• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.55-56
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• 2006

Directional antennas are used to improve spatial reuse, but have the problem of deafness. The DUDMAC protocol uses the ORTS, OCTS, DDATA, and DACK mechanisms and a blocking algorithm for directional transmissions. In this paper, we propose a tone dual-channel directional MAC (Tone DUDMAC) protocol to improve spatial reuse. The Tone DUDMAC protocol uses the ORTS, DCTS, DDATA, and DACK mechanisms including the DDATA_tone and OCTS_tone. We use ORTS as that in DUDMAC because of location unawareness of neighbor's nodes. The DDATA_tone and OCTS_tone reduce a blocking area and improve spatial reuse. We confirm the throughput performance of the proposed MAC protocol by computer simulations using Qualnet ver.3.8 simulator.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.113-114
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• 2007

무선 Ad Hoc 네트워크 환경에서 기존 IEEE 802.11 MAC 프로토콜에서 Omni-Directional 안테나를 이용하여 방식으로부터 자원의 활용을 늘이기 위해서 Directional 안테나를 이용한다. Directional 안테나의 사용으로 기존 802.11 MAC 프로토콜에 비해 Spatial reuse가 증가하고, 안테나의 높은 이득과 간섭의 감소, 그리고 전송범위의 증가의 장점을 갖는다. 그러나, Directional 안테나를 이용함으로서 New Hidden Problem, Deafness, 그리고 Capture 등과 같은 문제점이 발생하였다. 본 논문에서는 이러한 문제점들을 파악하고, 이를 해결하는 방안들을 분석하고 각 해결방안들에 대한 성능을 비교평가한다.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.17.1-17
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• 1983

Osteomas of the external auditory canal are considered clinically to be discrete, pedunculated bone lesions arising along the tympanosquamous suture. They are benign lesions but often are slowly progressive growth in size which eventually resulted in obstruction of the external auditory canal when this occurs the patient will complain of deafness. Exostoses, similar to the osteoma, are broad based elevations of bone usually multiple and bilaterally symmetric, involving the tympanic bone. Recently, the authors have experienced a case of osteoma of the external auditory canal, and so report with some reviews of the literatures.

• Journal of Korean Neurosurgical Society
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• v.38 no.3
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• pp.227-230
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• 2005

Hearing loss in the contralateral functioning ear is a rare and distressing complication after vetibular schwannoma removal. Various possible mechanisms have been proposed, however, the etiology of hearing loss is not clear. Fortunately, this is an extremely rare occurrence, sporadic case reports have appeared in the literatures. We report two cases of acute contralateral hearing loss after vestibular schwannoma removal and discuss the possible mechanisms of the phenomenon. Although permanent deafness may result, in our cases, the hearing loss was temporary, returning to near preoperative level within one month. The etiology of hearing loss in one case is thought to be cerebrospinal fluid leakage. However, in the other case, the cause of hearing loss is not clear. A better understanding of these events may lead to preventive measures to avoid contralateral hearing loss after vestibular schwannoma removal.

• Kidney Research and Clinical Practice
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• v.34 no.1
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• pp.53-56
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• 2015

MYH9-related disorder is an autosomal dominant disease caused by a mutation in the MYH9 gene, which encodes nonmuscle myosin heavy chain IIA (NMMHC-IIA). This disease is characterized by giant platelets, thrombocytopenia, granulocyte inclusion bodies, proteinuria, and high-pitch sensorineural deafness. Nephropathy has been observed in 30% of patients with MYH9-related disorder. The characteristic features are early onset proteinuria and rapidly progressing renal disorder. However, the prognosis of MYH9 nephropathy remains unclear. Herein, we describe a 36-year-old woman who presented with proteinuria and was diagnosed with MYH9 nephropathy via renal biopsy and gene analysis. Her proteinuria improved after administration of an angiotensin II receptor blocker, but was aggravated after changing to a calcium channel blocker.

• Journal of Medicine and Life Science
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• v.20 no.1
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• pp.43-47
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• 2023

Streptococcus suis (S. suis) is an emerging zoonotic pathogen that causes bacterial meningitis in humans. S. suis is an encapsulated gram-positive facultative anaerobic bacterium and is an important pathogen in pigs. This infectious disease usually manifests in humans as meningitis, endocarditis, septicemia, and arthritis. Most cases originate in Southeast Asia, and human S. suis infections are often reported in countries with a high density of pigs. Meningitis is a common clinical manifestation of S. suis infection. Moreover, hearing loss is a common complication that can be bilateral, profound, and/or permanent. This report presents two cases of bacterial meningitis and hearing loss caused by S. suis in patients without a history of direct exposure to pigs in an intensive pork industry region.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.90-90
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• 2003

