• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.554-554
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• 2013

대기압 제트 플라즈마를 저주파(수-수십 kHz) 전압에서 구동 시, 일반적으로 '스트리머(streamer)'혹은 '플라즈마 총알(plasma bullet)'로 불리는 현상이 특정 운전조건에서 관찰된다. 본 연구에서는 동일 구조의 Ta, Ti, stainless steel, brass, Cu, Ni 전극을 이용하여 전극물질에 따른 대기압 제트 플라즈마의 특성 변화를 분석하였다. 각각의 물질은 서로 다른 이차전자방출계수, 일함수, 전기전도도 등 고유한 성질이 다르기 때문에 이들 전극을 이용하여 발생시킨 제트 플라즈마 역시 다른 특성을 갖는다. Acton SpectroPro750 분광기를 이용하여 얻은 플라즈마 방출광스펙트럼으로부터 구한 전자 여기온도(Texc=680~720 K)와 OH의 분자 회전온도(Trot=350~380K)는 물질에 따라 큰 변화를 보이지 않았으나, 발생된 스트리머 거동에서 큰 차이를 확인하였다. ICCD 카메라를 이용한 시간 분해된 이미지에서 전극물질에 따른 첫 번째 스트리머의 발생시간 및 스트리머 속력, 두 번째 스트리머의 분리시간이 모두 다른 것을 확인하였다. 제일 차이가 심하게 나타나는 Ti과 Cu의 경우 첫 스트리머의 발생시간 차이는 약 $1{\mu}s$이며, 평균속력 및 순간속력이 약 2 km/s 차이가 났다. 이 결과를 통해 물질의 이차전자방출계수 및 일함수가 대기압 제트 플라즈마에서 스트리머 발생에 영향을 주는 것을 알았고, 다른 전극물질을 사용한 제트 플라즈마의 특성이 다름에 따라 여러 응용에서의 결과에도 영향을 미칠 것이라생각한다.

• Journal of the Ergonomics Society of Korea
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• v.15 no.1
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• pp.79-90
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• 1996

A research project was conducted to assess the levels of noise exposed to "Noraebang" users and potential hazards to noise-induced hearing loss due to commercial Noraebang noise. A two-way, mixed-factors factorial design was employed for the experiment using independent variables of "noise source" (no- singer, 1-singer, and 2-singer conditions) and "music type" (Trot, Ballad, and Rock music) with 18 normal hearing subjects. Each singer group sang 5 popular songs of each music type in each signing condition, whereas background music was just played for the no-singer condition. For each music played/sung, equivalent continuous sound pressure levels and maximum sound pressure levels were measured for data analysis purposes. Pure-tone audiometry was applied for measuring subjects' hearing threshold levels before and after exposure to Noraebgang noise. The statistical analyses indicate that average continuous noise levels due to Noraebang leisure environment were very serious, especially when two people were singing (higher than 95 dBA). Furthermore, maximum noise levels often exceeded the OSHA's non-premissible 115 dBA level. Worse yet, hearing loss assessment implies that Noraebang facilities may pose a serious threat to noise-induced hearing loss, based on 6-8 dB loss at 125 Hz and 8 dB loss at 4000 Hz after about 1-hour Noraebang noise exposure.

• The Journal of Korea Robotics Society
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• v.18 no.2
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• pp.172-181
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• 2023

This paper presents research on the stability of control for a quadruped robot with two different leg structure designs. The focus of the research is on the design and analysis of the leg structures in terms of their impact on the stability and robustness of the robot's motion. First, a static analysis was performed in the simulation to compare the structural strength of the legs when the same force was applied. Secondly, two quadruped robots were built, each equipped with differently designed legs, and performed trot gait walking in the real world. And the states of the robots and the torques of each joint were analyzed and compared. In conclusion, based on the results of structural analysis in simulation and the actual walking experiments with the robots, it was demonstrated that the legs designed to be structurally robust improved the control stability of the quadruped robot.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.8
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• pp.264-273
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• 2013

The importance of the robots has emerged as the means of minimizing the casualties in the future war, and, thus, the biomimetic robots mimicking the optimized organisms has been actively studied. The robot inspired lizard is suitable for reconnaissance and the surveillance in narrow areas. In this paper, we analyzed the locomotion of a lizard by motion capture system using the infrared markers. We attached 21 markers to the joints of the lizard. By considering the measured data, we analyzed the walking motion of the lizard which trots in a sprawled posture. Moreover, we proposed the 25 dof kinematic model which was able to reproduce the gait of the lizard faithfully. The model was verified by simulations.

