• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.9C
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• pp.871-878
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• 2002

The cartesian loop chip which is one of key devices in narrow-band Walky-Talky transmitter using RZ-SSB modulation method was designed and implemented with 0.35 ㎛ CMOS technology. The reduced size and low cost of transmitter were available by the use of direct-conversion and cartesian loop chip, which improved the power efficiency and linearity of transmitter. In addition, low power operation was possible through CMOS technology. The performance test results of transmitter showed -23㏈c improvement of IMD and -30㏈c below suppression of SSB characteristic in the operation of cartesian loop chip (closed-loop). At that time, the transmitting power was about 37㏈m (5W). The main parameters to improve the transmitting characteristic and to compensate the distortion in feed back loop such as DC-offset, loop gain and phase value are interfaced with notebook PC to be controlled with S/W.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.8
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• pp.781-787
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• 2004

In this paper, a novel dual and wide band aperture stacked patch antenna for Cellular/PCS/IMT-2000 base station is presented. It consists of single microstrip patch having notches along the radiating patch, two dielectric substrates and a form material. To achieve wide band characteristic, we utilize the coupling effect between the notched patch and the resonant aperture in the ground plane and by properly cutting notches on the patch, an aperture stacked patch antenna could be designed to yield dual frequency operation. By the proper choice of resonant aperture size and height of a foam material, dual and wide band characteristic could be realized the measured impedance bandwidth(1:1.5 VSWR) of designed antenna at lower band(860 MHz) reaches 77 MHz and covers the Cellular CDMA band(824∼894 MHz). The measured impedance bandwidth(1:1.5 VSMR) of the designed antenna at upper band(1,960 MHz) is about 550 MHz and covers both the PCS band(1,750∼l,870 MHz) and the for-2000 band(1,920∼2,170 MHz). Good broadside radiation with high gain(5.65∼7.4 dBi) characteristics have also been observed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.5 s.108
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• pp.401-407
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• 2006

In this paper, we present a small-sized and light weighted dual-band antenna for an access point of 2.4/5 GHz dual-band WLAN(Wireless Local Area Network). The antenna for WLAN should show the characteristic of omni-directional radiation pattern. First, to obtain the omni-directional radiation pattern the proposed dual-band antenna has an orthogonal inverted triangular type element at the center and locates four resonating elements symmetrically around it. Also, for the purpose of easy manufacturing and miniaturization of the antenna, we changed the central element which had the orthogonal inverted triangular type structure into the plate type. Measured $S_{11}$ for the proposed dual-band plate type antenna showed characteristic which was less then -12.8 dB for WLAN frequency bands. Measured results for the maximum gain showed 3.17 dBi at 2.44 GHz, 5.38 dBi at 5.77 GHz with omni-directional radiation pattern. The implemented antennas showed applicable performances for the access point of WLAN.

• The KIPS Transactions:PartD
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• v.11D no.1
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• pp.173-182
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• 2004

The research to estimate development effort of software has been progress. But, it is not easy gain that testing data for estimating of development effort. Also, if we get the testing data, it is important that analysis testing data. In this paper, we study the data analysis of software development effort using the 789 software development projects which developed in the 1990's. Software development scale and software development team site are various. Using the characteristic of factor, we have to study characteristic of data and we estimate the development effort step by step. First, we prove the difference of development effort with the 789 project data according to development type, development environment, the development language etc. Also, we execute the crosstabs analysis that team site and function point.

• Korean Institute of Interior Design Journal
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• v.22 no.2
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• pp.186-193
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• 2013

In the commercial space, the modern consumers want to consume not only product but also culture. Thus, the modern commercial space tries to induce the customer's concern and purchase to the differentiated design. The introduction of this 'the natural element' delivers the pleasure and stability to the consumer buying process and availability is enlarged. Therefore, the purpose of study is gain that expression and characteristic method of the natural element in the commercial space. The detailed study method are as follows. First, the study looks into the natural element expression tendency in the modern space. Second, the expression type of the natural element was classified as 'Reappearance', 'Transformation', and 'Fuse' based on the preceding research. And according to the content of the expression type, subdivided method of 'Inclusion' and 'Replication' of 'Reappearance' and method of 'Imitation' and 'Association' of 'Transformation' and method of 'Juxtaposition' and 'Combine' of 'Fuse'. Third, the result of analyze the characteristic of expression of the natural element of the besides the commercial space case 20 place is as follows. First, 'Inclusion' of 'Reappearance' introduced the external scenery or planned garden as the inside through the opening. 'Replication' is used for decorative purposes or functional purposes as the natural element. 'Imitation' of 'Transformation' imitated the form, pattern, and color of the natural element and was mainly expressed in the wall and objet. The method of 'Association' expressed the concept of the natural element for the whole of the space and a portion of the wall and objet repetitively. As for 'Juxtaposition', mixture of 'Reappearance' had a good visual effect, because it can be obtained the external-internal nature. As for 'Combine', mixture of 'Replication' and 'Imitation' was the most common method. Thus, the study results are expected to be utilized as base date in designing the commercial with development of the natural element application method.

