• Journal of Sensor Science and Technology
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• 제12권4호
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• pp.149-155
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• 2003

A PMOSFET photodetector for highly-sensitive active pixel sensor(APS) is presented. This sensor uses 5V power supply and has been designed and fabricated using I-poly and 2-metal $1.5{\mu}m$ CMOS technology. The feature of a PMOSFET photodetector is that the polysilicon gate of the PMOSFET was connected to n-well, in order to increase the photo sensitivity. The designed MOS photodetector has similar $I_{DS}-V_{DS}$ characteristics with a standard MOSFET. One dimensional image sensor with 16 pixels based on the PMOSFET photodetector has also been designed and fabricated. Unit pixel of the designed sensor consists of a PMOSFET photodetector and 4 NMOSFETs. Unit pixel area is $86{\mu}m{\times}90.5{\mu}m$ and its fill factor is about 12%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권9호
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• pp.3159-3176
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• 2014

This work presents an analysis of the buffer features of an access router, especially the size, the impact on delay and the packet loss rate. In particular, we study how these features can affect the Quality of Service (QoS) of multimedia applications when generating traffic bursts in local networks. First, we show how in a typical SME (Small and Medium Enterprise) network in which several multimedia flows (VoIP, videoconferencing and video surveillance) share access, the upgrade of the bandwidth of the internal network may cause the appearance of a significant amount of packet loss caused by buffer overflow. Secondly, the study shows that the bursty nature of the traffic in some applications traffic (video surveillance) may impair their QoS and that of other services (VoIP and videoconferencing), especially when a certain number of bursts overlap. Various tests have been developed with the aim of characterizing the problems that may appear when network capacity is increased in these scenarios. In some cases, especially when applications generating bursty traffic are present, increasing the network speed may lead to a deterioration in the quality. It has been found that the cause of this quality degradation is buffer overflow, which depends on the bandwidth relationship between the access and the internal networks. Besides, it has been necessary to describe the packet loss distribution by means of a histogram since, although most of the communications present good QoS results, a few of them have worse outcomes. Finally, in order to complete the study we present the MOS results for VoIP calculated from the delay and packet loss rate.

• Proceedings of the Acoustical Society of Korea Conference
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.977-983
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• 1994

In this paper we have evaluated the synthetic speech quality by the proposed TD-PCULI speech synthesis method. For the synthesis we have extracted parameters from the Korean monosyllables through the analysis of speech waveforms in the time domain. We have constructed the Korean data format dictionary for the synthesis-by-rule depending upon the frequencies of the Korean pronunciation large vocabulary dictionary, in which V type syllables are 19, CV type's are 80, VC type's are 30 and CVC type's are 100. And using them we have synthesized various Korean monosyllables, words and sentences. We have tested each 10 syllables selected according to the 4 Korean syllable types with the objective MOS(Mean Opinion Score) evluation method about the 4 items i.e., intelligibility, clearness, loudness, and naturality after selecting random group without the knowledge of them. And also we have tested the possibility to modify a duration and F0 into another forms with changing a duration (i.e., 150msec, 300msec, 500msec, 700msec and 1sec) and a central fundamental frequency(i.e., 80Hz, 118Hz, 140Hz, 170Hz, and 200Hz). As the results of experiments the noises occurred in the course of synthesizing the speech by the rules are removed to be a very clear level and we can find that the prosodic elements can be controled as a good condition.

• Journal of Chest Surgery
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• 제43권5호
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• pp.475-481
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• 2010