• Journal of Korean society of Dental Hygiene
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• v.17 no.3
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• pp.395-404
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• 2017

Objectives: The purpose of this study was to identify the effects of music intervention on the patient's fear and anxiety during scaling. Methods: 360 patients who had visited W University dental hygiene laboratory were selected as study subjects and divided into experiment group and control group. Results: Study results showed that the control group (71.9%) and the experimental group (75.1%) had experiences avoiding dental treatment due to fear. In the control group (37.6%) and experimental group (40.6%), the highest influencing factor was the sound of machine and followed by pain. The experimental group preferred classical music, followed by pop songs, trot music and instrumental music. In the experimental group (83.3%), fear and anxiety were alleviated by music, and 77.9% of the patients mentioned they would recommend music for scaling to other patients. There was an interaction effect (p=0.014) between the groups before and after the measurement of the lowest blood pressure. There was a significant difference in pulse before and after pulse measurement (p=0.000). There was a significant difference in respiration between groups (p=0.042) and before and after respiration (p=0.030). Conclusions: Study results showed that music intervention that utilizes music during scaling showed significant effects on the alleviation of fear and anxiety, affecting Pulse number among vital signs. Therefore, more systematic program is to be required to alleviate dental fear and anxiety with music therapy not only for scaling, but also for dental clinic in the future.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.204-207
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• 2005

Until present, most studies about energy efficiency of quadruped walking robot are mathematical modelings, dynamic analysis or simulation consumption energy per period by basic efficiency evaluate in this paper, a quadruped walking robot Titan-VIII is used for walking experience. The total moving length is about 2[m]. The stride length is 0.1, 0.2, 0.3, walking period is changed by 1.0, 1.5, 2.0, 3.0[sec] per each stride length. So consumption energy of 12 cases are measured. The energy efficiency of quadruped walking robot was analyzed by data that is saved by an experiment.

• The Korean Journal of Nuclear Medicine Technology
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• v.28 no.1
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• pp.31-33
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• 2024

Purpose: Music therapy helps alleviate anxiety, depression, and pain for cancer patients, contributing to stress relief. With such advantages, music therapy is applied across a broad spectrum of treatment areas, including mental disorders, developmental disabilities, and conditions affecting the elderly. It has been shown to enhance the quality of life for terminally ill cancer patients. Recent research has revealed its positive effects in boosting immune function and resilience. In light of these findings, the author conducted a study to investigate patient satisfaction with music listening. Materials and Methods: First, a survey was conducted with 30 individuals to inquire about the perceived necessity of listening to music in a waiting area. Next, participants were asked whether listening to music could contribute to psychological stability. Finally, preferences for music genres and satisfaction with music listening were assessed with a sample of 20 individuals. Results: In terms of the perceived necessity of listening to music in the waiting area, 28 out of 30 individuals, or 93%, expressed agreement. Regarding the belief that music listening could contribute to psychological stability, 28 out of 30 individuals, or 93%, believed that it would indeed help with stability. When it comes to preferred music genres, 4 individuals (13%) favored classical music, 2 individuals (6%) preferred traditional Korean music, 2 individuals (6%) enjoyed trot music, and 20 individuals (66%) had no specific genre preference. As for music listening satisfaction, 17 out of 20 individuals, or 85%, reported being satisfied. Conclusion: When patients visit the hospital, stress can increase due to concerns about their medical conditions. To address this, providing a variety of music genres at the hospital has been effective in reducing patient stress and promoting psychological stability.

