• Journal of the Korean Chemical Society
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• v.44 no.5
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• pp.453-459
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• 2000

FED has deserved an intensive attentioD as a new flat panel display. The present investigationaims at undemtanding the photoluminescence and cathodoluminescent properties of hGaO$_3$: $Eu^{3+}$ phosphor bytaking into account the possibility that this phosphor could be applied for FED. In onler to investigate on.sucha detailed behavior; 8everM experimental skil18 Je conducted to the LaGaO$_3$:$Eu^{3+}$ phosphoL The excimtion srectrum artd emission spectmn were rnezsured in the UV range and then decay curve of $^5D_0$+$^7F_j$transitions\vas examined. The decay behavior of $^5D_0$ emission was anMyzed by a newly Iuoposed cross-relaxation mech-ani8In in asswiation with inteFwnter di1ffision (or migration). The cross-mlaxation from $^5D_0$ to CTB (Cha'geTransfer Band) wuld be a quite retsonable by considering the excitation spectrum. It could be also found thatthe quenching type was changed from ditfrsion controlled process to the direct quenching process -s inJeasing $Eu^{3+}$ oncntration.

• Phonetics and Speech Sciences
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• v.12 no.2
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• pp.39-49
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• 2020

The prosody of children with autism spectrum disorders (ASD) has several abnormal features, including monotonous speech. The purpose of this study was to compare acoustic features between an ASD group and a typically developing (TD) group and within the ASD group. The study also examined audience perceptions of the lengthening effect of increasing the number of syllables. 50 participants were divided into two groups (20 with ASD and 30 TD), and they were asked to imitate a total of 28 sentences. In the auditory-perceptual evaluation, seven participants chose sentence types in 115 sentences. Pitch, intensity, speech rate, and pitch slope were used to analyze the significant differences. In conclusion, the ASD group showed higher pitch and intensity and a lower overall speaking rate than the TD group. Moreover, there were significant differences in s2 slope of interrogative sentences. Finally, based on the auditory-perceptual evaluation, only 4.3% of interrogative sentences produced by participants with ASD were perceived as declarative sentences. The cause of this abnormal prosody has not been clearly identified; however, pragmatic ability and other characteristics of autism are related to ASD prosody. This study identified prosodic ASD patterns and suggested the need to develop treatments to improve prosody.

• Journal of Navigation and Port Research
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• v.37 no.4
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• pp.401-407
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• 2013

In parallel with the development of ship equipment, bridge systems have been improved, but marine accidents due to human error have not been reduced. Recently, research in nautical bridge equipment has focused on suitable ergonomic designs in order to reduce these errors due to human factors. In a bridge of a ship, there are numerous auditory signals that deliver important information clearly to the sailors. However, only a few studies have been conducted related to the human recognition of these auditory signals. There are three types of auditory signals: voice alarms, abstract sounds, and auditory icons. This study was conducted in order to design more appropriate auditory icons using a sensibility evaluation method. The auditory icons were rated to have five warning situations (engine failure, fire, steering failure, low power, and collision) using the Semantic Differential Method. It is expected that the results of this study will be used as basic data for auditory displays inside bridges and for integrated bridge alarm systems.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.116-116
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• 2007

21 세기에 접어들면서 인터넷을 통한 정보 통신의 발달과 개인 휴대용 이동 통신기기의 활발한 보급에 따라 휴대형 전자기기들의 소형화와 고성능화로 나아가고 있다. 이러한 전자기기에 사용될 IC의 내장 메모리 또한 집적화 및 고속화, 저 전력화가 이루어져야 한다. 이러한 전자기기들에 필수적인 압전 세라믹스 부품 중 압전 부저 및 기타 음향 부품등을 각종 전자기기와 무선 전화기에 채택함으로써 압전 부품에 대한 수요와 생산이 계속 증가할 것으로 전망된다. 이처럼 압전 세라믹스를 이용한 그 응용 범위는 대단히 방대하며, 현재 모든 압전 부품들은 PZT 계열 재료로 만들어지고 있고, 차후 모두 비납계열 재료로 대체될 것이 확실시된다. Pb의 환경오염은 이미 오래전부터 큰 문제점으로 인식되고 있었으며 그 일례로 미국의 캘리포니아 주에서는 1986년부터 약 800종의 유해물질, 그 중에서도 Pb 사용을 300ppm 이하로 규제하는 Proposition 65를 제정하여 실행하고 있다. 그리고 2003년 2월에 EU (European Union) 에서 발표한 전자산업에 관한 규제 사항중 하나인 위험물질 사용에 관한 지칭 (Restriction of Hazardous Substance, RoHS) 에 의하면, 2006 년 7월부터 전기 전자 제품에 있어서 위험 물질인 Pb을 포함한 중금속 물질(카드늄, 수은, 6가 크롬, 브롬계 난연재)의 사용을 금지한다고 발표하였다. 비록 전자세라믹 부품에 함유된 Pb는 예외 사항으로 두었지만 대체 가능한 물질이 개발되면 전자세라믹 부품에서도 Pb의 사용을 금지한다고 규정하였다. 더욱이 일본은 2005 년부터 Pb 사용을 금지시켰다. 이와 같이 Pb가 환경에 미치는 영향 때문에 비납계 강유전 물질 및 압전 세라믹스 재료에 대한 연구가 전 세계적으로 활발히 진행되고 있다. 본 연구에서는 비납계 강유전체의 patterning을 위해서, NKN 박막을 고밀도 플라즈마원인 ICP를 이용하여 식각 mechanism을 연구하고, 식각변수에 따른 식각 공정을 최적화에 대하여 연구하였다. 가스 혼합비에 따라 식각 할때 700 W의 RF 전력과 - 150 V의 직류 바이어스 전압을 인가하였고, 공정 압력은 2 Pa, 기판 온도는 $23^{\circ}C$로 고정하였다. 식각 속도는 Tencor사의 Alpha-step 500을 이용하여 측정되었으며 식각 시 NKN 박막 표면과 라디칼과의 화학적인 반응을 분석하고 식각 메커니즘을 규명하기 위하여 XPS(x-ray photoelectron spectroscopy)를 사용하였다.