Background: We evaluated mid-term results of mitral annuloplasty using a flexible band and a completely rigid ring for mitral valve repair in patients with degenerative mitral regurgitation (MR). Material and Method: From January 2004 to September 2008, 71 patients (M:F=36:35, $55{\pm}13$ years) underwent mitral valve repair with mitral annuloplasty for degenerative MR. Ring annuloplasty was done using a Cosgrove-Edwards flexible band (Group I, n=43) or a Carpentier-Edwards classic ring (Group II, n=28). There were no differences in preoperative characteristics of the participants. Average duration of follow-up was 36 months (range: 2~69 mos). Result: There was no in-hospital mortality. Postoperative morbidity, which included atrial fibrillation (n=7) and low cardiac output syndrome (n=5) in groups I and II were similar. There was one late death in group II. The proportion exhibiting freedom from recurrent mitral regurgitation ($\geq$moderate) at 4 years in Groups I and II were, respectively, 94.5 and 91.8%, (p=0.695). Left ventricular ejection fraction decreased in the early postoperative period ($7{\pm}2$ days) and recovered by last follow-up ($25{\pm}16$ mos; p=0.002). The pattern was similar in groups I and II (p=0.905). Re-operation was performed in 3 patients (1 in Group I and 2 in Group II, p=0.316). Four-year event-free survival (free of adverse valve-related events) was 95.2% for Group I and 92.6% for Group II; this difference was not significant, p=0.646). Conclusion: The type of technique used in mitral annuloplasty to repair the mitral valve repair after degenerative MR did not affect mid-term clinical and functional results.

• Development and Reproduction
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• 제10권3호
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• pp.159-168
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• 2006

Rodents and many other mammals have two chemosensory systems that mediate responses to pheromones, the main and accessory olfactory system, MOS and AOS, respectively. The chemosensory neurons associated with the MOS are located in the main olfactory epithelium, while those associated with the AOS are located in the vomeronasal organ(VNO). Pheromonal odorants access the lumen of the VNO via canals in the roof of the mouth, and are largely thought to be nonvolatile. The main pheromone receptor proteins consist of two superfamilies, V1Rs and V2Rs, that are structurally distinct and unrelated to the olfactory receptors expressed in the main olfactory epithelium. These two type of receptors are seven transmembrane domain G-protein coupled proteins(V1R with $G_{{\alpha}i2}$, V2R with $G_{0\;{\alpha}}$). V2Rs are co-expressed with nonclassical MHC Ib genes(M10 and other 8 M1 family proteins). Other important molecular component of VNO neuron is a TrpC2, a cation channel protein of transient receptor potential(TRP) family and thought to have a crucial role in signal transduction. There are four types of pheromones in mammalian chemical communication - primers, signalers, modulators and releasers. Responses to these chemosignals can vary substantially within and between individuals. This variability can stem from the modulating effects of steroid hormones and/or non-steroid factors such as neurotransmitters on olfactory processing. Such modulation frequently augments or facilitates the effects that prevailing social and environmental conditions have on the reproductive axis. The best example is the pregnancy block effect(Bruce effect), caused by testosterone-dependent major urinary proteins(MUPs) in male mouse urine. Intriguingly, mouse GnRH neurons receive pheromone signals from both odor and pheromone relays in the brain and may also receive common odor signals. Though it is quite controversial, recent studies reveal a complex interplay between reproduction and other functions in which GnRH neurons appear to integrate information from multiple sources and modulate a variety of brain functions.

• Journal of the Korean Society of Costume
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• 제55권7호
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• pp.51-61
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• 2005

The purpose of this study is to identify function of make-up as an Important variable in terms of its influence to psychology of performers and outcome of their performance. From June to November 2004 performers in 4 types of fields, i.e., opera, musical, drama and dancing being performed in Seoul and Cheongju were chosen as subjects and totally 450 questionnaires were prepared and distributed and among them 416 were used as data for final analysis. For data analysis frequency analysis, factor analysis, T-test, one-way ANOVA, path analysis, chi-square test were conducted by means of SPS 12.0 and MOS 4.0 statistical programs and as ex post facto checking Duncan's multiful range test was conducted. Make-up is an important element in acting and it has great influence on level of psychological satisfaction of an individual. It was disclosed that psychological factor of concentration and lethargy have direct bearing on acting performance. In order to maximize actor or actresses performance skill perfect make-up is essential and role of make-up specialist can become a critical factor for inducing success in performance. Role and duty of make-up artists in terms of scope of their responsibility should be extended so that they may give their full support to the performers to be most successful in their performance.

