• Journal of IKEEE
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• v.14 no.1
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• pp.47-54
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• 2010

In this study, we analyzed the reduction of noise in a noise environment using 2, 3, 4 or 5 microphones in digital hearing aids. In order to be able to use this in actual digital hearing aids, we made the experiment microphone set similar to the behind-the-ear type (BTE) and then recorded the signal accordingly, with each situation. With the recorded signals, we reduced the noise in each signal by a noise reduction algorithm using multi-microphones. As a result, in the case of By comparing the SNR (Signal to Noise Ratio) and PESQ (Perceptual Evaluation of Speech) measurements, before and after the noise reduction, the results showed that the improvement in performance was highest when three or four microphones were used. Generally, when two or more microphones were used, we found that as the number of microphones increased there was an increase in performance.

• Journal of Sensor Science and Technology
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• v.13 no.1
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• pp.12-19
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• 2004

The tinnitus which is the one of the auditory disease is a phenomenon that the patients feel the sound in the ear or the head when there is no sound sources. There have been many therapies for this tinnitus so far, but it is known that the TRT (Tinnitus Retraining Therapy) is the most effective therapy. So we designed and developed the controllable white noise generator for TRT. It must be designed as small as possible for user's convenience, such as the ITE (In The Ear) type hearing aids. It used the thermal noise as the white noise source. And filter and tone control circuits are used at the end of the noise generation part to control the white noise characteristics. This link of the controllable circuits is used to change the white noise's characteristic for the various tinnitus patients' characteristic. we can confirm that the designed and implemented controllable white noise generator which is a ITE type operates properly by the experiments of filter and tone control circuit.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1976.06a
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• pp.87.1-87
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• 1976

Bekesy measured the sound transformation system of the middle ear 49 years ago. According to his reports, a ratio between the size of ear drum and the size of oval window is 17 : 1, and the lever function of the ossicles is physiologically 1.3 : 1. Therefore, the hearing might be aggravated to 27.5㏈ in the case of the vanishment of 3 ossicles. In 1952, Wullstein reported 5 types of tympanop-lasty and the fourth type among them was especially named for the sound-protection. The oval window is only exposed by the sound pressure and the round window is not exposed. According to the application by this idea, the post-operative hearing might be improved until 27.5㏈. Mean while, in 1942, Onchi verified through his experiment that the results of Bekesy's measurement was not completely conformed to Onchi result. Bekesy measured the sound pressure on the stapes plate of the oval window, on the other hand, Onchi measured the sound pressure on the surface of the perilymph of the oval window after removing the stapes plate(Fig. 1).(Figure omitted) The difference of their experiment is recognized that the impedance of the stapes plate exists or not (Fig. 1). Both Audiogrums are compared as Fig. 2. The result of IV type of tympanoplasty is success ful in 54% as the Table 1. (Table Omitted) The reason of unsatisfactory is caused by the thick and unmovable window-membrane and by the closing of air passage to the round window. The closing of the air passage to the round window is occurred by the adhesion between the grafting membrane and the surface of promontorium. In order to preserve this adhesion, I produce to transplantate the mucous membrane of the lip to the bone surface of tympanic cavity after removing the granulation tissue of the tympanic cavity and to form a membranous canal for the sake of air passage (Fig. 3). (Figure Omitted) The post-operative hearing by this method is shown as Fig. 4, 5. In other words, the post-operative sound pressure entered into the cochlea directly, by way of the oval window only, not by way of the round window, as a theorie of the sound protection. (Figure omitted)

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1470-1481
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• 2004

The purpose of this study was to research on facial shape to suggest a quantified data for the domestic apparel and beauty industry. Conducted a measurement research of 278 female college students, We took the photographs of front view and lateral view of the subjects by digital camera and obtained the 69 measurements through the facial measurement program. 264 ,subjects' measurement data were analyzed by various statistical methods such as descriptive analysis, factor analysis and cluster analysis. Using the 69 measurement items,4 factors were selected as key factors for the factor analysis of facial shape, the factors are: \circled1 Front face height \circled2 Side face radial length \circled3 Front face breadth \circled4 Ear height and Gnathion radial length. We categorized the facial shape into four types by cluster analysis. Type 4 is the most common facial shape in female college students: \circled1 Type 1: Round face \circled2 Type 2: Oval face \circled3 Type 3: Square face \circled4 Type 4: Heart shaped face According to the facial shape analysis, facial shape of female college students are consisting of Heart shaped face(34.8%), Round face(29.2%), Square face(23.5%), oval face(12.5%).

