• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.43-49
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• 2008

The evaporation heat transfer coefficient and pressure drop of R-22 and R-407C in horizontal copper tubes were investigated experimentally. The main components of therefrigerant loop are a receiver, a compressor, a mass flow meter, a condenser and a double pipe type evaporator (test section). The test section consists of a smooth copper tube of 4.3 mm and 6.4 mm inner diameter. The refrigerant mass fluxes were varied from 100 to $300[kg/m^2s]$ and the saturation temperature of evaporator were 5 [$^{\circ}C$]. The evaporation heat transfer coefficients of R-22 and R-407C rise with the increase in mass flux and vapor quality. The evaporation heat transfer coefficient of R-22 for inner diameter tube of 4.3 mm and 6.4 mm is about $7.3{\sim}47.1%$ and $5.68{\sim}46.6%$ higher than that of R-407C, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1307-1312
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• 2007

The flow characteristics of R-134a in a small diameter tube was investigated experimentally. An experimental apparatus was consisted of a magnetic gear pump, an evaporator, a sight-glass, a condenser and a measurement instruments. The sight-glass for flow pattern observations was located at the inlet and outlet of the evaporator. The experiment was carried out to show the flow characteristics of R-134a in a small diameter tube. Mass flux of refrigerants was ranged from 100 to 1000 $kg/m^2s$, the saturation temperature was $30^{\circ}C$. In the flow patterns during evaporation, the annular flow in a 2 mm inner diameter tube occurred at a relatively lower quality and mass velocity, compared to that in a 8 mm inner diameter tube. The evaporation flow pattern in a small diameter tube has been shown major deviations with the Baker, Mandhane and Taitel-Dutler's flow pattern maps but it was similar to the Dobson's flow pattern map.

• The Korean Journal of Pain
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• v.21 no.2
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• pp.112-118
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• 2008

Background: This study was conducted to quantitatively analyze proteins associated with the calcitonin gene-related peptide (CGRP) in cerebrospinal fluid (CSF) that was obtained from a rat model of chronic neuropathic pain following administration of intrathecal $CGRP_{8-37}$. