phlegm by voidance and coldness of Renal Yang, but the main cause is brought to a conclusion as phlegmatic fire. The phlegmatic fire is come from being in discord with the spleen and the stomach, or from in harmony between vigor and blood according to essence and vital energy which are disturbed by combined feelings. That is caused by disharmony between inner and outer conditions according to individuals. The distinctive features in shapes of Chojop are revealed to shapes such as manlike woman, womanlike man, wearing darkish or reddish color between two eyebrows, being almond eyed, strong eyebrows, being sunk the upper part of the nose bridge, lots of facial blots, Dam-body, Ki type, Shin type, Birds group, and Yangmyung type. The doctors can prescribe Whadamchungwhatang to Yangmyung type, Yanghyulsamul-tang for patients with strong eyebrows so flourishing blood and vigor, Hyangsapyungwuisan for patients belong to Birds group, Soshikchungul-tang for Ki type, and Palmiwhan for man belonged to Bangkwang-body with voidance and coldness of Renal Yang chiefly.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.12
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• pp.1308-1315
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• 2009

A full-polarimetric scatterometer(HPS: Hongik Polarimetric Scatterometer) for X-band is designed, fabricated, and verified using the theoretically well-known point-targets in this paper. The X-band full-polarimetric scatterometer consists of an OMT(Orthogonal-Mode Transducer)+horn antenna, the angle control part for the OMT+horn antenna, a transmitter/receiver with a network analyzer and a frequency-conversion circuitry, and a movable support of these parts. We use an inclinometer sensor to control the vertical and horizontal incidence angles. The full polarimetric data can be obtained because of the polarization switches and the OMT. The accuracy of the scatterometer system is verified by measuring the polarimetric RCS(Radar Cross Section) of one of the theoretically well-known point-targets, i.e., a corner reflector.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.1
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• pp.108-117
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• 2011

Old train carriages have been used to create artificial reefs (AR) as part of programs to enhance ocean fisheries and recreational resources. This study conducted hydraulic modeling experiments to estimate the structural stability of a train carriage AR. By applying fixed- and movable-bed conditions and Froude similitude, theoretical and hydraulic experiments revealed major design forces(e.g., water waves and currents). The results of this study showed that some dimensionless design parameters (e.g., surf similarity parameters, water particle velocity, scouring, and deposition) also affect the stability of an AR under various wave and current field conditions. In the fixed-bed condition, movement of the AR occurred when dimensionless water particle velocity based on the surf similarity parameter was larger than about 0.32. In the moveable-bed condition, the settlement depth (field values) of the AR ranged from 6 to 30 cm. The results indicated that characteristics of the sediment/bed condition and the direction of external forces acting on an AR should be considered when selecting AR sites.

• The Journal of the Korea Contents Association
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• v.8 no.6
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• pp.8-15
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• 2008

In this paper, in order to analyze property of frequency response in optical microphone, system was implemented. The capacitance microphone and fiber-optic transmission path type fiber-optic microphone (FOM) have weaknesses in directivity, size, weight, and price. However suggested optical microphone can be constituted by cheap devices, so it has many benefits like small size, light weight, high directivity, etc. Head part of optical microphone which is suggested in this paper is movable back and forth by sound pressure with the attached reflection plate. Operating point is determined by measuring the respond characteristics and choosing the point on which has maximum linearity and sensitivity while changing the distance between optical head and vibrating plate. We measured the output of the O/E transformed signal of the optical microphone while frequency of sound signal is changed using sound measurement/analysis program, Smaart Live and USBPre, which are based on PC, and compared the result from an existing capacitance microphone. The measured Optical microphone showed almost similar output characteristics as those of the compared condenser microphone, and its bandwidth performance was about 300[Hz]-3[kHz] at up to 3 [dB].

