장결핵의 임상적 고찰

정성수,박경남,이민호,기춘석,함준수,이종철,손주현,심종걸,윤호주 대한소화기내시경학회 1988 Clinical Endoscopy Vol.8 No.1

Intestinal tuberculosis is an infectious disease which is still prevalent in the developing countries including Korea. It may occur insidously, have a vague clinical marofestation, and take a chronic course. We have analyzed 101 cases of intestinal tuberculosis. proven by clinical and histopathologic diagnosis for 10yrs since 1977. The results are as follows: 1) Intestinal tbc was prevalent in the age of 20-30 and the male to female ratio was 1:1.7. 2) Among clinical manifestations, abdominal pain, and tenderness, general malaise and abdominal mass were observed in order of frequency. 3) Active pulmonary lesion was associated in 73 cases (73.3%). 4) Ileocecal region was the most frequent site of involvement in barium study and in colonoscopy. 5) The most frequent colonoscopic finding was multiple ulceration and pseudopolyposis and chronic granulomatous inflammation was noted in 58% on hitopathology. 6) Ulcerative type was the most common type 45.4% by intestinal x-ray and colonofiberscopic examination

의사입장에서 본 병원의 사회공헌활동

정성수,Jeong, Seong-Su 대한병원협회 2008 대한병원협회지 Vol.37 No.5

증강현실을 이용한 건물 모니터링 기법 개발

정성수,허준,우선규,Jeong, Seong-Su,Heo, Joon,Woo, Sun-Kyu 한국건설관리학회 2009 한국건설관리학회 논문집 Vol.10 No.6

In order to effectively distribute the resources, it is very critical to understand the status or progress of construction site quickly and accurately. Augmented Reality (AR) can provide this situation with information which is convenient and intuitive. Conventional implementation of AR in outdoor or construction site condition requires additional sensors or markers to track the position and direction of camera. This research is aimed to develop the technologies which can be utilized in gathering the information of constructing or constructed buildings and structures. The AR technique that does not require additional devices except for the camera was implemented to simplify the system and improve utility in inaccessible area. In order to do so, the position of camera's perspective center and direction of camera was estimated using exterior orientation techniques. And 3D drawing model of building was projected and overlapped using this information. The result shows that by using this technique, the virtual drawing image was registered on real image with few pixels of error. The technique and procedure introduced in this paper simplifies the hardware organization of AR system that makes it easier for the AR technology to be utilized with ease in construction site. Moreover, this technique will help the AR to be utilized even in inaccessible areas. In addition to this, it is expected that combining this technique and 4D CAD technology can provide the project manager with more intuitive and comprehensive information that simplifies the monitoring work of construction progress and planning.

경추부 골절환자의 후방인대군 손상

정성수,이종서,정호원,김지형 대한척추외과학회 2001 대한척추외과학회지 Vol.8 No.2

연구목적 : 자기 공명 영상을 이용하여 경추 골절 환자에서 경추 후방 인대 복합체 손상의 임상적, 방사선학적 특징을 정의하고자 하였다. 대상 및 방법 : 경추 손상으로 수술을 받은 40명의 환자에 대해 자기 공명 영상과 단순 방사선 촬영으로 손상 기전과 유형을 분류하였고 이 중 후방 또는 전ㆍ후방 수술을 이행했던 25명에 대해 자기 공명 영상 소견과 수술 소견을 비교 평가하여 상관 관계를 조사하였다. 결 과 : 후방 인대 복합체 손상은 전체 40명 환자 중 75%(30명)에서 발견되었으며, 신연ㆍ굴곡 손상 20명 중 90%(18명)에서, 압박ㆍ굴곡 손상 15명 중 73%(11명)에서 후방 인대 복합체 손상이 발견되었고, 수직ㆍ압박 손상 4명 중에서는 25%(1명) 만이 발견되었으며, 신연ㆍ신전 손상에서는 발견되지 않았다. 완전 척수 손상 환자 23명 중 96%(22명)에서 후방 인대복합체 손상이 관찰되었으며, 완전 척수 손상을 받지 않은 17명의 환자 중 (15명은 불완전 척수 손상, 2명은 척수 손상이 없었음) 47%(8명)에서 후방 인대 복합체 손상이 발견되었다. 후방 또는 전ㆍ후방 수술을 시행했던 25명에 대해 자기공명 영상 소견과 수술 소견을 비교 평가한 결과 수술 소견과 자기 공명 영상 촬영 소견은 높은 상관 관계를 보였다.(p<0.05). 결 론 : 경추 골절에서 후방 인대 복합체의 손상은 신연ㆍ굴곡 손상과 완전 척수 손상에서 가장 많이 동반되었으며, 손상 소견은 자기 공명 영상 촬영으로 잘 관찰할 수 있었다. 경추 골절 환자에서 후방 인대 복합체 손상시 자기 공명 영상은 수술 소견과 비교하여 민감도, 측이도, 정확도가 매우 높은 검사법으로 사료되며 치료 방법의 설정에도 도움이 될 것으로 생각된다. Objective : To define the clinical and radiological characteristics of the patients with injury of the posterior ligament complex of the cervical spine using MR imaging. Materials and Methods : Forty patients with acute cervical spine fracture who underwent surgery were examined with MR imaging and plain radiography. Twenty-five patients underwent posterior fusion. The MR findings were correlated with surgical findings, clinical findings. and plain radiographs. Results : Posterior ligament complex injury was detected in 75%(n=3O) of all patients. Of the 20 patients with distractive-flexion injury. 9O%(n=18) had posterior ligament complex injury (p<0.05). Of the 15 patients with compressive-flexion injury. 73% (n=11) had ligament injury. Of the 4 patients with vertical compression injury. 1 patient (25%) showed ligament injury. One patient with distractive-extension injury did not show ligament injury. Of the 23 patients with complete spinal cord injury. 96% (n=22) showed ligament tear (p<O.05). Of the 17 patients without complete cord injury (15 incomplete injury, 2 no cord injury), 47%(n=8) had ligament injury. Surgical findings were well correlated with MR imaging in patients who underwent posterior surgery (p<O.05). Conclusions : Injury of the posterior ligament complex in patients with cervical spine fracture was most common in patients with distractive-flexion injury and was more frequent with complete cord injury. MR imaging could reliably reveal such injuries.

