• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.1
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• pp.42-48
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• 2006

In this paper a joint detection method for other cell interference cancellation is proposed in the next generation hybrid TD-CDMA mobile communication systems. A joint detection technique, a most characteristic feature of hybrid TD-CDMA mobile communication systems. retrieves users' data in the same time slot simultaneously with the elimination of multiple user interference. Previously a two stage joint detection method was proposed to cancel other cell interference as well as multiple user interference in the target cell. However the previous scheme does not have concrete ways to recognize other cell users who give major interference to the target cell. Thus all users in neighbor other cells has to be jointly detected and it causes huge complexity of the two stage joint detection. In this paper a method is proposed to perform two stage joint detection according to users' interference with the target cell. Performances of the proposed scheme are investigated through simulations and compared to the previous method the proposed method has no performance degradation and also lower the complexity of two stage joint detection significantly.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.3
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• pp.306-313
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• 2012

In order to enhance the isolation level between two dual-band E-slot microstrip patch antennas, EBG structure which operates in UMTS Tx(1.92~1.98 GHz) and Rx(2.11~2.17 GHz) band is proposed. The proposed EBG structure made with a periodic array of two different size EBG unit cells which has a modified mushroom-type for isolation improvement between two antennas. They do not share a common ground plane of the microstrip patch antenna. Overall size of the fabricated antenna is $210.5mm{\times}117mm$. The two different EBG unit cell sizes are $15.6mm{\times}4mm$ and $17.4mm{\times}4mm$, respectively. It was etched on the FR-4 substrate(thickness=3.93 mm, ${\varepsilon}_r$=4.6). The experiment results show that the isolation level between antennas in Tx/Rx band were improved by about 9 dB and 12 dB, respectively, through the use of the proposed EBG structure.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.865-870
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• 2003

A motion controller has been used variously in industry such as semiconductor manufacture equipment, industrial robot, assembly/conveyor line applications and CNC equipment. There are several types of controller in motion control. One of these is a PC-based motion controller such as PCI or ISA, and another is stand-alone motion controller. The PC bus-based motion controller is popular because of improving bus architectures and GUI (Graphic User Interface) that offer convenience of use to user. There are some problems in this. The PC bus-based solution allows for only one of the form factors, so it has a poor flexibility. The overall system package size is bigger than other motion control system. And also, additional axes of control require additional slot, however the number of slots is limited. Furthermore, unwieldy and many wirings come to connect plants or I/O. The stand-alone motion controller has also this limit of axes of control and wiring problems. To resolve these problems, controller must have capability of operating as stand-alone devices that resides outside the computer and it needs network capability to communicate to each motion device. In this paper, a network-based stand-alone motion system is proposed. This system integrates PC and motion controller into one stand-alone motion system, and uses CAN (Controller Area Network) as network protocol. Single board computer that is type of 3.5" FDD form factor is used to reduce the system size and cost. It works with Windows XP Embedded as operating system. This motion system operates by itself or serves as master motion controller that communicates to slave motion controller. The Slave motion controllers can easily connect to master motion system through CAN-network.

• Korean Journal of Computational Design and Engineering
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• v.10 no.4
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• pp.244-253
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• 2005

In the initial ship design stage of shipyards, the hull form design, the basic design (compartment modeling and ship calculation), and the hull structural design are being performed by different systems. Thus, the problem on interfaces between these systems occurs. To solve this, we developed the hull form design system 'EzHULL' and the compartment modeling and ship calculation system 'EzCOM-PART' for developing finally an integrated ship design system. And, in this study, we present an object-oriented hull structural design .system 'EzSTRUCT', which is developed recently. A structural design in an initial design stage can be frequently changed, because the design is not firmly determined yet. Therefore, designers perform the simplified structural modeling with bigger structural parts (or objects) such as deck, longitudinal bulkhead, etc. in the initial design stage, and the detailed structural modeling with smaller structural parts such as plate, seam, slot, etc. in the detailed design stage. However, the existing hull structural CAD system used in a shipyard is not efficient in generating a 3D CAD model in the initial design stage, because it has difficulty in handling frequent changes in design. Therefore, designers initially draw 2D drawings in the initial design stage, and generate the 3D CAD model from these 2D drawings in the detailed design and production design stages. In this study, the hull structural design system, which can efficiently generate a 3D CAD model through rapid modeling at an initial design stage, was developed in this study To evaluate the applicability of the developed system, we applied it to hull structural modeling of various ships such as a VLCC, a bulk carrier, etc. As a result, it could efficiently generate a 3D CAD model of a hull structure.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.64-73
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• 2020

The importance of international co-production that enables content production, diversification of overseas markets, and diversification has been highlighted as demand for content has soared due to intensifying competition between media outlets, while contents provision has become easier due to changes in media environment such as convergence of broadcasting and communication and the spread of mobile Internet. In particular, the boom in Korean dramas, called the Korean Wave in China, opened up a new market after "My Love from the Star" in 2014, and in 2016, Netflix's entry into Korea served as an opportunity for local broadcasters and producers to seek international co-production. In addition, "Good Doctor" which was aired on American Broadcasting Co. (ABC) in 2017, has topped the same time slot for the first time in 29 years, and is set to air season 4 this fall. Accordingly, overseas broadcasters and production companies wanted to collaborate with domestic broadcasters and producers, and since 2011, they have conducted a total of 12 co-produced dramas until 2019. Unfortunately, however, there are few studies related to international co-production dramas in the domestic industry and academia. In this paper, we present to help Korea, which used to be a powerhouse in complete export-type content, move toward becoming a powerhouse in international co-produced dramas. In addition, it is meaningful that the research focused on the current status and achievements of international co-production dramas, which have not been studied much, and the diversity of international co-production dramas in the future through the analysis of the form and structure of international co-production.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.7
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• pp.1128-1138
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• 2000