• Journal of Veterinary Clinics
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• v.22 no.1
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• pp.21-25
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• 2005

This study was performed to assess therapeutic effect of the tibial plateau leveling osteotomy (TPLO) in dogs with experimentally transected cranial cruciate ligaments (CrCL). Nine healthy adult Beagle dogs were transected left CrCL under general anesthesia. The dogs were assigned to TPLO and non-TPLO control groups. The TPLO procedures for correcting the CrCL rupture in the left stifle of dogs were performed under sterile conditions. Before TPLO procedures, all dogs were screened by orthopedic and radiographic examinations. Dogs were lameness free for the previous three months, and when examined at the walk and trot on a hard surface, in a straight line and on a circle. Lateral and craniocaudal radiographs were done to confirm the soundness of the both knee joint in dogs and not detectable lesions were diagnosed. The dogs were intravenously injected with a 10 mci/kg of 99mTechnetium-methylene diphosphonate (99mTc-MDP) under general anesthesia. Scintigraphs were obtained using a large field of view gamma camera equipped a parallel-hole, low-energy about 3 hours after intravenous injection of 99mTc-MDP. Before CrCL transection and 4, 8, and 12 weeks after the procedures, scintigraphy were conducted. Bone uptake of the left stifle joint increased after the procedures in all dogs. When the bone uptake from the TPLO procedure was compared with that of the control, there was a significant difference (p < 0.05). At 12 weeks after the TPLO procedure, the dogs showed normal anatomical posture and gait. It is concluded that TPLO procedure was effective in reconstruct of the stifle joint in dogs with CrCL rupture.

• Journal of Navigation and Port Research
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• v.37 no.6
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• pp.617-625
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• 2013

"Sale and purchase brokers" are independent contractors who act as agents for principals intending to seller or buy ships in English Maritime Law. The essential feature is that legal position of shipbroker is largely one of agency. They can be obtained by a study of the Lloyd's Register or the equivalent registers of other Classification Societies, the American Bureau of Shipping and Korean Registers. Such a broker is of valuable assistance to the prospective seller or purchaser. And the broker's liability normally arises in the context of a contract. But, expressed in general terms, those contractual obligations are, in absence of contrary agreement, to act with reasonable care and skilled to obtain the cover requested by his client not to guarantee that such will be concluded and to ensure that the scope of the policy, its essential terms and relevant exclusions are made known to the insured. Acting in this professional capacity, the broker's liability are such that the facts upon which an action for breach of contract may be based may also found an action for the trot of negligence provided that there is shown to be the necessary 'assumption of responsibility' by the broker conveyed directly or indirectly to the insured. This thesis deals with liability of S&P Brokers, the legal problems of ship broking, commission, conflicts of interest and secret commissions in English Maritime Law and the Cases.

• Journal of Service Research and Studies
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• v.13 no.1
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• pp.48-62
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• 2023

As seen in the recent K-pop craze, the size and influence of the Korean music industry is growing even bigger. At least 6,000 songs are released a year in the Korean music market, but not many can be said to have been successful. Many studies and attempts are being made to identify the factors that make the hit music. Commercial factors such as media exposure and promotion as well as the quality of music play an important role in the commercial success of music. Recently, there have been many marketing campaigns using Internet memes in the pop music industry, and Internet memes are activities or trends that spread in various forms, such as images and videos, as cultural units that spread among people. Depending on the Internet environment and the characteristics of digital communication, contents are expanded and reproduced in the form of various memes, which causes a greater response to consumers. Previously, the phenomenon of Internet memes has occurred naturally, but artists who are aware of the marketing effects have recently used it as an element of marketing. In this paper, the mediated effect of Internet memes in relation to the success factors of popular music was analyzed, and a prediction model reflecting them was proposed. As a result of the analysis, the factors with the mediated effect of 'cover effect' and 'challenge effect' were the same. Among the internal success factors, there were mediated effects in "Singer Recognition," the genres of "POP, Dance, Ballad, Trot and Electronica," and among the external success factors, mediated effects in "Planning Company Capacity," "The Number of Music Broadcasting Programs," and "The Number of News Articles." Predictive models reflecting cover effects and challenge effects showed F1-score at 0.6889 and 0.7692, respectively. This study is meaningful in that it has collected and analyzed actual chart data and presented commercial directions that can be used in practice, and found that there are many success factors of popular music and the mediating effects of Internet memes.