한국인 폐확산능 정상예측식의 임상적 유용성과 정확성

나승원 ( Seung Won Ra ),박태선 ( Tai Sun Park ),홍윤기 ( Yoon Ki Hong ),홍상범 ( Sang Bum Hong ),심태선 ( Tae Sun Shim ),임채만 ( Chae Man Lim ),이상도 ( Sang Do Lee ),고윤석 ( Youn Suck Koh ),김우성 ( Woo Sung Kim ),김동순 ( Dong 대한결핵 및 호흡기학회 2008 Tuberculosis and Respiratory Diseases Vol.64 No.2

연구배경: 폐확산능을 해석하는 데 필요한 정상예측식으로는 한국인을 대상으로 하여 박 등이 개발한 식(박 식)이 있으나 아직 외국 정상예측식을 많이 사용하고 있다. 이에 국내에서 많이 사용하는 외국 정상예측식인 Burrows 식과 박 식의 임상적 유용성과 정확성을 비교하고자 하였다. 방법: 1. 임상적 유용성 연구; 2006년 7월부터 12월까지 6개월간 폐확산능검사를 시행한 환자 중 두 식을 각각 정상예측식으로 적용하였을 때 폐확산능 해석이 다른 276명(대상군 A)을 대상으로 하였다. 대상군 A에게 두 식을 각각 적용하였을 때 폐확산능 해석과 임상적 판단과의 일치도를 비교하여 임상적 유용성을 평가하였다. 2. 간질성폐질환 진단의 정확성 비교; 2001년부터 2006년까지 폐조직검사를 시행하여 확진된 간질성폐질환군과 서울아산병원에서 모집한 정상군을 대상으로 하여 정상예측식으로 두 식을 각각 적용하였을 때 폐확산능 해석의 정확도를 비교하였고, 두 식이 차이가 나는지 맥니머의 카이스퀘어 검정을 하였다. 결과: 1. 임상적 판단과의 일치도 비교; 276명을 임상정보를 토대로 폐확산능을 예측하여 분류한 결과 정상 54명, 감소 220명, 불분명이 2명이었다. 예측식으로 박 식과 Burrows 식을 적용하였을 때 임상적 판단과 일치하는 환자는 각각 78%와 22%이었다(p<0.001). 2. 간질성폐질환 진단의 정확성 비교; 박 식은 민감도 90.1%, 특이도 100%이었고 Burrows 식은 민감도 64.2%, 특이도 100%로 민감도가 통계학적으로 유의하게 박 식이 높았다(p<0.001). 결론: 우리나라 정상예측식인 박 식이 외국 정상예측식인 Burrows 식을 정상예측식으로 적용하는 것보다 임상적 유용성이나 간질성폐질환 진단의 민감도에서 더 우월하였다. 향후 폐확산능검사의 정상예측식으로 박 식을 사용해야 할 것으로 사료된다. Background: Park et al. developed the Korean reference equation for the measurement of diffusing capacity in 1985. However, the equation has not been widely used in Korea and foreign reference equations have been popularly used. We intended to compare the clinical usefulness and the accuracy of the the Korean reference equation (Park`s equation) with that of the foreign equation (Burrows` equation) that is commonly used in Korea. Methods: 1. Evaluation of clinical usefulness; Among 1,584 patients who underwent diffusing capacity (DLCO) at the Asan Medical Center from July to December 2006, group A subjects included 276 patients who had different interpretations of DLCO in trials employing Burrows` equation and Park`s equation. Clinical assessment was decided by consensus of two respiratory physicians. In order to evaluate the clinical usefulness of Burrows` equation and Park`s equation, agreement of clinical assessment and DLCO interpretation were measured. 2. Evaluation of accuracy; Group B subjects were 81 patients with interstitial lung disease (ILD) and 39 normal subjects. The 81 ILD patients were diagnosed following a surgical lung biopsy. The accuracy of diagnosing ILD as well as sensitivity and specificity were evaluated according to the use of the reference equations (Burrows` equation and Park`s equation) for DLCO. Results: Agreement between clinical assessment and interpretation of DLCO was 22% for the use of Burrows` equation and 78% for the use of Park`s equation. The sensitivity and specificity of the Burrows` equation for diagnosing ILD were 64.2% and 100%. The sensitivity and specificity of the Park`s equation for diagnosing ILD were 90.1% and 100%. The sensitivity of the Park`s equation for diagnosing ILD was significantly higher than that of Burrows` equation (p<0.001). Conclusion: The Korean reference equation (Park`s equation) was more clinically useful and had higher sensitivity for diagnosing ILD than the foreign reference equation (Burrows` equation). (Tuberc Respir Dis 2008;64:80-86)