• Korean Journal of Plant Resources
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• v.25 no.2
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• pp.193-199
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• 2012

This study was carried out to evaluate the agronomic characteristics and biological activities of $Sorghum$ $bicolor$ germplasms introduced from USA. Plant height, stem diameter, tiller number, leaf length, leaf width, leaf vein color, ear type, ear length and ear width have different from the cultivated accessions. Sweet-N-Sterile (#4) showed the tallest height, widest ear-width and stem diameter. Most of $Sorghum$ $bicolor$ plants may be available to use for bio-energy from these results showing big biomass. Antioxidant activities of 11 cultivars collected from USA were examined by DPPH assay and reducing power. Among the cultivars, Premium stock (#1), Early Sumac (#7), SS Silage (#9) and WGF Grain Sorghum (#11) showed a significantly higher antioxidant activity in comparison to others. Early Sumac (#7) and SS silage (#9) showed more strong reducing power activities than ${\alpha}$-tocopherol, a positive control. Premium stock (#1), Sweet-N-Sterile (#4), Early Sumac (#7) and SS Silage (#9) were also showed high antioxidant activities by DPPH assay and reducing power experiment. BMR Gold I (#3) displayed strong antimicrobial activity against $Escherichia$ $coli$ at minimum inhibitory concentrations (125 ${\mu}g$/ml).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.4
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• pp.295-309
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• 2006

The present study was aimed to evaluate the incidence, etiological factors, and management of cleft lip and palate. Two hundred and twenty patients with cleft lip and/or cleft palate who were treated at Department of Oral and Maxillofacial Surgery, Chonnam National University Hospital, during the period between January 1994 and December 2003 were reviewed. The ratios of cleft lip : cleft lip with cleft palate : and cleft palate were 0.4:1.1:1. Males were more common than females in cleft lip (1.3:1) and cleft lip and palate (2.5:1), while females were more common than males in cleft palate (1:1.3). In the cleft side, left clefts were more prevalent than right clefts (cleft lip 1.3:1, cleft lip and palate 1.6:1). Unilateral clefts were more common than bilateral clefts in cleft lip (79:21). Cleft lip and cleft palate were more common in those with blood type A (34.5%) than those with other types. There was no significant relationship between birth season and frequency of clefts. The clefts were common in the first-born (48.8%), and in mothers aged between 25 and 29 (51.7%). Medication (24.7%) and stress (16.7%) during the first trimester were noted. Positive familial history was noted in 13 cases (5.9%). Thirty-two cases (15%) were associated with other congenital anomalies, in which tonguetie (40.6%) and congenital heart disease (21.9%) were most common. Among 100 patients with cleft palate, 77 patients had middle ear disease (77%), which occurred predominently in the incomplete cleft palate. Seventy-six among the 77 patients received myringotomy and ventilation tube insertion, and the remaining one received antibiotic medication only. Cleft lips were treated primarily at 3 to 6 months, and cleft palates were at 1 to 2 years. Treatment regimens included modified Millard method mainly in the cleft lip, and Wardill V-Y, Dorrance method, and Furlow method in the cleft palate. The percentage of palatal lengthening as type of cleft palate was greater in the incomplete cleft palate group (11.2%) than in the complete cleft palate group (9.6%). The percentage of palatal lengthening as operating method was no difference between the Furlow method (10.9%) and the push back method (10.7%). As postoperative complications, hypertrophic scar was most frequent in the cleft lip, and oronasal fistula in the cleft palate. In summary, it was shown that medication and stress during the first trimester of pregnancy were frequently associated with cleft lip and cleft palate, adequate timing and selection of method of operation are important factors to obtain morphologically and functionally good results. Furthermore prevention and treatment of middle ear disease are important in cleft palate patients because of its high co-occurrence.

