• Journal of information and communication convergence engineering
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• 제7권2호
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• pp.235-240
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• 2009

This paper combines various detection techniques and analyzes their performances in detecting the transmission information of the D-STTD scheme that uses, in parallel, the STTD scheme known as the Alamouti code. The D-STTD scheme adopts one of the STTD schemes for transmission to acquire diverse effects and uses another form of STTD for multiplexing effects. Due to the multiplexing effect that transmits different data, it is difficult to apply D-STTD to the conventional STTD combining technique. This paper combines the D-STTD system with linear algorithm, SIC algorithm and OSIC algorithm known as multiplexing detection scheme based on MMSE scheme. And we propose the detection scheme of the D-STTD using MAP algorithm and analyze the performance of each system. The simulation results showed that the detector using iterative algorithm has better performance than Linear MMSE Detector. Especially, we can show that the detector using MAP algorithm outperforms conventional detector.

• Journal of Magnetics
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• 제20권3호
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• pp.302-307
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• 2015

The purpose of the study was to identify how isotope and magnetic resonance imaging (MRI) contrast media impact on noise to computed tomography (CT) examination. For the study, divide the phantoms to two groups: 1) saline, saline + different kinds of contrast agent without $^{99m}Tc$ administration; 2) $^{99m}Tc$ administration: saline, saline + different kinds of contrast agent with $^{99m}Tc$ administration. CT contrast agent was used for Iopamidol$^{(R)}$ and Dotarem. And MRI contrast agent was used for Primovist$^{(R)}$ and Gadovist$^{(R)}$. To obtain an image, we used CT scanner. With an obtained image, we set the $1cm^2$ region of interest in the middle of bottle to measure the noise and CT number. As a result, there was no difference in CT number before and after inserting $^{99m}Tc$ into all contrast media including Normal Saline. However, when it comes to Noise, there was a difference before and after inserting $^{99m}Tc$ into every contrast media except MRI contrast media such as Primovist$^{(R)}$ and Gadovist$^{(R)}$.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1999년도 KOBA 방송기술 워크샵 KOBA Broadcasting Technology Workshop
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• pp.213.1-218
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• 1999

A virtual studio is a new video production environment using interactive computer graphics and imaging media technology. The traditional chroma-keying with two-dimensional background is replaced by an advanced keying method with a dynamic computer-generated, three-dimensional background. We have developed a virtual studio system that is practical to use in the real production environment. It has not only essential features that are common among various commercial virtual studio systems, but also unique feature that help the producer to construct virtual studio sets and scenarios efficiently such as span graph, robust backup controller, and 3 dimensional character generator supporting all languages. Our virtual studio system was used in live broadcasting and proved that the system was practical enough. In this paper, we will introduce the structure and the major features of our system, called VdreamSet, and application examples to broadcasting.

• Journal of Public Diplomacy
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• 제1권1호
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• pp.57-79
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• 2021

Drawing on the theories of mediated public diplomacy, intermedia agenda-building, and homophily, this study aims to compare the effectiveness of the public diplomacy efforts made by the Saudi and Qatari governments during the Gulf diplomatic crisis. The study examines the respective international agenda-building influence of the state-sponsored media from the two competing Gulf states on the regional and international media's coverage of the crisis. Results show that, compared to Saudisponsored Al Arabiya, Qatari-sponsored Al Jazeera was more effective in shaping the agendas of the regional and international media. Whereas Al Arabiya has a weak first-level agenda-building influence and a moderate-to-strong influence at the second and the third levels, Al Jazeera demonstrates a strong agenda-building influence on the foreign media outlets at all of the three levels. We also analyze the impact of political proximity and the language of the media content (English or Arabic) on the agenda-building relationships. Still, the results suggest that, compared to Al Arabiya, Al Jazeera was more successful in shaping the agendas of the regional and international news media-no matter where they are based in the allied or the opposing countries. Also, we observe a higher level of consistency between Arabic- and English-language content in Al Jazeera.

