• 제목/요약/키워드: Loss of head

검색결과 665건 처리시간 0.034초

Neoglottic Adjustment in Tracheoesophageal Phonation

  • Cho, Jung-Il;Kim, Young-Mo;Park, Won-Seok
    • 대한음성언어의학회:학술대회논문집
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    • 대한음성언어의학회 1999년도 제12회 학술대회
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    • pp.186-186
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    • 1999
  • Tracheoesophageal fistulation following total laryngectomy has widely been used for voice restoration, This technique make exhaled air to divert to hypopharynx where phayngoesophageal segment forms the neoglottis. Even through layngectomized patients loss the normal laryngeal adjustment for speaking, it has been known that voiced and voiceless sounds are prodused in TE phonation. Nine TE speakeres were subjected to present study designed to clarity the mechanism of neoglottic adjustment in TE phonation, Fiberoptic examination and radiologic studies were performed at all patients and EMG study was performed at 3 patients during I phonation. Fiberoptic & radiologic studies revealed the location of neoglottis, so called pharyngoesophargeal segment which was vibrated well. EMG activity increased for sound production at retropharyngeal prominence. These results indicated that neoglottic adjustment in TE phonation.

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직결식 변속펌프의 운전 방안에 대한 연구 (A Study on the Operating Characteristics of Variable Speed Pump for In-Line Booster Pumping Station)

  • 박종문;최성일;노형운;서상호;김상균
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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    • pp.191-196
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    • 2001
  • In the systems with largely pipe head loss, variable speed pumps are generally used because substantial energy saving can be expected from such systems by controlling pump speed and also they offer simpler maintenance and operational ease even in conditions where abrupt changes In flow rate and head can occur. The invertor or the fluid coupling system are mainly adopted to control the rotating speed. In this paper, operating conditions at Migum pressing pump station(5 stage), where the fluid coupling system was the first installed for KOWACO, are investigated and analysed so that information thus gained can be usefully employed in the efficient operation of variable speed pump in new installations of in-line booster pumping station.

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신생아 청력장애의 선별검사와 의의 (Newborn heating screening)

  • 김리석
    • Clinical and Experimental Pediatrics
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    • 제50권1호
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    • pp.7-13
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    • 2007
  • Hearing loss in newborns is the most frequently occurring birth defect. If hearing impaired children are not identified and managed early, it is difficult for many of them to acquire the fundamental language, social and cognitive skills that provide the foundation for later schooling and success in society. All newborns, both high and low risk, should be screened for hearing loss in the birth hospital prior discharge (Universal Newborn Heaing Screening, UNHS). Objective physiologic measures must be used to detect newborns and very young infants with hearing loss. Recent technological developments have produced screening methods and both evoked otoacoustic emission (EOAE) and auditory brainstem response (ABR) have been successfully implemented for UNHS. Audiologic evaluation should be carried out before 3 months of age and infants with confirmed hearing loss should receive intervention before 6 months of age. All infants who pass newborn hearing screening but who have risk indicators for other auditory disorders and/or speech and language delay receive ongoing audiologic surveillance and monitoring for communication development. Infants with sensorineural hearing loss are managed with hearing aids and receive auditory and speech-language rehabilitation therapies. Cochlear implants can be an outstanding option for certain children aged 12 months and older with severe to profound hearing loss who show limited benefit from conventional amplifications.

Sorghum Harvesting Using a Head-feeding Type Rice Combine

  • Jun, Hyeon Jong;Choi, Il Su;Kang, Tae Gyoung;Choi, Yong;Choi, Duck Kyu;Lee, Choung Keun;Kim, Sang Hun
    • Journal of Biosystems Engineering
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    • 제43권4호
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    • pp.296-302
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    • 2018
  • Purpose: The aim of this study was to determine appropriate threshing and selection conditions for sorghum harvesting using a rice combine-harvester. Methods: Sorghum harvesting performance was tested using an actual rice combine. Through this test, the grain loss rate and the composition of crops according to the engine and fan speeds of the combine were investigated. Furthermore, the optimal threshing and selection conditions were determined by carrying out a harvest test based on the opening size factor of the concave in a test field. Results: The grain loss rate for the sorghum using a concave ($18{\times}18mm$) of the rice combine was the lowest at 0.1% at a chaffer angle of $40^{\circ}$, engine speed of 2000 rpm, and fan speed of 20 m/s, but the sorting sieve clogged frequently. Furthermore, as the engine speed and fan speed increased, the grain loss rate also increased. The sorghum harvesting test results of the combine according to the concave opening size showed that the grain loss rate was 0.5% at a driving speed of 0.5 m/s, with a concave opening diameter of 13 mm, a chaffer angle of $40^{\circ}$, a concave sieve oscillation frequency of 4.8 Hz, a fan speed of 20 m/s, and an engine speed of 2000 rpm. Conclusions: Findings showed that sorghum could be harvested using a head feeding rice combine.