• Korean Journal of Optics and Photonics
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• v.28 no.5
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• pp.236-240
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• 2017

In this paper, we investigate the thermal response of skin tissue to high-intensity focused ultrasound (HIFU) by means of infrared (IR) thermal imaging. For skin tightening, a 7-MHz ultrasound transducer is used to induce irreversible tissue coagulation in porcine skin. An IR camera is employed to monitor spatiotemporal changes of the temperature in the tissue. The maximum temperature in the tissue increased linearly with applied energy, up to $90^{\circ}C$. The extent of irreversible tissue coagulation (up to 3.2 mm in width) corresponds well to the spatial distribution of the temperature during HIFU sonication. Histological analysis confirms that the temperature beyond the coagulation threshold (${\sim}65^{\circ}C$) delineates the margin of collagen denaturation in the tissue. IR thermal imaging can be a feasible method for quantifying the degree of thermal coagulation in HIFU-induced skin treatment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.472-482
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• 2019

This paper describes the stabilization of underwater TAS winch system Deploy/Recover operation performance. TAS winch installed on the stern of submarine performs to deploy/recover sensor, towing cable and rope tail which is deployed from the stern and separated from submarine itself. Also TAS winch provides transmission path of power to the sensor and data transmitting/receiving path which data are acquired from underwater environment like sound, depth and temperature. At the step of TAS winch evaluation test, sporadic standstill and rotating speed oscillation phenomenon were occurred. Winch motor provides the available torque to deploy/recover TAS and root cause analysis to the winch motor was done to find exact reason to sporadic malfunction. When winch motor was disassembled, eccentricity of rotor, slip-ring and the other composition part for winch motor were found. These might cause magnetic field distortion. To make TAS winch system more stable and block magnetic field distortion, this paper suggests methods to enhance fixing status installed in winch motor. For reliable data acquisition for TAS winch operation, the deploy/recover function of the improved type of TAS winch was verified in LBTS making similar condition with sea status. At the end of stage, improved type of TAS winch was tested on some functions not only deploy/recover function, but sustainability of TAS operation on specific velocity, steering angle of submarine in the sea trial. Improved type of TAS winch was verified in accordance with design requirement. Also, validity of suggested methods were verified by the sea trial.

• Journal of the Korean Geotechnical Society
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• v.24 no.8
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• pp.5-12
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• 2008

Biot proposed the frequency dependent formulation for the propagation of elastic waves in saturated media based on the coupled theory mixtures. Based on Biot theory, a special frequency called 'the characteristic frequency' contains unique information of the permeability of soils. The characteristic frequency is measured from I/Q (inverse quality factor) versus frequency curve by an acoustic sweep test, and the permeability of soils is computed from Biot equation. In this paper, laboratory tests are performed at The University of Mississippi using a large test box. The measured characteristic frequency is consistently obtained at 3500 Hz for mortar sands. The computed permeability of mortar sands based on Biot equation turned out 2.01 $10^{-4}m/sec$, while the permeability from the laboratory constant head test turned out 1.49 $10^{-4}m/sec$. This paper addresses the theoretical background and experimental procedure of this technique.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.539-549
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• 2024

This study employed text mining techniques like frequency analysis, word clouds, and LDA topic modeling to assess consumer satisfaction and dissatisfaction with Hyundai Motor Company in the Chinese market, compared to brands such as Toyota, Volkswagen, Buick, and Geely. Focusing on compact vehicles from these brands between 2021 and 2023, this study analyzed customer reviews. The results indicated Hyundai Avante's positive factors, including a long wheelbase. However, it also highlighted dissatisfaction aspects like Manipulate, engine performance, trunk space, chassis and suspension, safety features, quantity and brand of audio speakers, music membership service, separation band, screen reflection, CarLife, and map services. Addressing these issues could significantly enhance Hyundai's competitiveness in the Chinese market. Previous studies mainly focused on literature research and surveys, which only revealed consumer perceptions limited to the variables set by the researchers. This study, through text mining and comparing various car brands, aims to gain a deeper understanding of market trends and consumer preferences, providing useful information for marketing strategies of Hyundai and other brands in the Chinese market.

