• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.3A
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• pp.383-390
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• 2000

In this paper, an adaptive power control algorithm in the DS/CDMA system is proposed. The currently used transmitter/receiver based on IS-95 and the radio propagation channel under mobile communication environments are modeled. Theses are the key features for the simulation to analyse the performance of power control. the distribution of the received SIR(signal to interference ratio)and the bit error probability are the required parameters for the performance analysis. Furthermore the influence of the power control command error on the above parameters are analyzed. By using the performance analysis of IS-95 and the occurrence of burst errors that is characteristic for wireless channels. the new power control algorithm is proposed. The proposed power control algorithm increases the SIR which results in a better service quality and an enhancement in the system capacity.

• International Journal of Automotive Technology
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• v.7 no.4
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• pp.501-508
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• 2006

The effect of chemical additives, such as dimethyl ether(DME), ethanol, carbon disulfide on the soot formation were examined numerically. ill this study, the Frenklach soot mechanism was used as a base mechanism to predict the soot formation in the ethane flame. The combination of Westbrook's DME mechanism, Marinov's ethanol mechanism, and chemical kinetic mechanism for hydrogen sulfide and carbon disulfide flames was made with the base mechanism because the DME, ethanol, $CS_2$ additives are added into the ethane fuel. CHEMKIN code was used as a numerical analysis software to simulate the effect of chemical additives on reduction of the polycyclic aromatic hydrocarbons(PAH's) which are soot precursors. From the numerical results it is observed that addition of DME, ethanol and $CS_2$ into ethane fuel can reduce PAH species significantly. That means theses additives can reduce soot formation significantly. Results also strongly suggest suppression of soot formation by these additives to be mainly a chemical effect. Hand OH radicals may be the key species to the reduction of PAH species for additives.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.66-72
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• 2000

We have scanned the several seismic traces of earthquakes and blasts observed from the digital new type seismograph instruments of KMA from Jan. 2000 to Aug. 2000. From these data, good quality data which have high signal/noise ratio were selected and they were transformed into ascii data from binary data(mini-seed format). The hypo71 program and P-S was applied in order to determine the location of epicenter, origin time and the magnitude. From these data, the 18 earthquakes and 3 blasts, 207 seismic records consist of 359 directional components were calculated. Using theses ground acceleration data, acceleration, velocity, and displacement response spectrums of the structures were calculated and they could be represented in a picture by the form of tripartite response spectrum. In the result, response spectrums of the 359 directional components of the above seismic data records were obtained respectively.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.2043-2045
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• 2004

This thesis complemented the weak points that the existing theses did not represented a phase characteristic as the equivalent circuit by applying 4-port simulation to DGS (Defected Ground Structure) characteristic and an equivalent circuit, which are the transmission line structure that has the defect made in the ground surface. We used a distribute device and a lumped device, obtained the equivalent circuit by applying the structure of balun to a discontinuous part. An indicated DGS (Defected Ground structure) is a dumbbells-shaped single defect, we indicated satisfying a magnitude and phase characteristics by applying this equivalent circuit.

• Korean Journal of Bronchoesophagology
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• v.13 no.2
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• pp.57-60
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• 2007

The management of penetrating zone II neck injuries without hard signs of vascular injury has been controversial. The controversy lies between mandatory exploration and a selective approach to the management of theses injuries. Authors that advocate mandatory exploration state its low complication rate and high sensitivity in support of this approach. Surgeons in support of selective management argue selective management has comparable efficacy with lower morbidity in comparison with mandatory exploration. Recently we experienced a case of stab wound near vertebral artery and operatively explored, therefore we report a case along with review of literature.