• International journal of advanced smart convergence
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• 제4권1호
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• pp.18-30
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• 2015

As the speed of networks that subscribers can use has greatly increased, demand for high-quality broadcast content, such as from Internet Protocol Television (IPTV) and Video on Demand (VoD), is likewise increasing. Therefore, while broadcasters are increasing content and channels, they are striving to improve consumer quality of experience (QoE) to differentiate themselves from competitors, including by producing higher physical-quality content. Recently, subjective measurement methods have been internationally standardized as the most reliable approach for measuring and evaluating IPTV QoE. However, a majority of these methods are performed in experimental environments and are based on the extremely brief viewing period of approximately ten seconds using original reference videos. It is actually difficult to apply standard evaluation methods based on a ten-second viewing interval to assess real broadcast watching of IPTV or other services that involve a longer time (i.e., more than thirty minutes). In this paper, we therefore propose a method that accommodates actual viewing environments. Using the mean opinion score, we experimentally analyze the effects of evaluation interval changes under actual conditions in which IPTV service is provided. In addition, we propose improvements by applying the results into actual live broadcast IPTV service and by analyzing consumer service QoE.

• Journal of the Korean Institute of Telematics and Electronics A
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• 제28A권12호
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• pp.59-64
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• 1991

Thin (25-103$\AA$) SiO$_2$ films are grown using the rapid thermal oxidation processing at temperatures of 105$0^{\circ}C$-115$0^{\circ}C$ for 5-30 sec, in order to investigate the characteristics of ultra thin oxide. For measuring the thickness of oxide TEM, ellipsometry, and C-V method which is taken in the condition of small surface band bending are used and compared. When neglecting the small deviation affected by both interface state and moisture charge effect, those three methods described above give similar results. In order to examine the effect of rapid thermal annealing, part of samples are annealed in N$_2$ ambient. MOS capacitors are fabricated and the characteristics of I-V and C-V are measured. Measurements show that the activation energy of initial thickness of oxide grown during the ramp-up time is of 1.125eV and the activation energy of the oxidation rate is of 0.98eV. As oxidation temperature is increased, dielectric breakdown field E$_{BD}$ is decreased due to the increase of fixed charge density N$_f$ However, E$_{BD}$ is shown to be decreased as increasing the thickness of oxide. The increase of N$_f$ in the early stage of thermal annealing results in the decrease of E$_{BD}$.

• Transactions on Electrical and Electronic Materials
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• 제9권4호
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• pp.169-172
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• 2008

We attempted to fabricate carbon nanotube field effect transistor (CNT-FET) using single walled carbon nanotube(SWNT) on the heavily doped Si substrate used as a bottom gate, source and drain electrode were fabricated bye-beam lithography on the 500 nm thick $SiO_2$ gate dielectric layer. We investigated electrical and physical properties of this CNT-FET using Scanning Probe Microscope(SPM) and conventional method based on tungsten probe tip technique. The gate length of CNT-FET was 600 nm and the diameter of identified SWNT was about 4 nm. We could observed gating effect and typical p-MOS property from the obtained $V_G-I_{DS}$ curve. The threshold voltage of CNT-FET is about -4.6V and transconductance is 47 nS. In the physical aspect, we could identified SWNT with phase mode of SPM which detecting phase shift by force gradient between cantilever tip and sample surface.

• Journal of Sensor Science and Technology
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• 제13권2호
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• pp.90-95
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• 2004

Protein and gene detection have been growing importance in medical diagnostics. Field effect transistor (FET) - type biosensors have many advantages such as miniaturization, standardization, and mass-production. In this work, we have fabricated metal-oxide-semiconductor (MOS) FET that operates as molecular recognitions based electronic sensor. Measurements were taken with the devices under phosphate buffered saline solution. The drain current ($I_{D}$) was decreased after forming self-assembled mono-layers (SAMs) used to capture the protein, which resulted from the negative charges of SAMs, and increased after forming protein by 11.5% at $V_{G}$ = 0 V due to the positive charges of protein.