도심에 거주하는 남성 노인에 있어서 유산소 운동능력이 혈관내 염증수치와 동맥경직도에 미치는 영향

안기만(Ki man Ahn),김윤신(Yoon shin Kim),박원하(Won Hah Park) 한양대학교 고령사회연구원 2012 한양고령사회논집 Vol.3 No.1

Experimental epidemiology and clinical studies have provided strong evidence that physical exercise has beneficial effects on multiple physiological variables affecting cardiovascular health. Cardiopulmonary function has been previously associated with atherosclerotic disease and coronary events. The aim of this study was to examine the higher levels of cardiopulmonary function are associated with lower levels of hs-CRP(high sensitive C reactive protein) and baPWV(barcahial ankle pulse wave velocity) in Korean elderly men. Study participants were 115 elderly men (mean age 62.5±2.2) participated in the research. Age, body mass index(BMI), resting heart rate, blood pressure, medical history, lipid profile, high sensitivity C-reactive protein(hs-CRP), Brachial-ankle pulse wave velocity (ba-PWV), cardiopulmonary function were measured. VO2peak higher elderly man had a significantly decreased hsCRP(0.22±0.26, p<0.05) and PWV (1439.1±159.9, p<0.05). In addition, HDL-C(55.2±14.2, p<0.05) levels was significantly increased and LDL-C(1193±21.7, p<0.05) level was decreased. This study show that VO2peak levels are positively correlated with hsCRP, HDL-C and PWV. Apparently healthy subjects with increased inflammatory markers have increased systemic arterial stiffness, which might reflect early atherosclerotic changes. Higher physical conditioning status, indexed by VO2peak, was associated with reduced arterial stiffness and hsCRP and increased HDL-C. The results of our study suggest that high cardiopulmonary function reduces hsCRP levels and improves PWV, HDL-C in Korea elderly men. 심혈관질환은 현재 선진 산업 국가들에서 성인 사망 제 1원인으로 알려져 있다. 심혈관질환에 의한 사망률은 나이가 증가하면서 더 높아지는 것으로 보고되고 있다. 이러한 심혈관질환을 일으키는 위험인자로는 나이, 신체활동의 부족, C반응성 단백(CRP), 혈관경직도(baPWV) 등이 심혈관질환을 높이는 것으로 보고되고 있다. 무엇보다 인구의 고령화로 인해 심혈관질환이 증가하고 있다는 것이다. 심혈관질환을 예방하기 위해서는 생활 습관 개선이 중요하며 그 중에서도 신체활동은 매우 중요하다. 하지만 고령의 건강한 남성을 대상으로 심폐기능과 관상동맥질환의 위험인자와의 관련성을 살펴본 연구는 부족하다. 따라서 본 연구는 60세 이상의 건강한 노인 남성(62.5±2.2)을 대상으로 심폐체력의 수준에 따른 혈중 C반응성 단백(CRP), 혈관경직도(baPWV)의 변화를 알아보고자 했다. 심장병 증상이 없는 노인 남성 115명을 대상으로 하였으며, 심폐기능 측정을 위해 운동부하검사를 실시했다. 혈액검사를 통해 혈중 CRP와 동맥경직도를 평가하기위해 baPWV 검사를 실시하였다. 그 결과 혈중 CRP는 심폐기능이 높은 그룹에서 0.22±0.26로 심폐기능이 낮은 그룹의 0.49±0.49 보다 유의하게 낮은 것으로 나타났다(p<0.05). baPWV역시 심폐기능이 높은 그룹에서 1439.1±159.9로 심폐기능이 낮은 그룹의 1523.7±236.1보다 낮게 나타났다(p<0.05). 따라서 건강한 노인 남성의 경우 심페기능이 좋은 그룹에서 심혈관질환 위험인자인 CRP와 baPWV가 유의하게 낮은 것으로 나타났다.

Influence of Bundle Diameter and Attachment Point on Kinematic Behavior in Double Bundle Anterior Cruciate Ligament Reconstruction Using Computational Model

Kwon, Oh Soo,Purevsuren, Tserenchimed,Kim, Kyungsoo,Park, Won Man,Kwon, Tae-Kyu,Kim, Yoon Hyuk Hindawi Publishing Corporation 2014 Computational and mathematical methods in medicine Vol.2014 No.-