• Korean Journal of Head & Neck Oncology
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• v.12 no.1
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• pp.81-87
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• 1996

We studied the clinical charcteristics of 265 cases of nasopharyngeal carcinomas diagnosed at Korea Cancer Center Hospital over a span of 8 years from Jan. 1987. Male were 187 and Female were 78 and male: female ratio was 2.4 : 1. The age distribution ranged from 2nd decade to 9th decade evenly and mean age was 46.1 years old. Histopathologically squamous cell carcinoma (WHO type 1, 2, 60.8%) were 161 cases and undifferentiated carcinoma (WHO type 3, 39.2%) were 104 cases. Main symptoms and signs were neck mass 199 cases (75.1%), ear symptoms 126(47.5%), nasal symptom 101 (38.1%). The distribution of anatomical subsites were posterior wall 75 (24.7%), lateral wall 175 (72.8%), Inferior wall 15 (2.5%). Tumor staging by AJCC classification, 1992, distributed with stage I 3 cases (1.1%), stage II 5 cases (1.9%), stage III 24 cases (9.1%), stage IV 233 cases (87.9%).

• The Journal of Internal Korean Medicine
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• v.19 no.2
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• pp.333-346
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• 1998

In order In study the effects of an immunosuppression and a mitigation of inflammation of Gamiseungmagalgeuntang(GMSG) on the allergic contact dermatitis, contact hypersensitivity assay, mast cell, VCAM-1, and T cell of the lymph node in mice induced allergic contact dermatitis by the contacts-sensitizing DNCB were obsereved after oral administration of GMSG extract. The results of this study were as follows ; 1. Ear swelling in contact hypersensitivity assay was decreased in the GMSG group as compared with DNCB group. 2. It was investigated that mast cells were appeared degranulated type in DNCB group and a number of granulated type was more GMSG group than DNCB group. 3. VCAM-1 expression in epidermis and CD11b positive cell in dermis were decreased In the GMSG group as compared with DNCB group. 4. In the lymph node ,the distribution of CD4, CD8, IL-2R positive cell were decreased at the cortex and medula in the GMSG group as compared with DNCB group.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.353-360
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• 1995

Gross and light microscopic findings are described for 34 canine sweat gland neoplasms including tumors derived from apocrine gland in anal sac and ceruminous gland in ear. Affected dogs are usually 5.2 years and sex predilection have not been seen. Sweat gland carcinoma(n=19) is predominant type for sweat gland neoplsm, while papillary syringadenoma(n=2) and spiradenoma(n=2) are rare type in this study. Distinct patterns identified in cutaneous sweat gland carcinoma are tubular(n=7), solid(n=5), mixed(n=4), papillary(n=2) and signet-ring(n=1). Mixed tumors which are characterized by myxomatous and chondroid metaplasia are seen in cutaneous sweat and ceruminous gland. The carcinoma derived apocrine gland of the anal sac induces humoral hypercalcemia of malignancy in two dogs in this study. Histologically, apocrine gland carcinoma of the anal sac has distinct rossette formation.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.2
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• pp.159-167
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• 1999

This paper presents a new transient voltage blocking device(TOBD)which low power and high frequency bandwidth to protect info-communication facilities from transient voltages. Conventional protection devices have some problems such as low frequency bandwidth low ener-gy capacity and high remnant voltage. in order to improve these limitations a hybrid type TOBD which consists of a gas tube avalanche diodes and junction type field effect transistor (JFETs) is developed. The TOBD differs from the conventional protection devices in configuration and JFETs are used as an active non-linear element and a high speed switching diode with low capacitance limited high current. Therefore the avalanche diode with low energy capacity are protected from the high current and the TOBD has a very small input capacitance. From the performance test using combination surge generator which can produce $1.2/50{\mu}m$ 4.2 kV/max, $8/20{\mu}m$ 2.1 kAmax it is confirmed that the proposed TOBD has an excellent protection per-formance in tight clamping voltage and limiting current characteristics.