Influence of Guide Vane Setting in Pump Mode on Performance Characteristics of a Pump-Turbine

  • Li, Deyou;Wang, Hongjie;Nielsen, Torbjorn K.;Gong, Ruzhi;Wei, Xianzhu;Qin, Daqing
    • International Journal of Fluid Machinery and Systems
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    • 제10권2호
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    • pp.154-163
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    • 2017
  • Performance characteristics in pump mode of pump-turbines are vital for the safe and effective operation of pumped storage power plants. However, the head characteristics are different under different guide vane openings. In this paper, 3-D steady simulations were performed under 13mm, 19mm and 25mm guide vane openings. Three groups of operating points under the three GVOs were chosen based on experimental validation to investigate the influence of guide vane setting on flow patterns upstream and downstream. The results reveal that, the guide vane setting will obviously change the flow pattern downstream, which in turn influences the flow upstream. It shows a strong effect on hydraulic loss (power dissipation) in the guide and stay vanes. It is also found that the hydraulic loss mainly comes from the flow separation and vortices. In addition, in some operating conditions, the change of guide vane opening will change the flow angle at the runner inlet and outlet, which will change the Euler momentum (power input). The joint action of Euler momentum and hydraulic loss results in the change of the head characteristics.

Anatomical and Pathological Findings of Magnetic Resonance Imaging in Idiopathic Sudden Sensorineural Hearing Loss

  • Kim, Min Bum;Lim, Jihyun;Moon, Il Joon
    • Journal of Audiology & Otology
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    • 제24권4호
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    • pp.198-203
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    • 2020
  • Background and Objectives: We sought to evaluate the diagnostic and prognostic value of measurable parameters of internal auditory canal (IAC) magnetic resonance imaging (MRI) in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). Subjects and Methods: We retrospectively reviewed the patients with ISSNHL who underwent IAC MRI from January 2008 to March 2019. Measurable parameters of IAC MRI, such as the diameter of the IAC, bony cochlear nerve canal, and cross-sectional area of the cochlear nerve, were measured by a single examiner. These parameters were then compared between the affected and healthy sides. Inner-ear abnormalities such as intralabyrinthine hemorrhage or labyrinthitis were also evaluated. The relationship between the surveyed parameters and the diagnosis of ISSNHL was assessed. Results: A total of 208 patients with ISSNHL were included. The measured parameters of IAC MRI were not different between the affected and healthy sides and were also not associated with the diagnosis of ISSNHL. However, inner-ear abnormalities of IAC MRI in ISSNHL displayed a significant association with worse hearing before and after treatment. An age that was older than 40 years also correlated with poorer outcomes. Further, inner-ear abnormalities were more frequently detected when IAC MRI was performed early after ISSNHL onset. Conclusions: Patients with ISSNHL and inner ear abnormalities such as intralabyrinthine hemorrhage or labyrinthitis identified via IAC MRI may experience poorer hearing outcomes. To detect such abnormal findings, it is recommended to perform IAC MRI early after the onset of ISSNHL.

Anatomical and Pathological Findings of Magnetic Resonance Imaging in Idiopathic Sudden Sensorineural Hearing Loss

  • Kim, Min Bum;Lim, Jihyun;Moon, Il Joon
    • 대한청각학회지
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    • 제24권4호
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    • pp.198-203
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    • 2020
  • Background and Objectives: We sought to evaluate the diagnostic and prognostic value of measurable parameters of internal auditory canal (IAC) magnetic resonance imaging (MRI) in patients with idiopathic sudden sensorineural hearing loss (ISSNHL). Subjects and Methods: We retrospectively reviewed the patients with ISSNHL who underwent IAC MRI from January 2008 to March 2019. Measurable parameters of IAC MRI, such as the diameter of the IAC, bony cochlear nerve canal, and cross-sectional area of the cochlear nerve, were measured by a single examiner. These parameters were then compared between the affected and healthy sides. Inner-ear abnormalities such as intralabyrinthine hemorrhage or labyrinthitis were also evaluated. The relationship between the surveyed parameters and the diagnosis of ISSNHL was assessed. Results: A total of 208 patients with ISSNHL were included. The measured parameters of IAC MRI were not different between the affected and healthy sides and were also not associated with the diagnosis of ISSNHL. However, inner-ear abnormalities of IAC MRI in ISSNHL displayed a significant association with worse hearing before and after treatment. An age that was older than 40 years also correlated with poorer outcomes. Further, inner-ear abnormalities were more frequently detected when IAC MRI was performed early after ISSNHL onset. Conclusions: Patients with ISSNHL and inner ear abnormalities such as intralabyrinthine hemorrhage or labyrinthitis identified via IAC MRI may experience poorer hearing outcomes. To detect such abnormal findings, it is recommended to perform IAC MRI early after the onset of ISSNHL.