<P>A protocol to choose the graft diameter attachment point of each bundle has not yet been determined since they are usually dependent on a surgeon's preference. Therefore, the influence of bundle diameters and attachment points on the kinematics of the knee joint needs to be quantitatively analyzed. A three-dimensional knee model was reconstructed with computed tomography images of a 26-year-old man. Based on the model, models of double bundle anterior cruciate ligament (ACL) reconstruction were developed. The anterior tibial translations for the anterior drawer test and the internal tibial rotation for the pivot shift test were investigated according to variation of bundle diameters and attachment points. For the model in this study, the knee kinematics after the double bundle ACL reconstruction were dependent on the attachment point and not much influenced by the bundle diameter although larger sized anterior-medial bundles provided increased stability in the knee joint. Therefore, in the clinical setting, the bundle attachment point needs to be considered prior to the bundle diameter, and the current selection method of graft diameters for both bundles appears justified.</P>

Debris transport evaluation during the blow-down phase of a LOCA using computational fluid dynamics

Park, Jong Pil,Jeong, Ji Hwan,Kim, Won Tae,Kim, Man Woong,Park, Ju Yeop Elsevier 2011 Nuclear engineering and design Vol.241 No.8

<P><B>Highlights</B></P><P>► We conducted CFD simulation on the spreading of the coolant in the containment after a break of the hot leg. It is used to estimate the dispersion of the debris within the containment. ► It was assumed that the small and fine debris is transported by the discharge flow so that a fraction of the small and fine debris transport can be estimated based on the amount of water. ► The break flow was assumed to be a homogeneous two-phase mixture without phase separation. Isenthalpic expansion of the break flow was used to specify the inlet boundary condition of the break flow. ► The fraction of the small and fine debris transported to the upper part is 73%; this value is close to the value calculated using 1D lumped-parameter codes by the USNRC and the KINS, respectively, while 48% more than the value shown in the NEI 04-07.</P> <P><B>Abstract</B></P><P>The performance of the emergency recirculation water sump under the influence of debris accumulation following a loss-of-coolant accident (LOCA) has long been of safety concern. Debris generation and transport during a LOCA are significantly influenced by the characteristics of the ejected coolant flow. One-dimensional analyses previously have been attempted to evaluate the debris transport during the blow-down phase but the transport evaluation still has large uncertainties. In this work, a computational fluid dynamics (CFD) analysis was utilized to evaluate small and fine debris transport during the blow-down phase of a pressurized water reactor, OPR1000. The coolant ejected from the ruptured hot-leg was assumed to expand in an isenthalpic process. The transport of small and fine debris was assumed to be dominated by water-borne transport, and the transport fractions for the upper and lower parts of the containment were quantified based on the CFD analysis. It was estimated that 73% of small and fine debris is transported to the upper part of the containment. This value is close to the values estimated by nuclear regulatory bodies of The United States and Korea using one-dimensional models while it shows a large discrepancy from the value suggested in the NEI 04-07 baseline analysis.</P>

A Study on Real-Time Autonomous Travelling Control of Two-wheel Driving Robot Based Ultrasonic Sensors

Won-Jun hwang(황원준),In-Man Park(박인만),Un-Wook Kang(강언욱),Sung-Hyun Han(한성현) 한국산업융합학회 2014 한국산업융합학회 논문집 Vol.17 No.3

We propose a new technique for autonomous navigation and travelling of mobile robot based on ultrasonic sensors through the narrow labyrinth that leave only distance of a few centimeters on each side between the guides and the robot. In our current implementation the ultrasonic sensor system fires at a rate of 100 ms, that is, each of the 8 sensors fires once during each 100 ms interval. This is a very good firing rate, implemented here for optimal performance. This paper presents an extensively tested and verified solution to the problem of obstacle avoidance. Our solution is based on the optimal placement of ultrasonic sensors at strategic locations around the robot. Both the sensor location and the associated navigation algorithm are defined in such a way that only the accurate radial sonar data is used for accurate travelling.

제1형 다발성 내분비 종양 1예

이도상(Do Sang Lee),송무형(Moo Hyung Song),김욱(Wook KIm),박일영(Il Young Park),원종만(Jong Man Won) 대한외과학회 1997 Annals of Surgical Treatment and Research Vol.53 No.2

High-strength bulk Al-based bimodal ultrafine eutectic composite with enhanced plasticity

Park, Jin Man,Mattern, Norbert,Kü,hn, Uta,Eckert, Jü,rgen,Kim, Ki Buem,Kim, Won Tae,Chattopadhyay, Kamanio,Kim, Do Hyang Cambridge University Press (Materials Research Soc 2009 Journal of materials research Vol.24 No.8

