• Journal of Biomedical Engineering Research
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• v.26 no.5
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• pp.309-317
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• 2005

It is expected that fully-implantable middle-ear hearing devices (FIMEHDs) will soon be available with the advantages of complete concealment, easy surgical implantation, and low power operation to resolve the problems of semi-implantable middle-ear hearing devices (SIMEHDs) such as discomfort of wearing an external device and replacement of battery. Over the last 3 years, a Korean research team at Kyungpook National University has developed an FIMEHD called ACRHS-1 based on a differential floating mass transducer (DFMT). The main research focus was functional improvement, the establishment of easy surgical procedures for implantation, miniaturization, and a low-power operation. Accordingly, this paper reviews the overall system architecture, functions, and experimental results for ACRHS-1 and its related accessories, including a wireless battery charger and remote controller.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.3
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• pp.168-176
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• 2011

Objectives: Hundreds of thousands of call center workers are wearing an acoustic device for their businesses, such as telemarketing and customer counseling, and the number of the workers are increasing sharply. Because call center workers always talk to dozens of customers over the headset, they would be placed under the state of a higher risk with their hearing ability. The purpose of this study is to investigate factors that affect the hearing thresholds for the call center workers. Methods: This study investigated hearing losses of 101 workers of 5 call centers in Korea by executing puretone audiometry and self-administered questionnaires. A cross table analysis was processed to compare gender differences between male and female. Male and female hearing thresholds were compared with the Students' t-test, and one-way ANOVA was conducted to observe the difference between non-occupational and occupational characteristics in 2, 3, 4, 6, and 8 kHz hearing thresholds for the female workers. Additionally, multiple regression analysis was conducted to find the factors that affect the 4 kHz hearing thresholds. Results and Conclusions: Male hearing thresholds were higher than those of female except for 8 kHz. In the group having an ear related disease, hearing threshold of male left ear was highly affected rather than that of female in 4 kHz. There were significant differences in the variables of alcohol drinking (2 kHz) and headset volume (8 kHz) in both ears. While this study does not show any significant factors that affect the hearing thresholds in the occupational characteristics, the gender and the previous ear related diseases, non-occupational characteristics, were found as the factors in 4 kHz. It is suggested that the more detailed survey be performed to identify the occupational factors that affect the hearing thresholds in the call center workers based on the result derived from this study.

• Archives of Plastic Surgery
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• v.46 no.6
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• pp.525-534
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• 2019

Background In microtia patients with bilateral hearing impairment, hearing improvement is crucial for language development and performance. External auditory canal reconstruction (EACR) has been performed to improve hearing, but often results in complications. We performed transcutaneous bone conduction implant (TBCI) surgery in these patients. This study aimed to evaluate the safety and efficacy of TBCI surgery. Methods A retrospective review was performed of five patients who underwent auricular reconstruction and TBCI surgery and 12 patients who underwent EACR between March 2007 and August 2018. Hearing improvement was measured based on the air-bone gap values using pure-tone audiometry over a 6-week postoperative period. We reviewed other studies on hearing improvement using EACR and compared the findings with our results. The surgical techniques for TBCI were reviewed through case analyses. Results Postoperative hearing outcomes showed a significant improvement, with a mean gain of 34.1 dB in the TBCI cohort and 14.1 dB in the EACR cohort. Both gains were statistically significant; however, the TBCI cohort showed much larger gains. Only three of the 12 patients who underwent EACR achieved hearing gains of more than 20 dB, which is consistent with previous studies. All patients who underwent TBCI surgery demonstrated hearing gains of more than 20 dB and experienced no device-related complications. Conclusions TBCI is a safe and effective method of promoting hearing gains in microtia patients with bilateral hearing impairment. TBCI surgery provided better hearing outcomes than EACR and could be performed along with various auricular reconstruction techniques using virgin mastoid skin.

• Physical Therapy Korea
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• v.13 no.1
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• pp.9-15
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• 2006

Work-related musculoskeletal disorder has been associated with long hours of computer work and prolonged periods of static posture. In clinical settings, postural correction is a common treatment approach for individuals with neck, shoulder, and back pain. This study was designed to identify the effect of Forward Head Posture Correctional Device during computer work. Twelve healthy adults (mean age, 27.4 yrs; mean height, 165.0cm mean weight, 65.8 kg) participated in the study. They had no medical history of neurological or surgical problems with their upper extremity. The subjects were asked to perform Head Forward Posture under the guidance of physical therapists and the measured angles were analyzed using a 3-D motion analysis system. Markers were placed on the C7 spinous process, tragus of the ear and forward head angle was between the line from the tragus to the C7 line and the Y-axis at the C7. The statistical significance of difference between, "without" and "with" correctional device was tested by paired t-test. A level of significance was set at ${\alpha}$=.05. In comparison of the computer work between "without" and "with" correctional device, Forward Head Angle was showed significant difference (p<.05). In conclusion, the range of Forward Head Angle was significantly decreased during computer work with the correctional device. Further research is needed to understand the nature of motor control problems in deep muscles in patients with neck, shoulder, and back pain.

• Journal of the Institute of Convergence Signal Processing
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• v.13 no.1
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• pp.1-5
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• 2012

In this study, we constructed a virtual auditory display(VAD) that enables listener to move in a room freely. The VAD system was installed in a soundproof room($4.7m(W){\times}2.8m(D){\times}3.0m(H)$). The system consisted of a personal computer, a sound presentation device, and a three-dimensional ultrasound sensor system. This system acquires listener's location and position from a three-dimension ultrasonic sensor system covering the entire room. Localization was realized by convolving the sound source with head related transfer functions(HRTFs) on personal computer(PC). The calculated result is generated through a LADOMi(Localization Auditory Display with Opened ear-canal for Mixed Reality). The HRTFs used in the experiment were measured for each listener with loudspeakers constantly 1.5m away from the center of the listener' s head in an anechoic room. To evaluate the system performance, we experimented a search task of a sound source position in the condition that the listener is able to move all around the room freely. As a result, the positioning error of presented sound source was within 30cm in average for all listeners.

• Science of Emotion and Sensibility
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• v.13 no.4
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• pp.635-646
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• 2010

This article focuses on Funology and a new classified application system based on concept of language and thought which are formed by body experience. It is defined by Funology Body as that. Funology Body is classifying and searching system which are consisted of a body, world (environment), and device tool. The body is sectioned by Brain, Eyes, Ears, Nose, Mouth, Hand, Torso, Feet, and Heart according as parts of the human body. This allows intuiting and experience searching as making classified system connected to the application relationship with concept of an each part of body. The Brain of the body is sub-classified by Book, Account, Business, Memory, Education, Search, and Aphorism to imply the application with thought. The Eyes take Video, Photography, and Broadcast for visibility. The Ears is categorized as Music, Instrument, Audio, and Radio for hearing. The Nose gets Perfume, Smell for olfactory sense. The Mouth is sectioned by Food, SNS, Chatting, Email, and Blog for eating and communication. The Hand sorts into Games, Kits, and Editing to handle, create, and play. The Torso is grouped by Health, Medical, Dance, Sport, Fashion, and Testyuorself related by protecting internal and meaning of the body core. The Feet is classified by Travel, Transportation, Map, and Outdoor for moving and concept of expanding the terrain. The Heart is consisted of Fear, Anger, Joy, Sadness, Acceptance, Disgust, Expectation, and Surprise for a human feeling. Beyond that, the World takes News, Time, Weather, Map, Fortune, and Shop, and Device tool gets Interface, Utilities. The Funology Body has a unique characteristic of giving intuitive and sensuous pleasure and reflection of users' attitude and taste for changing application flexibly.