http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
HVAC용 룸 유니트 (Room Unit)의 소음저감성능해석
김상렬,김현실,이성현,김봉기,김재승 대한조선학회 2012 대한조선학회 학술대회자료집 Vol.2012 No.5
In this paper, acoustic performance of the large-sized room units for ship HVAC system is studied. The room unit consists of a rectangular chamber of which inside partitions are covered by absorptive material with fabric skin. The room unit has one inlet and three outlets. At the inlet, a plane damper is installed to control the flow rate. The acoustic performance of a prototype room unit is measured using a HVAC mock-up. It is shown that insertion loss is comparable with that of a commercial room unit, although the prototype generates more flow noise than the commercial product. The major source of flow noise is analyzed by NADS-R, the noise analysis program for room unit. In order to reduce the flow noise, cone-shaped dampers are inserted into the room unit. It is shown that the cone-shaped damper decreases flow noise remarkably.
김상렬,김현실,김재승,김봉기,이성현,Kim, Sang-Ryul,kim, Hyun-Sil,Kim, Jae-Seung,Kim, Bong-Ki,Lee, Sung-Hyun 한국음향학회 2010 韓國音響學會誌 Vol.29 No.8
본 논문은 여객선용 HVAC 시스템 목업을 구축하여 HVAC 요소의 성능평가를 수행한 결과를 다루었다. 측정은 룸 유니트 (Room Unit), 소음기 등 6가지 종류에 대해 이루어졌으며 여러 유량에 대해 삽입손실을 측정하였다. 소음기 직경이 작고 유량이 클수록 유동소음이 커져서 소음저감효과를 방해하지만, 직경이 커질수록 유동소음의 효과는 작아지고 삽입손실은 최대 25 dB까지 나타남을 확인하였다. 디퓨저 형태의 룸 유니트는 대체로 삽입손실이 0 - 10 dB 이지만 노즐 형태는 삽입손실이 최대 -15 dB 까지 소음이 커질 수 있음을 확인하였다. 또한 덕트 배열에 따라 최대 2 dB 까지 실내소음이 차이날 수 있음을 보였으며 각 룸 유니트에 동일한 유량이 배출하도록 조절하는 것이 보다 낮은 소음레벨을 얻을 수 있음을 확인하였다. In this paper, evaluation of noise reduction performance of HVAC system for ships by means of HVAC mock-up system is presented. Test is done for six different types of HVAC elements including room unit, silencer, etc. It is found that when diameter of silencer is small and air flow is large, flow noise degrades insertion loss. However, as diameter of silencer becomes larger, the effect of flow noise becomes smaller, and insertion loss up to 25 dB is measured. It is observed that insertion loss of diffuser type room unit is usually between zero and 10 dB, whereas that of the nozzle type room unit can be down to - 15 dB. In addition, it is shown that changing duct arrangement can reduce cabin noise by up to 2 dB, and providing same air flow to each room unit is crucial for generating less noise.
김상렬,김수관,여환호 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.4
The purpose of this retrospective study is to investigate the effects of conscious sedation in an outpatient setting. Data from 292 patients (154 males, 138 females), sedated for minor oral surgery, were studied using various parameters including age and sex distribution, as well as according to procedures and each drug group. Results show that this intravenous conscious sedation technique is a safe and effective method of controlling behaviour, but one has to be prepared to deal with any emergencies or complications. The specific results are as follows : 1.Most procedures (265/292) were used to Valium mixed with Demerol and Midazolam mixed with Demerol. 2.Valium revealed a high incidence of pain upon injection and symptoms limited to daily activity and thrombophlebitis. 3.Nausea and vomiting manifested in the procedure using Demerol. 4.The patient manifested comfort similar in response to the same drugs used in another treatment.
김상렬,김두현,강동규 한국산업안전학회 2002 한국안전학회지 Vol.17 No.4
As the use of automatic handling equipment for sensitive semiconductor devices is rapidly increased, manufacturers of electronic components and equipments need to be more alert to the problem of electrostatic discharges(ESD). In order to analyze damage characteristics of semiconductor device damaged by ESD, this study adopts a new charged-device model(CDM), field-induced charged model(FCDM) simulator that is suitable for rapid, routine testing of semiconductor devices and provides a fast and inexpensive test that faithfully represents ESD hazards in plants. High voltage applied to the device under test is raised by the field of non-contacting electrodes in the FCDM simulator, which avoids premature device stressing and permits a faster test cycle. Discharge current and time are measured and calculated. The characteristics of electrostatic attenuation of domestic semiconductor devices are investigated to evaluate the ESD phenomena in the semiconductors. Also, the field charging mechanism, the device thresholds and failure modes are investigated and analyzed. The damaged devices obtained in the simulator are analyzed and evaluated by SEM. The results obtained in this paper can be used to prevent semiconductor devices from ESD hazards and be a foundation of research area and industry relevant to ESD phenomena.
김상렬,김도훈,최정배,엄재욱 대한이비인후과학회 2005 대한이비인후과학회지 두경부외과학 Vol.48 No.5
We present a case of osteoma that was diagnosed incidentally in the middle ear. Osteomas are benign tumors and may occur as a solitary lesion in the squama, mastoid, middle ear and petrous pyramid. Even though osteomas in the middle ear are extremely rare, those lesions may be one of the causes of the conductive hearing loss by impinging upon the ossicular chain. There are only 22 cases of osteoma reported in the medical literature to date. In most patients, the diagnosis is confirmed by CT scan or at the time of surgery. CT scanning of these disorders is very useful, especially in examining the extent of the lesion and detailed bone destruction.