<P>An in situ bulk ultrafine bimodal eutectic Al-Cu-Si composite was synthesized by solidification. This heterostructured composite with microstructural length scale hierarchy in the eutectic microstructure, which combines an ultrafine-scale binary cellular eutectic (α-Al + Al2Cu) and a nanometer-sized anomalous ternary eutectic (α-Al + Al2Cu + Si), exhibits high fracture strength (1.1 ± 0.1 GPa) and large compressive plastic strain (11 ± 2%) at room temperature. The improved compressive plasticity of the bimodal-nanoeutectic composite originates from homogeneous and uniform distribution of inhomogeneous plastic deformation (localized shear bands), together with strong interaction between shear bands in the spatially heterogeneous structure.</P>

Efficacy of a commercial live attenuated <i>Lawsonia intracellularis</i> vaccine in a large scale field trial in Korea

Park, Sangshin,Lee, Joong-Bok,Kim, Kyung-Jin,Oh, Yu-Sik,Kim, Man-Ok,Oh, Yu-Ri,Hwang, Min-A,Lee, Jung-Ah,Lee, Sang-Won The Korean Vaccine Society 2013 Clinical and Experimental Vaccine Research Vol.2 No.2

<P><B>Purpose</B></P><P>Porcine proliferative enteropathy (PPE) is known as one of the most important risk factors causing economic losses in swine industry worldwide. This study was conducted to evaluate the efficacy of a commercial oral attenuated <I>Lawsonia intracellularis</I> vaccine (Enterisol Ileitis) against PPE under a commercial pig farm condition in Korea.</P><P><B>Materials and Methods</B></P><P>Thirty two-day-old 672 piglets were randomly allocated into vaccinated and control groups. All piglets in the vaccinated group were inoculated with a commercial attenuated <I>L. intracellularis</I> vaccine as following the manufacturer's instruction. Body weights of all pigs in both groups were measured on the vaccination day and 6, 14, and 20 weeks post vaccination and an average daily weight gain (ADWG) was calculated. Health status was observed biweekly during the whole trial.</P><P><B>Results</B></P><P>The vaccinated group showed significantly higher body weight (p<0.05) and ADWG (p<0.05) than those of the control group. The vaccinated group had significantly reduced impairments in activity, growth, defecation frequency, and stool hardness (p<0.05). Additional health benefits and improved weight gain by the vaccination produced a 4.2:1 return of investment, and the higher gross margin was $4.80 per pig.</P><P><B>Conclusion</B></P><P>Our finding suggests that the <I>L. intracellularis</I> vaccine program has effects on the substantial health and economic benefits in the Korean swine industry.</P>

Infrared Thermography Characterization of Defects in Seamless Pipes Using an Infrared Reflector

Park, Hee-Sang,Choi, Man-Yong,Park, Jeong-Hak,Lee, Jea-Jung,Kim, Won-Tae,Lee, Bo-Young The Korean Society for Nondestructive Testing 2012 한국비파괴검사학회지 Vol.32 No.3

Infrared thermography uses infrared energy radiated from any objects above absolute zero temperature, and the range of its application has been constantly broadened. As one of the active test techniques detecting radiant energy generated when energy is applied to an object, ultrasound infrared thermography is a method of detecting defects through hot spots occurring at a defect area when 15~100 kHz of ultrasound is excited to an object. This technique is effective in detecting a wide range affected by ultrasound and vibration in real time. Especially, it is really effective when a defect area is minute. Therefore, this study conducted thermography through lock-in signal processing when an actual defect exists inside the austenite STS304 seamless pipe, which simulates thermal fatigue cracks in a nuclear power plant pipe. With ultrasound excited, this study could detect defects on the rear of a pipe by using an aluminium reflector. Besides, by regulating the angle of the aluminium reflector, this study could detect both front and rear defects as a single infrared thermography image.

Study on Advanced Frequency Estimation Technique using Gain Compensation

Park, Chul-Won,Shin, Dong-Kwang,Kim, Chul-Hwan,Kim, Hak-Man,Kim, Yoon-Sang The Korean Institute of Electrical Engineers 2011 Journal of Electrical Engineering & Technology Vol.6 No.4

Frequency is an important operating parameter for the protection, control, and stability of a power system. Thus, it must be maintained very close to its nominal frequency. Due to the sudden change in generation and loads or faults in a power system, however, frequency deviates from its nominal value. An accurate monitoring of the power frequency is essential for optimum operation and prevention of wide area blackout. Most conventional frequency estimation schemes are based on the DFT filter. In these schemes, the gain error could cause defects when the frequency deviates from the nominal value. We present an advanced frequency estimation technique using gain compensation to enhance the DFT filter-based technique. The proposed technique can reduce the gain error caused when the frequency deviates from the nominal value. Simulation studies are performed using both the data from EMTP-RV software and the user-defined arbitrary signals to demonstrate the effectiveness of the proposed algorithm. Results show that the proposed algorithm achieves good performance under both steady state tests and dynamic conditions.