• 센서학회지
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• 제24권6호
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• pp.373-378
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• 2015

The structure of the human ear is divided into the outer ear, the middle ear, and the inner ear. The inner ear includes the cochlea that plays a very important role in hearing. Recently, the development of an artificial cochlear device for the hearing impaired with cochlear damage has been actively researched. Research has been carried out on the biomimetic piezoelectric thin film ABM (Artificial Basilar Membrane) in particular. In an effort to improve the frequency separation performance of the existing piezoelectric thin film ABM, this paper presents the design, fabrication, and characterization of the production and performance of a partially etched-type ABM material. $O_2$ plasma etching equipment was used to partially etch a piezoelectric thin film ABM to make it more flexible. The mechanical-behavior characterization of the manufactured partially etched-type ABM showed that the overall separation frequency range shifted to a lower frequency range more suitable for audible frequency bandwidths and it displayed an improved frequency separation performance. In addition, the maximum magnitude of the vibration displacement at the first local resonant frequency was enhanced by three times from 38 nm to 112 nm. It is expected that the newly designed, partially etched-type ABM will improve the issue of cross-talk between nearby electrodes and that the manufactured partially etched-type ABM will be utilized for next-generation ABM research.

• 한국정보통신학회논문지
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• 제12권5호
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• pp.937-941
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• 2008

수화는 청각 장애인에게 있어 중요한 의사소통 수단이며, 청각 장애인들은 수화를 통해 대인관계를 넓히며 또한 불편함 없는 일상생활이 가능하다. 그러나 최근 인터넷 통신의 발전으로 증가하고 있는 많은 화상 채팅 및 화상 통화서비스에서는 건청인과 청각 장애인 사이에 통역을 하는 시스템이 없어 청각 장애인들이 불편을 겪고 있다. 본 논문에서는 이러한 문제점을 해결하기 위하여 수화 인식기법을 제안하였다. 제안된 기법에서는 화상 카메라를 통해 얻어진 영상에서 각각 RGB, YUV, HSI 색상 정보를 이용하여 두 손의 위치를 추적하여 잡음을 제거 한 후, 두 손의 영역을 추출한다. 추출된 손의 영역은 잡음과 훼손에 강한 ART2 알고리즘을 이용하여 학습한 후 인식한다. 본 논문에서 제안된 수화 인식 방법을 실험한 결과, 수화에 사용된 지 숫자 1부터 10을 효율적으로 인식하는 것을 확인하였다.

• 동의생리병리학회지
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• 제20권6호
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• pp.1524-1529
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• 2006

The fruits of Cornus officinalis have been used in traditional Oriental medicine for treatment of inner ear diseases, such as tinnitus and hearing loss. In the present study, we showed that the ursolic acid obtained from Corni fructus protected HEI-OC1 auditory cells from hydrogen peroxide cytotoxicity in a dose-dependent fashion. In addition, to investigate the protection mechanism of ursolic acid on hydrogen peroxide cytotoxicity toward HEI-OC1, we measured the effects of ursolic acid on lipid peroxidation and activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) in hydrogen peroxide treated cells. Ursolic acid (0.05 - 2 ${\mu}g/ml$) had protective effect against the hydrogen peroxide-induced HEI-OC1 cell damage and reduced lipid peroxidation in a dose-dependent manner. Pre-treatment with ursolic acid significantly attenuated the decrease in activities of CAT and GPX, but SOD activity was not affected by the ursolic acid or hydrogen peroxide. These results indicate that ursolic acid protects hydrogen peroxide-induced HEI-OC1 cell damage through inhibition of lipid peroxidation and induce the antioxidant enzymes CAT and GPX.