아가미귀 증후군 1예 (A Case of Branchio-Otic Syndrome)

  • 홍정주;신유섭;김윤태;김철호
    • 대한두경부종양학회지
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    • 제27권1호
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    • pp.84-87
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    • 2011
  • Branchio-otic syndrome(BOS) is a relatively uncommon genetic malformation associated with dysmorphogenesis of the first and second branchial arches and is characterized by branchial fistulae, congenital preauricular fistulae, and anomalies of the pinnae, external, middle, and inner ears, accompanied by hearing loss. Recently, we experienced a case of BOS in a 10 years old female patient and report this case with a review of literature. 10-year-old girl presented with hearing impairment, bilateral preauricular fistula and cervical fistula. The pure tone audiometry revealed that she had 60dB sensorineural hearing loss on right side and 90dB mixed hearing loss on left. Bilateral branchial fistula was found on the neck CT scan and bilateral ossicular and cochlear abnormality combined with enlarged internal auditory canal was noted on the temporal bone CT scan. To investigate the association with EYA1 gene, we performed DNA sequncing with peripheral white blood cell and found the point mutations on Exon 7, 12 and 16 of EYA1 gene. The preauricular fistula and branchial fistula was excised surgically and hearing aid was applied on her left side. There was no sign of fistula recurrence for seven years after the surgery.

자탈형(自脱型) 콤바인의 배진손실(排塵損失)에 관(關)한 연구(硏究)(II) -품종(品種), 배진조절판(排塵調節板)의 위치, 작업속도(作業速度)가 배진손실량(排塵損失量)에 미치는 영향- (Chaff-outlet Grain Loss of Head-feed Combine -Changes in chaff-outlet gram loss on the variety, location of chaff-outlet loss control plate and traveling speed-)

  • 정창주;최중섭;최영수;정수일
    • Journal of Biosystems Engineering
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    • 제15권4호
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    • pp.310-318
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    • 1990
  • The amount of grain loss incurred during harvesting operation through the chaff-outlet of combine may not be negligible. To minimize this grain loss and optimize condition of combining, it may be necessary that the amout of chaff-outlet loss dependent on varying crop condition is to be estimated as exactly as possible. This study was thus intended to develop the monitor that could indicate the amount of grain lost through the chaff-outlet of combine during haravesting operation, and to find out driving and operating method of combine that could reduce chaff-outlet loss. In the study(1), the frequency distributions of each sound generated by the impact of kernels and chaff, the sound generated by the impact of the mixture of kernels and chaff, and vibration or noise created by the combine engine and other moving parts were investigated experimentally. Based on the results of frequency analyses, the loss monitor was developed which could measure the impact sound of paddy kernels that could be distinguished from those of other threshing products through chaff-outlet, and from vibration or noise created by the combine engine and other moving parts. Also in this study, detecting capability of monitor was tested by comparing the amount of grain lost through chaff-outlet with the amount of grain detected by the loss monitor, and changes in chaff-outlet grain loss on the increase of traveling speed, location of chaff-outlet loss control plate and variety of paddy rice were measured using the loss monitor. The monitor developed in this study efficiently measured the amount of grain lost through the chaff-outlet of combine. It was found that the chaff-outlet grain loss ratio was affected greatly by the variety of paddy rice, the location of chaff-outlet loss control plate and traveling speed of combine.

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갑상선 유두상 암종을 동반한 거대 경동맥체 종양 1예 (A Case of Huge Carotid Body Tumor with Thyroid Papillary Carcinoma)

  • 전진형;박일석;이원종;김성동;오석준;윤대영;노영수
    • 대한두경부종양학회지
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    • 제17권2호
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    • pp.221-225
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    • 2001
  • Carotid body tumor is a rare benign tumor arising from the paraganglionic tissue of neural crest. Surgical management remains the prefered treatment. Large carotid body tumors frequently encircle the internal carotid and external carotid arteries, and extensive bleeding often complicates the resection, increasing the risk of carotid artery rupture and damage to major cranial nerves. Recent improvements in surgical techniques and selective embolization have lessened the risks of surgical excision, decreased blood loss, and diminished the time required for resection. The review of literatures revealed a few cases of the carotid body tumor with papillary carcinoma of the thyroid. We report a case of the huge carotid body tumor with papillary carcinoma of the thyroid, which was removed by 4 times of preoperative embolization and transcervical approach.

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