• Journal of Preventive Medicine and Public Health
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• v.22 no.3 s.27
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• pp.337-354
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• 1989

In order to evaluate the noisy environment and hearing loss of workers served in noisy working environment, the author investigated 212 manufacturing industries located in Ulsan Industrial District that could be observed for 3 successive years from 1986 to 1988. The obtained results were as follows: 1. There was increased tendency in the number of workers served in noisy working environment and that of examined of hearing loss for three years. 2. In the noise level of working environment, the number of industries less than 89dB(A) was increased every year, while more than 90dB(A) was in decreasing tendency. 3. Mean hearing loss by frequency was the most prominent in 4,000Hz, the level of hearing loss was in increasing tendency yearly, and that of left eat was higher than right ear in almost all type of industry. 4. In 1986, the level of hearing loss by type of industry was highest in manufacture of electric and electronic, and followed by paper and plywood, and metal products in right ear: that was in the order of manufacture of electric and electronic, metal products and textile products in left ear. In 1987, that was in the order of manufacture of metal products, machinery and others in right ear, and metal products, machinery and food stuff in left ear in 1988, manufacture of others, food stuff and machinery in both ear. 5. In hearing loss by service duration, right ear of 5-9 years group was higher than that of less than 5 years in 1987, whereas in 1988, the longer in service duration, the higher in the level of hearing loss in both ear. 6. In 1986, 1987 and 1988, the prevalence rate of noise-induced hearing loss were showed increasing tendency as 0.4% ,0.8% and 1.5% , respectively, and manufacture of textile products was highest(1.0%) in 1986, machinery(1.2%) in 1987 and others(2.8%) in 1988. 7. The proportion of grade E in early loss index were 76.1% (1986), 78.2% (1987) and 80.5% (1988) in left ear, 75.9% (1986), 76.4% (1987) and 75.9% (1988) in right ear.

• Journal of Sensor Science and Technology
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• v.24 no.6
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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.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.5
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• pp.1055-1061
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• 2011

In this study, main parameters: aperture, first bend and second bend which express a structure of ear canal are extracted in order to modeling and manufacture the ready-made ear shells of hearing aids. The proposed parameter extraction method consists of 2 important algorithms, aperture detection and feature detection. In the aperture detection algorithm, aperture of 3-D scanned virtual ear impression and parameters relating to ear shell of hearing aid are determined. The feature detection algorithm detects first bend, second bend, and related parameters. Through these two algorithms, parameters for aperture, first bend, and second bend are extracted to model the ready-made ear shell of hearing aid. The values of these extracted parameters from 36 people's right ear impression are analyzed and measured statistically. As a result of the analysis, it has been found that it is possible to classify ready-made ear shell parameters by age and size. The ready-made ear shell parameters are classified 3-size for 20 years old and 2-size for 60 years olde. Using 3D rhino program, virtual ready-made ear shell is reconstructed by parameters of every type, and simulated to model it. A final product was produced by transferring simulation result with rapid prototyping system. The modeled ready-made ear shell is evaluated with the objective and subjective method. Objective method is the comparison volume ratio and overlapped volume ratio of ear impression from randomly chosen 18 people and ready-made ear shell. And subjective method is that the final product of ready-made ear shell is used by users and the satisfaction number drawn from well fitting and comfortable testing was evaluated. In the result of the evaluation, it has been found that volume ration is 70%, big and middle size ready-made ear shell products are possible, and the satisfaction number is high.

• Korean Journal of Oriental Medicine
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• v.16 no.3
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• pp.115-121
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• 2010

Objectives : Quality control of the needle tips and prevention of pollutions are important factor for safe and effective acupuncture treatment. Ear acupuncture needle is made by 3 companies in Korea, and used to treat for obesity or smoking in clinic frequently, but the Korean industrial Standard is proposed most recently. In spite of the importance, there has been little study about that. Moreover, there was no study about ear acupuncture needle. Methods : We investigated the current condition of needle shape and pollution about the tips and body of the ear acupuncture needle under the stereoscopic microscope. Samples are selected 100 pieces from 300 pieces randomly in each company. Results : The substandard needles are classified into four groups and counted 1. Normal condition (55.3%), 2. Scratch on the surface (14.0%), 3. Malformation of tips (19.3%), 4. Pollution of body (4.3%), 5. Multiple Substandard (7.0%). In the case of including type 2 as a standard needle, normal rate of A company was 81% when B was 76%, and C was 51%. Conclusion : The substandard ear acupuncture needles can induce local side effects such as needling pain or itching. Furthermore, it can disturb the proper effect of acupuncture treatment. We hope that this study can help to improvequality of ear acupuncture and reduce substandard rate for safe and effective ear acupuncture treatment.