• Cartoon and Animation Studies
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• s.10
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• pp.33-53
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• 2006

On this treatise , we analyze the characteristic of a cartoon secured it's position as new popular media of popular culture in Korean modern society. And the purpose of this study is clarifying the social meaning of cartoon for formulating historical position of Korean cartoon. For a cartoon expand the sphere of research as a study, and secure the position as a unique popular culture genre in Korean society , we need to consider and ensure historical position which Korean cartoon had from the quickening period of it. As a visual culture, a cartoon realized stately the purpose of communication media at that society which had high illiteracy rate. In this upheaval at Korean society , the appearance of modern cartoon had became very important measure of propaganda and education for enlightened intellectuals who had enlightened the people and endeavored to regain sovereignty. Conversely, it also had became a measure of pro-Japanese. Also, it was important measure of securing a reader to a publishing company managed a media for commercial gain. Therefore, on this thesis, we judged that the quickening period of Korean cartoon is from the early 1900's (an occupation period of Japan) till 1945 (the day of liberation), and found the characteristic of Korean cartoon on basis of this period.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.10
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• pp.889-895
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• 2002

Wafer level packaging is gain mote momentum as a low cost, high performance solution for RF-MEMS devices. In this work, the flip-chip method was used for the wafer level packaging of RF-MEMS devices on the quartz substrate with low losses. For analyzing the EM (electromagnetic) characteristic of proposed packaging structure, we got the 3D structure simulation using FEM (finite element method). The electric field distribution of CPW and hole feed-through at 3 GHz were concentrated on the hole and the CPW. The reflection loss of the package was totally below 23 dB and the insertion loss that presents the signal transmission characteristic is above 0.06 dB. The 4-inch Pyrex glass was used as a package substrate and it was punched with air-blast with 250${\mu}{\textrm}{m}$ diameter holes. We made the vortical feed-throughs to reduce the electric path length and parasitic parameters. The vias were filled with plating gold. The package substrate was bonded with the silicon substrate with the B-stage epoxy. The loss of the overall package structure was tested with a network analyzer and was within 0.05 dB. This structure can be used for wafer level packaging of not only the RF-MEMS devices but also the MEMS devices.

• The Journal of the Korea Contents Association
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• v.11 no.2
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• pp.229-237
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• 2011

All over the world, the interest in technology and industrial value has been increasing rapidly due to the continuing commercial successes of three dimensional films. However, after the commercial success of , without exception, lots of three dimensional films had been produced thoughtlessly. Hereby, these films incurred a censure owing to bad degree of completion related to insufficient storytelling and directing. For three dimensional films, characteristic of producing should be considered perfectly in the planning stage unlike previous films. This study concentrates upon proper directing for three dimensional films, and analyzes the method of it, roughly divided into three parts ; the lapse of time, directing the screen which can highlight space sense, and the point of sight. Henceforth, The demand of three dimensional contents will increase all around the world, at such time, we also should take note of the change, and then produce excellent contents which can lead to have a chance to gain the supper hand in the market of three dimensional contents.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.849-852
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• 2007

In this paper, the high gain and the broadband microstrip patch antenna, which is applicable to 5 GHz band wireless LAN, is designed in order to integrate IEEE 802.11a's detailed standards($a:5.15{\sim}5.25$, $b:5.25{\sim}5.35$, $c:5.725{\sim}5.875$ [GHz]). Designed patch antenna has settled resonance frequency by insert substance(polyurethane: ${\varepsilon}_r=6.5$) between the separated parasitic patch and radiation patch for the purpose of miniaturize. And the form (${\varepsilon}_r=1.03$) were to fix the separated radiation patch and ground plans by air. Designed frequency bandwidth(VSWR 2:1) of the antenna showed broadband characteristic of $4.9[GHz]{\sim}6.1[GHz]$ to about 1.2[GHz]. Also the E-plan and H-plan profit 12[dBi] above, the 3[dB] beamwidth showed the characteristic over the E-plan $30^{\circ}$ and H-plan $60^{\circ}$ to be improved.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.2
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• pp.125-130
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• 2011

In this paper, SIW-based $2{\times}4$ uniform array antenna with a sequentially fed 8-way power divider with an equal division characteristic is proposed for an application of X-band satellite communication. In particular, sequential feeding structures with a progressive phase difference of 90 degrees between the nearest elements have been suggested to protect the cancellation of electric fields due to the array alignments and to enhance the purity of RHCP(Right-Handed Circular Polarization). The obtained results according to the return loss bandwidth, RHCP antenna gain, axial ratio bandwidth are 760 MHz ranging from 7.90 to 8.66 GHz under the criterion of less than -10 dB, 14.3 dBic at 8.3 GHz, and 600 MHz from 8.15 to 8.75 GHz, respectively. In addition, it is observed that the equal-division characteristic of SIW-based 8-way power divider is approximately -9.2 dB in all ports.