속도센서를 이용한 흡음곁수 측정

정성수,김용태,조문재 한국물리학회 2005 새물리 Vol.51 No.1

The sound absorption coefficients of a polyester sample were measured by using a pressure microphone and a micro-flown that was developed by de Bree, and the results were compared. The experimental results show that both sensors could be well applied to measuring the sound absorption coefficient, but the microphone was much more stable than the micro-flown. In the case of the micro-flown, attention to the sound measurement direction relative to the incident wave was required.

교통수단의 저주파 소음 특성

정성수,김용태,서재갑,신수현 한국물리학회 2005 새물리 Vol.51 No.1

Low-frequency noise below 200 Hz, including infra-sound, is known to affect human circulatory,respiratory, nervous, and endocrine systems. Legislation has been introduced in several countries regarding evaluation guideline and measurement methods for low-frequency noise. In this research,low-frequency noise of road vehicles and trains are investigated. The measured results showed that the interior noise levels of the vehicles were much higher than the exterior noise levels. The peak noise frequencies in the interior of a bus and a train coincide well with the first resonance of the inner space. The interior noise level of road vehicles and trains in the frequency range of 8 100 Hz can give an oppressive feeling and a feeling of discomforts which is a cause for some concern.

방음벽 개발 동향 및 음향 특성

정성수 한국소음진동공학회 2002 소음 진동 Vol.12 No.6

방음벽 상단부 형상에 따른 삽입손실 연구

정성수,김용태,이우섭 한국음향학회 2002 한국음향학회지 Vol.21 No.7

The insertion loss of the noise barriers with several top shape is measured in an anechoic room by using a reduced scale model test. The insertion loss differences between a straight vertical barrier having 0.3 m height and several barriers with simple top shaped are compared. The results show that the latter is more effective than the former and absorptive barrier is more effective than the reflective one. Among the barrier types of 'T', 'Y', and '(equation omitted)', type 'Y' is the best one and the rest have similar effect. This result is well agree with Alfredson (PIOC. Inter-Noise 95, p. 381, 1995)'s but contradict to May (J. Sound Vb. 71, p. 73, 1980)'s. Therefore, it is difficult to determine which type is the best. In order to find out this discrepancy, boundary element method is adopted and the result shows one can have different result because each supposed different experimental conditions like height of noise barrier, positions of sound source and receiver, etc.

버스의 저주파 소음 분석

정성수,전병수,서재갑,김용태 한국물리학회 2009 새물리 Vol.59 No.5

Low-frequency noise below 250 Hz, including infrasound (< 20 Hz), is known to affect the human circulatory, respiratory, nervous, and endocrine systems. In the middle of the 1990's, some European countries prepared guidelines to measure and evaluate the low-frequency noise. We, however, are still in the initial stage of doing so. In this article, low-frequency noise levels of buses were investigated. The results indicated that the interior peak noise level was almost 100 dB at 12.5 and 16 Hz. The peak noise frequencies could be well explained by the first resonance of the inner space of the bus. The noise level of the bus in the frequency range between 12.5 and 50 Hz may lead to an oppressive and vibration feeling. Therefore, further research on the reduction of low-frequency noise is required for a quieter mass-transportation environment. 저주파 소음은 비록 귀에는 잘 들리지 않으나 장시간 노출될 경우 사람의 순환계, 호흡계, 신경계 그리고 내분비계 등에 영향을 주는 것으로 알려져 있다. 따라서 이미 몇몇 유럽국가들은 1990년 중반에 저주파 소음에 대한 측정 및 평가방법에 대한 지침서를 마련한 바 있으나 국내의 연구는 아직 초기단계에 있다. 본 연구에서는 대중교통 수단인 버스를 대상으로 버스 내 저주파 소음이 어느정도 발생되고 있는지를 살펴보았다. 측정결과 12.5와 16 Hz에서 100 dB 정도의 강한 피크 소음이 발생되었으며, 이것은 버스의 내부 공간에 대한 음향 공명 주파수에 해당됨을 알 수 있었다. 주파수 12.5 ~ 50 Hz 범위에서는 인체에 압박감과 진동감을 줄 수 있을 정도의 소음이 발생되므로 향후 저주파 소음 저감 대책에 대한 연구가 요구된다.

플라스틱 폼의 음향특성 조사

정성수,황철호 한국소음진동공학회 1996 소음 진동 Vol.6 No.3

The absorption coefficients of 3 largely reticulated urethan foams are measured by transfer function method which uses two microphones in an impedance tube. Based on the previously published data, the new modified empirical equations for predicting the characteristic impedance and propagation constant of the largely reticulated urethane foams are developed. Comparison is made between the measured data and the predicted data, based on the previously published equations and the new equation. Good agreement of the absorption coefficient between the measured and predicted data by the new modified empirical equation has been obtained.