• ETRI Journal
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• v.27 no.1
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• pp.13-21
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• 2005

Many multicast applications, such as video-on-demand and video conferencing, desire quality of service (QoS) support from an underlying network. The differentiated services (DiffServ) approach will bring benefits for theses applications. However, difficulties arise while integrating native IP multicasting with DiffServ, such as multicast group states in the core routers and a heterogeneous QoS requirement within the same multicast group. In addition, a missing per-flow reservation in DiffServ and a dynamic join/leave in the group introduce heavier and uncontrollable traffic in a network. In this paper, we propose a distributed and stateless admission control in the edge routers. We also use a mobile agents-based approach for dynamic resource availability checking. In this approach, mobile agents act in a parallel and distributed fashion and cooperate with each other in order to construct the multicast tree satisfying the QoS requirements.

• The Journal of Sustainable Design and Educational Environment Research
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• v.5 no.1
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• pp.1-10
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• 2006

The purpose of this study is to clarify the actual conditions of the use and the plan of lifelong education facilities in national university of industry. This article discuses about the basic characteristics of the plan composition and the education programs of 8 lifelong education facilities in national university of industry. The results of this study are summarized as follows; 1) Needed spaces should functionally designed considering that basic and culture lecture, occupation skill and expert education, hobby/amusement/leisure, health/sanitation/sports, tradition culture understanding education among education programs of lifelong education facilities in universities are mainly constituted and occupation skill and expert education among theses are occupied with the most ratio. 2) Expansion of facilities is agent considering the number of students and lectures to be 3.0% from 1.7% of average ratio of continuous dimensions lifelong education facilities of each universities and composition following scale of the lecture room is set by organizing the number of students per lecture to small groups.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1897-1900
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• 2004

In recent years, a lot of industrial equipments have serial communication channel such as FieldBus (CAN, Profibus, etc.) or Ethernet that provides real time communication between industrial equipments. Theses applications include gantry crane, robot, chip mounter, etc.. In this paper, we discuss the synchronization technique for networked multi-motor systems where controllers (commercial servo amps) are distributed and interconnected by CAN (Controller Area Networks). We first describe the equivalent model for the individual servo-amp and motor using the frequency response. We design the $H{\infty}$ controller for motion synchronization. Finally, the synchronization technique using the equivalent model and the $H{\infty}$ controller is verified by the simulation and the experiment.

• The Research Journal of the Costume Culture
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• v.19 no.2
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• pp.402-415
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• 2011

The purpose of this study is to research the ideologies of African-American hair-styles according to cultural phenomena. This is a qualitative research using the books and theses about society, culture, hair and beauty, and materials of internet. The results are; Firstly, African-Americans are citizens or residents of the United States who have origins in any of the black populations of Africa. About 75 percent of the dark-skinned people on this continent have hair labeled "kinky". Secondly, African hair-styles expressed Supernaturalism and Traditionalism in the formative period of African culture. African-American hair-styles reflected Colonialism in the period of slaves. African-American citizen's hair-styles showed Nationalism after 1960s' Black Pride Movement in the period of settlement in America, and expressed De-territorialism since the boom of 1970s' Reggae. Today, the wearing of dreadlocks, cornrows, and afros has transcended racial and religious barriers. No longer necessarily reflections of ancient traditions and cultural identification, they are just as often fashion items.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.313-313
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• 2016

Transparent conductive oxide (TCO) films have many disadvantages, such as rarity, possible exhaustion, process temperature limitations, and brittleness on a flexible substrate. In particular, as display technology moves toward flexible displays, TCO will become completely unsuitable due to its brittleness. To address theses issue, many researchers have been studying TCO substitutes. In recent efforts, metal nanowires, conducting polymers, carbon nanotube networks, graphene films, hybrid thin films, and metal meshes/grids have been evaluated as candidates to replace TCO electrodes. In this study, we fabricated the TCO film with Ag meshes shape using polystyrene (PS) beads monolayer on the substrate. The PS beads were used as a template to create the mesh pattern. We fabricated the monolayer on the flexible substrate (PES) with the well-aligned PS beads. Electrodes with Ag mesh shape were formed using this patterned monolayer. We could fabricated the Ag mesh electrode with the sheet resistance with $8ohm{\Omega}/{\Box}$.