• 한국멀티미디어학회논문지
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• 제24권11호
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• pp.1526-1537
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• 2021

Due to the difference between the underwater communication environment and the terrestrial communication environment, the radio communication mainly used on the ground cannot be used in underwater. For this reason, in the underwater communication environment, various communication media such as acoustic waves, infrared rays, light and so on has been studied, but there exist several difficulties in operating them individually due to their physical limitations. The concept for overcoming these difficulties is the very underwater multi-media communication, a method to select a communication medium best suitable for the current underwater environment among underwater communication multimedia whenever there occurs underwater communication failure. In this paper, we present an underwater multi-media communication network based on star topology and a fragmentation and reassembly technique to solve the problems caused by the different MTU (Maximum Transmission Unit) sizes among different underwater communication media. We also present the estimations and analysis on processing times in each of fragmentation and reassembly and the total data amount for transmitting fragments in our proposed underwater multi-media communication network.

• ETRI Journal
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• 제38권4호
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• pp.665-674
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• 2016

We designed and fabricated a semiconductor optical amplifier-integrated dual-mode laser (SOA-DML) as a compact and widely tunable continuous-wave terahertz (CW THz) beat source, and a pin-photodiode (pin-PD) integrated with a log-periodic planar antenna as a CW THz emitter. The SOA-DML chip consists of two distributed feedback lasers, a phase section for a tunable beat source, an amplifier, and a tapered spot-size converter for high output power and fiber-coupling efficiency. The SOA-DML module exhibits an output power of more than 15 dBm and clear four-wave mixing throughout the entire tuning range. Using integrated micro-heaters, we were able to tune the optical beat frequency from 380 GHz to 1,120 GHz. In addition, the effect of benzocyclobutene polymer in the antenna design of a pin-PD was considered. Furthermore, a dual active photodiode (PD) for high output power was designed, resulting in a 1.7-fold increase in efficiency compared with a single active PD at 220 GHz. Finally, herein we successfully show the feasibility of the CW THz system by demonstrating THz frequency-domain spectroscopy of an ${\alpha}$-lactose pellet using the modularized SOA-DML and a PD emitter.

• 디지털콘텐츠학회 논문지
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• 제18권6호
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• pp.1017-1024
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• 2017

기술의 발달은 콘텐츠 미디어의 변화를 가져왔다. 구술 시대의 음성, 소리 미디어에서 시작하여 텍스트, 페인팅을 거쳐, 사실성의 사진 미디어, 이미지에 사운드를 더한 영상 미디어의 발달로 이어져 왔다. 여기서 생각해보아야 할 것은 기술의 발달로 인한 미디어의 변화라는 일방적 영향만이 아니라, 어떤 세대가 어떤 미디어를 접하느냐에 따라 정보의 이해도 및 집중력, 몰입도 등이 달라진다는 것이다. 이에 디지털을 주미디어로 활용하고 있는 디지털 네이티브 세대에 주목하게 된다. 디지털 네이티브 세대의 특징으로는 시각정보를 빠르게 처리하며, 멀티태스킹이 가능하고, 분할주의 능력을 지니고 있는 세대로 연구된 바 있다. 이에 본 논문에서는 디지털 네이티브 세대를 위하여 움직이는 픽토그램을 제안, 픽토그램 중에서도 한계성을 보이고 있는 비상구 픽토그램을 움직이는 픽토그램으로 제안하였으며, 설문지를 통하여 근거를 마련하였다. 디지털 네이티브 세대 특성에 맞춘 새로운 동적 픽토그램, 더 나아가 인터랙티브 동적 픽토그램은 생각하고 연구되어야 하는 분야로 본 논문은 첫 발을 내딛는 연구라고 볼 수 있다.