• Korean Journal of Computational Design and Engineering
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• v.14 no.2
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• pp.87-95
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• 2009

This paper describes the design of the ossicular replacement prosthesis for the people who have problem of hearing because of middle ear disease. Also the simulation results of the designed product for verification by finite element analysis software (ABAQUS) are presented. New model is applied to middle ear FE analysis which was generated in previous study. The full replacements of ossicular prosthesis for ossicles (malleus, incus and stapes) are made of Hydroxyapatite and Titanium. Although other existing prosthesis models consider only sound amplification effect, current type has damper system which is operating on the audible frequencies. High frequency sound transmitted to inner ear can be reduced and the prosthesis and inner ear can be prevented from damage.

• Korean Journal of Pharmacognosy
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• v.43 no.3
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• pp.243-249
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• 2012

Bee venom (BV), well known as a traditional Oriental medicine, has been widely used in the treatment of some immune-related diseases. However, the anti-allergic effect of BV have not been reported. In this study, we investigated the antiallergic effect of BV on triphasic cutaneous reaction (TpCR) and passive cutaneous anaphylaxis (PCA). Our results indicated that BV suppress ear swelling and vascular permeability on IgE mediated type I hypersensitivity response. Increase in ear thickness was significantly inhibited by BV in this model. BV also blocked the infiltration of immune cells into the ear. Moreover, BV suppressed expression of HDAC3, Tryptase, MCP-1 in ear tissue. These results demonstrated that BV has a suppressive effect on allergic reaction.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.14 no.2
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• pp.231-241
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• 2001

Mahwang-Shin-Gung-San has been found inhibiting the mast cell-mediated anaphylactic reaction. This report describes an inhibitory effect of Mahwang-Shin-Gung-San (MSGS) on the immediate-type cutaneous allergic reactions. MSGS has concentration -dependently inhibited the ear swelling response induced by compound 48/80 in mouse by intradermal injection. The mast cells in mouse ear tissue undergone ear-swelling response by compound 48/80 were stained by alcian blue/nuclear fast red. MSGS significantly inhibited the compound 48/80-induced degranulation from mast cells in ear tissue. MSGS concentration-dependently inhibited the histamine release from the rat peritoneal mast cells (RPMC) by compound 48/80. We also studied the effect of MSGS on mast cell-dependent passive cutaneous anaphylaxis (PCA) activated by dinitrophenyl IgE antibody. MSGS showed potent inhibition of PCA by oral administration. These results indicate that MSGS inhibits immediate-type allergic reactions by inhibition of mast cell degranulation in vivo and in vitro.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1012-1015
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• 2004

Digital hearing aids enclose $6{\sim}8$ tiny components. Those electromechanical components are individually wired by soldering which is a manual labor and sometimes causes components' damage by heating. This paper suggests a PCB design for overcome these problems. Several PCBs are designed and manufactured and circuited to produce ITE(In-the-Ear) type hearing aids which are inserted in the ear canal. The most optimal size of the PCB design for the ITE hearing aid is presented in this paper.

• Journal of radiological science and technology
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• v.39 no.2
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• pp.257-262
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• 2016

This study aimed to suggest a novel method of modeling a hearing aid ear shell based on Digital Imaging and Communication in Medicine (DICOM) in the hearing aid ear shell manufacturing method using a 3D printer. In the experiment, a 3D external auditory meatus was extracted by using the critical values in the DICOM volume images, and the modeling surface structures were compared in standard type STL (STereoLithography) files which could be recognized by a 3D printer. In this 3D modeling method, a conventional ear model was prepared, and the gaps between adjacent isograms produced by a 3D scanner were filled with 3D surface fragments to express the modeling structure. In this study, the same type of triangular surface structures were prepared by using the DICOM images. The result showed that the modeling surface structure based on the DICOM images provide the same environment that the conventional 3D printers may recognize, eventually enabling to print out the hearing aid ear shell shape.

• Biomolecules & Therapeutics
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• v.16 no.3
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• pp.237-242
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• 2008

The effect of Picrorrhiza Rhizoma (PR) aqueous extracts were evaluated on 2,4-dinitrofluorobenzene (DNFB)-induced contact dermatitis, type I allergic model. Contact dermatitis was induced by sensitization with dinitrophenyl-derivatized ovalbumin (DNP-OVA) and DNFB challenge as antigen. Three different concentrations of PR extracts (300,150 and 75mg/kg) were orally administered to DNP-OVA sensitization mice once a day for 7 days with reference materials; dexamethasone (15mg/kg, intraperitoneal treatment). End of 7 days oral administration of PR extracts or intraperitoneal treatment of dexamethasone, the changes on the edematous changes and scratching behavior were measured. Immediate after DNFB challenge on ear or paw of DNP-OVA sensitized mice, increases of ear and paw thicknesses and weights were detected with anterior ear skin (dermis to epidermis) thickness and paw scratching behavior increases. However, these DNFB-induced increases on ear and paw thicknesses, weights and scratching behaviors were decreased by treatment of all three different dosages of PR extracts and dexamethasone, respectively. In addition, the increases of anterior skin thicknesses were also dramatically inhibited by treatment of all three different dosages of PR extracts and dexamethasone at histopathological observations. The results obtained in this study suggest that oral treatment of PR extracts also has relatively favorable effects on allergic dermatitis.