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.709-715
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• 2011

Chattering in cutting operations are usually a cumbersome part of the manufacturing process in mechanical. Particular, machining performance such as that of the boring process is limited by cutting condition at the movable components. Among various sources of chatter vibration, detrimental point in cutting condition is found a mechanical condition on overhang. It limits cutting speed, depth, surface roughness and tool wear failure as result because the all properties are varying with the metal removal process. In this case, we have to observe the resonance frequencies of a boring bar for continuous cutting. In the established research, boring bar vibration of cutting system has been measured with the aid of accelerometer. However, the inherent parameters of internal turning operations are severely limit for the real time monitoring on accelerometers. At this point, this paper is proposed other method for real time monitoring during continuous cutting with optical fiber at the inside of boring bar. This method has been used a plastic fiber in the special jig on boring bar by based on experimental modal analysis. In this study, improvement of monitoring system on continuous internal cutting was attempted using optical fiber sensor of inside type because usually chattering is investigated experimentally measuring the variation in chip thickness. It is demonstrated that the optical fiber sensor is possibility to measure of chattering with real time in boring process.

• The KIPS Transactions:PartC
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• v.15C no.4
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• pp.311-320
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• 2008

In general, routing algorithms that were applied to ad-hoc networks are not suitable for the environment with many nodes over several thousands. To solve this problem, hierarchical management to these nodes and clustering-based protocols for the stable maintenance of topology are used. In this paper, we propose the clustering-based modified LEACH protocol that can applied to an environment which moves around metal containers within communication nodes. In proposed protocol, we implemented a module for detecting the movement of nodes on the clustering-based LEACH protocol and improved the defect of LEACH in an environment with movable nodes. And we showed the possibility of the effective communication by adjusting the configuration method of multi-hop. We also compared the proposed protocol with LEACH in four points of view, which are a gradual network composition time, a reconfiguration time of a topology, a success ratio of communication on an containers environment, and routing overheads. And to conclude, we verified that the proposed protocol is better than original LEACH protocol in the metal containers environment within communication of nodes.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.6
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• pp.6-11
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• 2010

Amount of power generated from solar photovoltaic can vary according to solar flux of sunlight due to nature of solar cell panel, and an angle that the sun and the surface of cell makes brings difference in amount of power generation. Solar flux is decided by location of surface of the Earth that is classified into longitude and latitude, but on the other hand, an angle that the sung and the surface of cell makes can be changed by changing the angle of a solar power generation device at the fixed location. A method of changing the angle of a solar power generation device as a measure for improving practical power generation efficiency. and studies about a solar tracking device for this are in active. This study conducted a research on a solar tracking system for improvement of solar power generation efficiency. A solar tracking system of this study is composed of a sensor part to confirm a location of the sun with a semiconductor photosensor using the photo conductive effect, and it analyzed output signal of a sensor by using microprocessor and it produced a control signal of driving part for tracking the sun. A solar power generator (25W) was produced to analyze performance of a solar tracking system and usefulness of a solar tracking device that was designed and produced in this study was confirmed through experiments.

• The KIPS Transactions:PartB
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• v.10B no.2
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• pp.151-156
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• 2003

The vergence control method is presented for a parallel-axls stereo camera (PASC) using a signal processing technique such as shift, (rotation), and scaling. The PASC is considered as the simplest one of binocular stereo cameras. However, its major limitation lies in the controllability of vergence since its left and right imaging sensors of CCDs are fixed. On the other hand, a horizontal-moving-axis stereo camera (HMASC) with movable imaging sensors is able to control the vergence by moving its CCDs horizontally. In spite of its vergence controllability, there is a major drawback in the implementation because of complicated mechanical structure and the additional cost. To overcome the vergence control problem of the PASC, an operational principle of the HMASC is applied to the PASC. To be specific, without any additional hardware the vergence control problem of the PASC is solved with the signal processing technique. Assuming the virtual displacement between CCD's, a disappearing part of acquired images is removed and the original image site is recovered via interpolation. Experimental results show that the vergence control between stereo images captured by the PASC it possible with an acceptable degradation of the image quality defending on the virtual displacement of CCDs.