• 치위생과학회지
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• 제15권5호
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• pp.603-611
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• 2015

치과 진료실에서 발생하는 소음원에 대한 소음의 특성을 파악하고 그에 따른 피해 가능성을 알아보기 위해 휴대용 소음기로 측정하여 검토한 결과 다음과 같은 결론을 얻었다. 치과용 의료기기 소음측정 결과 단독측정에서는 고속 핸드피스가 가장 높았으며, 초음파 스케일러, 저속 핸드피스 순서로 낮게 나타났다. 단독측정 시 평균 소음도는 58~66 dB(A)를 보였으며, 복합측정 시 평균 소음도는 62~71 dB(A)를 보였다. 진료실 형태에 따른 개방형과 개실형의 소음측정 결과 개방형 진료실에서의 소음이 평균 1.9~3.2 dB(A) 더 높게 나타났다. 비진료 시와 진료 시의 소음측정 결과 초음파 스케일러와 고속 핸드피스의 소음에서 통계적으로 유의한 차이가 있었다. 초음파 스케일러와 high volume aspirator을 함께 사용하였을 때 가장 높은 소음도를 보였으며, 진료 시 75.5 dB(A)로 비진료 시와 3.5 dB(A)의 소음차를 보이며 더 높게 나타났다. NR 곡선으로 진료 시 가장 높은 소음도를 보인 치석제거를 평가해본 결과 치석제거 시 NR-73~78로 ISO 소음기준중 일반작업장의 소음기준을 초과하는 수준이며 8 kHz의 고주파에서 피크치를 나타냈다. 진료 시 거리에 따른 소음을 측정한 결과 작업자와 가까운 30 cm 거리에서의 소음이 100 cm 거리에서의 소음보다 높은 패턴을 보였으며, 30 cm 거리에서 대상 치과 의료기기에서 발생하는 소음레벨은 79.8~80.6 dB(A)으로 장시간 폭로 시 청력 손실을 초래할 수 있는 수준이다. 두 거리의 차이로 5 dB(A) 이상의 소음 감쇠 효과를 확인하였다. 이상의 결과를 종합하여 볼 때 치과 치료 시 진료실 소음은 치과 의료기관 종사자에게 정신적, 육체적 피해를 줄 수 있는 정도이며, 본 연구결과를 통하여 얻어진 자료들이 기초가 되어 더 많은 치과 진료 시의 소음에 대한 특성이 파악된다면 직장환경의 질을 높이기 위한 체계적인 소음 감소 대책 수립이 가능할 것으로 생각된다.

• International Journal of Computer Science & Network Security
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• 제22권11호
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• pp.157-162
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• 2022

Cerebral palsy is one of the most serious forms of disorders of the psychophysical development of children, which manifests itself in disturbances of motor functions, which are often combined with speech disorders, other complications of the formation of higher mental functions, and often with a decrease in intelligence. The article will discuss the speech disorder in children with cerebral palsy. Emphasis is placed on some important aspects, which should bear in mind, investigating the problem of specifics of speech development of children with cerebral palsy. In particular at the heart of speech disorders in the cerebral palsy is not only damage to certain structures of the brain, but also the later formation or underdevelopment of those parts of the cerebral cortex, which are of major importance in linguistic and mental activity. This is an ontogenetically young region of the cerebral cortex, which is most rapidly developing after birth (premotor, frontal, temmono-temporal). It is important to take into account, that children with cerebral palsy have disturbances of phonemic perception. Often, children do not distinguish between hearing sounds, cannot repeat component rows, allocate sounds in words. At dysarthria, there are violations of pronunciation of vowel and consonant sounds, tempo of speech, modulation of voice, breathing, phonation, as well as asynchronous breathing, alignment and articulation. As a result, we identified the main features and specifics of the speech development of children with cerebral palsy and described the conditions necessary for the full development of language. Language disturbances in children's cerebral palsy depend on the localization and severity of brain damage. Great importance in the mechanism of speech disorders has a pathology that limits the ability of movement and knowledge of the world.

• 대한환경공학회지
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• 제33권10호
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• pp.748-755
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• 2011

1960년대 산업화 이후 기계화가 가속되어 산업발달에 많은 기여를 하였으나 고소음 작업장에서 발생하는 소음피해에 대한 대책은 거의 없는 실정이다. 특히 공장 및 작업장에서 발생하는 기계소음은 반복적으로 되풀이되어 충격적이며, 강한 소음으로 대부분의 현장 작업자들은 높은 불쾌감과 청력장애의 위험을 부담하고 있다. 이러한 관점에서 이 연구는 고소음 작업장에서 발생하는 작업기계 소음을 평가하기 위한 적정 평가어휘를 추출하고자 했으며, 이렇게 추출된 어휘는 작업 기계소음을 평가하기 위한 음향심리 실험 및 기계소음 규제기준 설정을 위한 유용한 자료로 활용될 수 있을 것으로 사료된다.

