• Journal of Biosystems Engineering
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• v.32 no.1 s.120
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• pp.57-62
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• 2007

The objectives of this study were to prepare a new artificial eardrum patch using water-insoluble chitosan for healing the tympanic membrane perforations and to investigate biomechanical properties and cyotoxicity of the chitosan patch scaffold (CPS). Tensile strength and elongation at the rupture point of CPSs were 2.49-74.05 MPa and 0.11-107.06%, respectively. As the biomechanical properties or CPSs varied with the concentration of chitosan and glycerol, the proper conditions for the CPS were found out. SEM analysis showed very smooth and uniform surface of CPSs without pores at x1000. The result of MTT test showed that CPSs had no cytotoxicity.

• Journal of Biomedical Engineering Research
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• v.32 no.4
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• pp.285-288
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• 2011

In this study, we developed an optical coherence tomography(OCT) using a sweep-source laser whose center wavelength is 1310 nm and a probe of hand-held type. The developed hand-held probe targets to diagnose the middle ear, so it is miniaturized for ease and convenience of control. For the first time, we performed in-vivo clinical experiments on tympanic membrane(TM) perforation patients not reported from previous studies about OCT. The high-resolution sectional images of tympanic membrane perforation can be obtained. There aren't many studies about diagnostic instrument of the middle ear and diagnosis with sectional image of the middle ear, so the developed OCT system and hand-held probe are applicable to tympanic membrane perforation and other pathologic diagnosis in the middle ear.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.471-480
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• 1995

The modification of Nl -N2 Audiograms before and after loudtone exposure onto the tympanic membrane of guinea pigs was examined. The exposure was a loud continuous tone of 106 dB SPL intensity at 10 KHz for 10 minutes. The comparison between Wl-H2 Audiograms pre and post loudtone exposure indicates that the exposed cochlea permanently lost its normal hearing function. The largest threshold shifts wore found between 12-13.2KHz. The functional change of the cochlea after the loudtone exposure depends on the state of the cochlea before the trauma. More sensitive cochlea is more critically damaged in its function after the trauma than less sensitive cochlea.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1979.05a
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• pp.3.1-3
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• 1979

The aim of ear operation is to cease otorrhea and to restore hearing. The ceasation of otorrhea and the graft of tympanic membrane are reached to successful stage, and yet hearing restoration process still remains further to need a matter of development. Authors carried out 67 cases hearing restoration operation among 154 patients who had been undertaken mastoid-tympanoplasty during period of Feb. 1978 through March 1979. 54 cases have been followed for this study among 67 cases hearing restoration operation. The used material of operation are almostly incus and some cases with TORP. This paper is dealing with its surgical method and postoperative audimetric study.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1377-1388
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• 2008

In our country where over 80% of land is mountainous, decomposed granite soils are often used as building materials for civil engineering works. Seashores are having great difficulties in management and treatment of marine byproducts that are left vulnerable. It is necessary to find a way to efficiently utilize such vulnerable marine byproducts. For this reason, shell and ocher were mixed together in order to efficiently utilize ocher that is being used frequently as a building material in civil works and shell that is a type of marine byproducts being thrown away. The purpose of this study is to examine the extent to which shell-ocher mixture can reduce liquefaction through cyclic triaxial test. The author of this study aims to provide the possibility for application at construction site of shell-ocher mixture.

• Journal of Yeungnam Medical Science
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• v.8 no.1
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• pp.127-135
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• 1991

Successful middle ear surgery requires the availability of al safe, effective bonding material. Side effect caused by synthetic materials have led to the use of biologic adhesive. However, they carry the risk of transmission of infectious diseases if they are prepared from pooled human blood. The adhesive strength of ammonium sulfate fibrin adhesive produce an adhesive strength that is half that of the homologous commercial product. It is, however, good enough for use in several otolaryngological operations, tympanoplasty, facial nerve repair, reconstruction of ossicles, reconstruction of posterior wall of ear canal and obliteration of frontal sinus and mastoid antrum using bone dust.

• Journal of Aquaculture
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• v.13 no.2
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• pp.175-179
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• 2000

Trochopore larvae of U. unicinctus were exposed to selected settlement stimuli. Within 5 - 10 min after addition of the UM, the settlement stimuli derived from the skin of adult echiuran, induced metamorphosis of trochopores to pelagosphera. However, the trochopores did not positively respond for settlement, when stimulated with normal sea water, sticky fluid drawn from Tegillarca granosa or blood of U. unicinctus. The thermo-sensitive UM was relatively stable at ambient temperature, but was destroyed at 70$^{\circ}$.

• The Journal of the Acoustical Society of Korea
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• v.31 no.5
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• pp.273-279
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• 2012

In this thesis, a nonlinear compression fitting method was studied for each frequency channel of a 64 channel digital hearing aid. Unlike conventional fitting formula method done from the result of the hearing loss test, the present fitting method uses the auditory threshold of sound pressure measured near the tympanic membrane while ITE (In-The-Ear) hearing aid is fitted into the user's ear canal. Also, the spectral distribution of the voice sound pressure was used for realizing of output sound pressure compression curves against input sound pressure level. Theoretical research results of FFT-iFFT compression algorithm has been evaluated by experimental gain measurements at each different input sound pressure level 50 dB, 70 dB, 90 dB respectively.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.25 no.3
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• pp.168-174
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• 2012

Objective : The purpose of this study is to report the effect of Oriental medicine on Chronic suppurative otitis media. Methods : We used herbal medication, acupuncture and cupping therapy were for treatment. To evaluate the results of the treatment, we observed the patient's condition and otoscopic findings. Results : The patient's objective and subjective symptoms showed noticeable improvement after treatment. Conclusions : We suggest that chronic suppurative otitis media can be treated by Oriental medicine effectively.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.37.2-38
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• 1981

Recently the efficacy of all ear drops in perforated tympanic membranes has been questioned and the safety of using the drugs intratympanically has been challanged. Many drugs not normally ototoxic when given systemically become ototoxic when administered via the middle ear. According to Stupp and others (1973) among neomycin, polymyxin-G, gentamycin, erythr omycin, tetracycline and penicillin, only penicillin was found to be free of toxic effects. The ototoxic antibiotics probably reach the inner ear by permeating the round window membrane, into the perilymph and then through Reissner's membrane to the endolymph. The main pathological changes are degeneration of stria vascularis, degeneration of sensory epithelia and degeneration of ganglion cells. We report with reference, a case of profound sensorineural deafness following the application of Terramycin powder intratympanically, in a 63 year old woman.