• Journal of Popular Narrative
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• v.25 no.4
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• pp.263-288
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• 2019

Barrier-free films enhance accessibility to audiovisual image contents by providing specific information on screen and through sound so that people with vision or hearing loss can receive the same amount of information as those without disabilities and immerse themselves in the audiovisual images. This study pays attention to barrier-free audiovisual contents in relation to the cultural civil rights of people with vision or hearing loss in South Korea. While institutional efforts have been made in the 2010s to improve the access to audiovisual media of people with vision or hearing loss, the goal of enabling people with vision or hearing loss to fully enjoy all audiovisual contents at a level equal to the non-disabled has not yet been realized. Amid the lingering conflict between disabled groups and multiplexes that has lasted years, the global video streaming service Netflix has aggressively threatened the dominance of local multiplexes with the launch of its Korean service. As Netflix, which is subject to U.S. regulations guaranteeing the rights of people with vision or hearing loss, has produced original dramas and movies involving Korean production teams, the cultural civil rights discourse of the disabled has transitioned to the issue of the rights of cultural consumers crossing national borders in the era of globalization. Changes in the media environment raise the issue of civil rights guarantees in which disabled people enjoy the right to simultaneously watch movies and comment on movies by participating in a common discourse, equally with non-disabled people. The "right to be part of the audience for Korean cinema" for Korean deaf people, which has long been neglected, should also be considered as a cultural civil right that crosses the boundaries of language, nation and disabilities. This essay examines the current issues surrounding the right to cultural entertainment of people with vision or hearing loss in South Korea in conjunction with the contemporary trend of rapid changes in the media environment and the global spread of the movement for cultural civil rights of people with disabilities, and suggests the need for visual culture studies to take a serious step toward disability studies.

• Cartoon and Animation Studies
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• s.22
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• pp.81-97
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• 2011

The technology of 'Virtual Reality' has placed in advanced tools for human beings' joy and anger together with sorrow and pleasure in our generation. It has recently tried in a variety ways to use as an implication for treatment in the field of Cognitive Psychology. Especially, it widely approaches to human in terms of that a sense of reality in a virtual world through the five senses should reinterpret the meaning of cognition in the real world. Based on this paradigm shift, it allows for new treatment using the technology of virtual reality. A typical example is a field of Therapy in order to overcome panic disorder. It has advantages that in particular development of flexible interaction technologies in a virtual space can lead patients to experience psychological environments rather than physical one. the interaction technology provides environments in which users' five senses can be actively stimulated, it is very useful that information from the experiences in the virtual world allows people to learn through real experiences by renewing potential energies, advantages of Virtual Reality Therapy can be customized treatment by depending on symptoms in patients with panic disorder and are capable of differentiate application for the cure at each stage. It is to treat by leading patients to get accustomed to environments and situations in real world through care process with each symptom and stage. It is helpful that based on A Human-Sensibility Ergonomics, technologies like immersive virtual reality equipment, force-relative feedback and stereophonic sound, and like stimulating the sense of smell make people to induce experiences by stimulating human's five senses. There are many advantages of immersion in virtual world in that the phenomenon such as challenge, interaction, reality, illusion, and cooperation is expanded. As an application for therapy by growing such augmented reality, virtual space and sharing of data through the Internet and also inexpensive its availability have recently expanded the base. There are other benefits of Virtual Reality Therapy offering active interaction environments for cognitive experience which can provide appropriately adjusted environments for patients who are hard to overcome the real situation because of phobia. In addition to that it is safe and economical and patients' confidentiality is assured. Moreover, due to the principles of applying real-time navigation the Virtual Reality Therapy makes modification and supplementation easier and also it can reduce cybersickness because of the supply of Lenticular allowing people to see stereoscopy without eyeglasses, which makes sense of presence clearer. On top of that due to the development of interactive technologies, it is becoming close to sense of reality similar to real world by leading users to navigate by themselves and to operate objects in a virtual space. This paper will therefore examine, although it is of limited, characteristics of application of virtual reality technology based on A Human-Sensibility Ergonomics used for treatment for a disorder. this paper will analyse a range of its application and problems and it will suggest the future possibilities.