• KIEAE Journal
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• 제14권4호
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• pp.69-79
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• 2014

Adverse effects resulting from the development of the environment and to minimize damage to the natural environment and the desire for pleasant scenery and the sense of raising more awareness about May 17, 2007 in accordance with the scenery method is established by each municipality landscape management and landscape planning committee Configure the district planning officer for development projects, including enhancing deliberation scenery method 7 February 2014 and revised in urban areas is more than $30,000m^2$ urban planning landscape projects are all considered by a committee mandated to landscape receive a defined landscape plan for the development was enhanced. Gyeonggi Province in 2007 after the enactment of the scenery method for district planning and landscape planning by strengthening the district planning consideration during deliberations landscape simulation by selecting the view that the proposed mandatory hearing officer from the Joint Committee on Urban construction was done. In this study, Gyeonggi-do district planning business point of view the characteristics of the landscape planning and landscape planning of the center of analysis and as a basis for the evaluation presented.

• 한국보건간호학회지
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• 제9권2호
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• pp.43-51
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• 1995

Many poeple has been engaged in industry is aware of the dangers from exposure to high intensity nose levels. The exposure to high intensity noise is encountered in a large number of situations. Laws governing the safety and health of employed people being to create a suitable working environment and eliminate unsafety practices and processes. Work areas should be designed and laid out so that they are satisfactory both from the environmental and safety points of view. In this connection safety also implies that noise is kept at a level which is not likety to cause hearing damage. This study was performed to measure the noise of press and assembly process in an automobile factory. and suggested the method of noise control. Consequently the effect ways of reducing level in working environment are as follows; 1. Changes to machines which would reduce noise generation. 2. Alteration of equipment to avoid impact in machinery and handing materials. 3. Enclosure of noisy machines or machine parts. 4. Mounting of attenuators on gas and air outlets as well as ventilation ducts. 5. Erection of sound absorbing screens. linings. and baffles in work areas. 6. The personal ear protectors can be chosen to protect the workers.

• 한국컴퓨터정보학회논문지
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• 제23권12호
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• pp.163-170
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• 2018

This study was conducted to investigate the effects of noise from dental clinics on workers and to establish a reduction plan. The noise generated by the treatment instrument(Ultrasonic scaler, Hand piece, 3-way syringe, Suction, Compressor) was measured in order to determine the characteristics(level, frequency) of the noise during medical treatment(Oral prophylaxis, Conservation treatment, Prosthesis treatment, Implant Scaling, Tooth eliminating). We also assessed the noise levels in dental clinic using evaluation indicators such as NR-curves and NRN. The results of the analysis showed that the noise generated during the treatment was 85dB(A) ~ 70dB(A) and that the high frequency component was dominant, which would affect the workers working at the dental clinic. The NR-curve analysis showed NR-67 to NR-83 and the high frequency components of 4kHz to 8kHz were predominant and far exceeded noise levels in the workplace. To minimize the noise damage of workers and to provide high quality medical service, it is necessary to establish countermeasures such as wearing a soundproof and periodic hearing tests.

• 대한후두음성언어의학회지
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• 제31권2호
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• pp.49-55
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• 2020

Evaluating the patient's voice before thyroidectomy is useful for the purpose of identifying patients with vocal cord paralysis without symptoms, identifying other patient's voice abnormalities, and whether it is related to voice disorders that may occur after surgery. Also voice evaluation after thyroid surgery is helpful in diagnosis, treatment, and rehabilitation and follow-up of voice disorders that occur without clear nerve damage after thyroidectomy. And it is helpful for rapid recovery through active early rehabilitation treatment for patients who complain of speech impairment without paralysis. In particular, neck exercise can improve the adhesion of the surgical site and increase the range of motion of the neck as well as improve subjective neck discomfort. In addition, hearing, voice and breathing functions should be improved, and voice hygiene education and counseling should be provided. Vocal cord injection is the first treatment option for unilateral vocal cord palsy. By establishing a protocol for voice disorders before and after thyroid surgery and providing appropriate treatment, the quality of life of patients can be improved.