• 디자인학연구
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• 제12권3호
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• pp.5-14
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• 1999

급속하고 광범위하게 변화하는 경쟁적 환경 속에 있는 우리는 교육의 역할이 더욱 중대함을 인식하고 있다. 우리 사회가 처한 도전은 어떻게 정보를 다루고 그것을 어떻게 지식으로 전환하느냐이다. 이미 많은 학교에서 컴퓨터를 사용하여 학습효과를 향상하려고 노력하고 있다. 인터그레이티드 미디어(Integrated Media)의 교육활용은 학습내용을 새롭고 흥미롭게 제시하는 것 이외에도 종전의 미디어 시스템들이 가지지 못했던 학생이 직접 참여하는 방법으로 배우는 과정에 있어 시각, 청각, 그리고 시뮬레이션의 경험을 사용한 대화형 교육의 높은 유용성 즉, 상호작용적 특성을 가질 뿐만 아니라 대량의 정보를 저장, 통신, 관리, 처리하는 능력이 탁월하다는 효율성과 효과성을 든다. 본 연구는 인터그레이티드 미디어(Integrated Media)의 본질을 파악하고 아동들의 심리 및 인지능력을 검토하여 아동을 위한 교육결과물을 제작하는 데 있어 실질적인 문제제기를 하였으며, 그 해결방안으로써 부분적이기는 하나 그것의 교육효과와 효율성을 높이기 위한 디자인적인 관점과 내용면의 해결책을 제시하였다.

• The Korean Journal of Pain
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• 제7권2호
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• pp.211-216
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• 1994

Celiac plexus block is performed to relieve intractable upper abdominal cancer pain. Generally, celiac plexus blocks have been performed under control of X-ray fluoroscopy to determine the position of the needle tip and the spread of contrast media. During the period from March 1992 to February 1994, we have performed 21 cases of neurolytic celiac plexus block to alleviate pain of intra-abdominal malignancy. We retrospectively evaluated the location of the needle tip and the spread of contrast media. P-A views of simple abdomen demonstrated the locations of the needle tip: 66.7% of the left needle tips were in upper 3/1 of L1 (6 cases) and $T_{12}-L_1$ interspace (8 cases), 50% of the right needle tips were in upper 1/3 of $L_1$, (6 cases) and $T_{12}-L_1$ interspace (4 cases). Contrast media from the right needle spread upward to middle 1/3 of $T_{10}$ (5 cases) and middle 1/3 of $T_{11}$ (5 cases), downward to middle 1/3 of $L_1$ (6 cases) and lower 1/3 of $L_1$ (3 cases). Contrast media from the left needle were spread upward to middle 1/3 of $T_{10}$ (5 cases) and evenly to other spaces, downward to middle 1/3 of $L_1$, (4 cases) and $L_1-L_2$ interspace (6 cases). We analyze the spread of contrast media according to distance from needle tip by authors score system. Contrast media of right needle spread upward 6.1 and downward 3.4, that of left needle spread upward 6.5 and downward 3.7.

• 한국환경복원기술학회지
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• 제20권5호
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• pp.59-66
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• 2017

Preeminent water treatment plans are essential to preserve the water quality of aquatic biotopes. Previous studies have not been sufficient to provide cost-effective maintenance method since they focused only on the purification of deteriorated water that requires a continuous supply of clean water. This study proposes an economical method of water quality maintenance using water treatment media block constructed vertically using porous ceramics, zeolite, and river pebble. The water treatment media block does not require a separate purification area because it functions as a purifier within the ecological pond which can maximize the biotope area. To evaluate the performance of the water treatment media block, we longitudinally tracked the change of water quality indicators (pH, TDS, COND, DO, T-P, T-N, COD) suggested by Water Environment Standards, Ministry of Environment, Republic of Korea. We compared the water quality of one control (A: general ecological pond composition method of the laminated structure) and two experimental groups (B: a combination of aquatic plants and a water treatment media block, C: a water treatment media block only). As a result, we confirmed that the water treatment media block is an efficient and economical method to maintaining the water quality of the ecological pond for a long time. The water treatment media block will be a great help in providing a better aquatic biotope space for aquatic insects and fishes living in clear water.