Circling mice were recorded to display profound deafness and a head-tossing and bidirectional circling behavior, showing an autosomal recessive mode of inheritance. In addition, the histological examination of inner ears revealed that the region around organ of Corti, spiral ganglion neurons and outer hair cells showed definite abnormality. On the other hand, a genetic linkage map was constructed in an intraspecific backcross between cir and C57BL/6J mice. The cir gene was mapped to a region between D9Mitl16/D9Mit15 and D9Mit38 on the mouse chromosome 9. Estimated distances between cir and D9Mitl16, and between cir and D9Mit38 are 0.70 $\pm$ 0.40 and 0.23 $\pm$ 0.23 cM, respectively. The markers in order was defined as follows: centromere-D9Mit182- D9Mit51/ D9Mit79/ D9Mit310- D9Mit212/ D9Mit184- D9Mit116/ D9Mit15- cir- D9Mit38- D9Mit20- D9Mit243- D9Mit16- D9Mit55/ D9Mit125- D9Mit281 Based on genetic mapping, we constructed for a YAC contig across cir region. They covered the entire region or cir and cir gene was located on between the lactotransferrin (ltf) and the macrotubule-associated protein (map4). It is known that sr gene is localized in 64cM of mouse chromosome 9. The two mouse were found to be allelic by complementation test. Recently the spinner mouse has been mapped to our cir region, and tmie gene were elucidated. And further study will be needed in circling mouse to prove tmie gene mutaiton.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.29 no.2
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• pp.507-521
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• 1999

Osteopetrosis is an uncommon hereditary bone disorder whose prominent radiologic feature characterized by increased bone density. The authors reported a 7-year-old male patient who referred from local dental clinic for dental problems such as early exfoliation of deciduous teeth(#54,73,83) and delayed eruption of permanent teeth(#31.41.36.46). The patient appeared as a poorly developed. Dental X-ray films showed early exfoliation of deciduous teeth, delayed eruption of permanent teeth, and rampant caries. Lateral view of skull demonstrated increased opacity of calvarium, facial bones, and skull base. Generally the skeletal density is greatly increased throughout all bones. Facial CT showed poor development of paranasal sinuses and mastoid air cells. No hematopoietic and neurologic complications such as anemia, thrombocytopenia, blindness and deafness were found. Also mental retardation was not found. The final diagnosis of this case was a osteopetrosis tarda. Sometimes patient with osteopetrosis tarda may be developed dental problems prior to severe systemic symptoms. The dentist can be the first clinician to see the patient. It is very important for the dentist to have the knowledge of the osteopetrosis and to care the patient's dental problems to prevent complication such as osteomyelitis of jaws.

• Clinical and Experimental Reproductive Medicine
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• v.19 no.1
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• pp.95-101
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• 1992

During the years 1983 to 1991, cytogenetic analysis was performed on 19 women with Turner syndrome in order to find out the incidence of symptoms and signs according to the classification of chromosome abnormalities. 1. All of them showed short stature and the mean height in 7 adults was $140.71{\pm}5.26cm$. 2. Among the 19 patients with Turner syndrome, 7 (36.8%) had 45, XO karyotype, 7 (36.8%) had 46, Xi (Xq), and remained 5 (26.3%) had mosaicism. 3. Five patients with mosaicism had 45, X/46, XX (2), 45, X/46, Xi (Xq) (2) and 45, X/47, XXX (1), respectively. 4. Patients with 45, XO and 46, Xi (Xq) had amenorrhea, whereas only 33% (1/3) of patients with mosaicism had amenorrhea. Total incidence of amenorrhea was 84.6% (11/13). 5. Abnormal external genitalia was detected in 63.6% of patients. The incidence of abnormality in patients with mosaicism was lower than that of other groups. 6. OMPC and deafness were detected in 3 of 19 patients. 7. Two cases of cardiovascular abnormalities were found in patients with 45, XO. This study suggests that gnenetic counselling according to the classification of chromosomal abnormalities could be needed in patients with Turner syndrome.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.1079-1083
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• 2002

Dizziness is a common and often vexing symptom. But the cause of dizziness is very various and generally divided into peripheral and central. Although there are some clinical reports about dizziness. there isn't any report by Constitutional therapy. In this study, the author reports a case of recurrence and persistent vertigo. he was consulted to local E.N.T. and clinically suggested Menier's disease with tinnitus, mild deafness, and vertigo. By using the method of 8 Constitutional Acupuncture therapy and herbal medication(Mihudungsikjang-tang) regarding him as COLONOTONIA. After he regarded and treated as GOLONOTONIA, the symptoms disappeared.