This paper presents two different approaches for channel estimation of IMT-2000 pilot symbol-assisted W-CDMA reverse link over Rayleigh fading channels of one and two paths. By obtaining BER performance through computer simulations, the proposed algorithms of 2-point second-order interpolation and IDD BWMA are compared with the performance of existing interpolation and adaptive algorithms. The BER performance of the proposed algorithms is superior to WMSA, linear and second-order Gaussian interpolation, LMS, and RLS algorithm in fast fading channels. In particular, the BER performance of the IDD BWMA algorithm is nearly insensitive for Doppler frequency within simulation range $E_b/N_0$ = 28 dB. The two proposed algorithms also have relatively simple structure and similar processing delay in comparison to the existing algorithms. Therefore, these algorithms are more suitable for high-speed mobile communication environments.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.8
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• pp.746-752
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• 2009

In this paper, we deal with the development of an optimal design program for a triple-band PTFA(Planar Inverted-F Antenna) of 433 MHz, 912 MHz and 2.45 GHz by using evolution strategy. Generally, the resonance frequency of the PIFA is determined by the width and length of a U-type slot used. However the resonance frequencies of the multiple U slots are varied by the mutual effect of the slots. Thus the optimal width and length of U-type slots are determined by using an optimal design program based on the evolution strategy. To achieve this, an interface program between a commercial EM analysis tool and the optimal design program is constructed for implementing the evolution strategy technique that seeks a global optimum of the objective function through the iterative design process consisting of variation and reproduction. The resonance frequencies of the triple-band PIFA yielded by the optimal design program are 430 MHz, 910.5 MHz and 2.458 GHz that show a good agreement to the design target values.

• The Journal of the Korea Contents Association
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• v.8 no.7
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• pp.58-65
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• 2008

The overlay multicast that has been recently presented as an alternative for the IP multicast has been getting much attention by the advancement of network techniques to enforce routing in application-levels. In this paper, we verified the efficiency of Internet broadcasting through comparing latency time of TBCP with mOBCP that have distributed Tree-first based spanning-tree structures in overlay multicast techniques. We also propose effective tree structures that minimize latency time and provide competent service by choosing optimum parent nodes early in the base of these two methods over the same time slot in multi-user connection. The results of our comparison showed that average latency time in mOBCP techniques declined by 36% from those of TBCP technique.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1511_1512
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• 2009

This paper presents a polarization switching antenna integrated with silicon RF MEMS SPDT switches in the form of a package. A low-loss quartz substrate made of SoQ (silicon-on-quartz) bonding is used as a dielectric material of the patch antenna, as well as a packaging lid substrate of RF MEMS switches. The packaging/antenna substrate is bonded with the bottom substrate including feeding lines and RF MEMS switches by BCB adhesive bonding, and RF energy is transmitted from signal lines to antenna by slot coupling. Through this approach, fabrication complexity and degradation of RF performances of the antenna due to the parasitic effects, which are all caused from the packaging methods, can be reduced. This structure is expected to be used as a platform for reconfigurable antennas with RF MEMS tunable components. A linear polarization switching antenna operating at 19 GHz is manufactured based on the proposed method, and the fabrication process is carefully described. The s-parameters of the fabricated antenna at each state are measured to evaluate the antenna performance.

• Journal of Korean Physical Therapy Science
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• v.8 no.2
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• pp.989-995
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• 2001

The purpose of this paper was to enable patients, who suffer from muscle damage. to return to their normal activities as soon as possible. With this in mind. this experiment was carried out to make an analysis of a variety of ingredients subjected to changes when muscle damage or muscle soreness was treated with aceclofenac, NSAID, and to find out what effect the anti-inflammation produced in relation to such symptoms. It made use of male rats (Sprague-Dawely) as subjects. It carried out two kinds of experiments: one was a preliminary experiment from March 15, 2001 to March 20, 2001 and the other was a main experiment from March 30, 2001 to April 15, 2001. Each group was composed of five rats. In case of DOMS. it worked with eight male adults from April 20. 2001 to April 30, 2001. It have come up with the following conclusions: 1. The leucocytes and erythrocytes of the experiment group were decreasing with the lapse of time in comparison with those of the contrast group. And a decrease in the number of hemoglobin had remarkably statistic significance (P<0.05). 2. Neutrophil, Lymphocyte and Monocyte decreased in 36, 24, 12 and 24 hours, respectively, which means that they had a significant difference(P<0.05). 3. CPK and LDH were reduced remarkably through the whole time slot in comparison with the contrast group, and had statistic significance(P<0.05). The findings above show that anti-inflammations cure bruises or damage or myalgia in a shorter period of time than the normal recovery of other treatment.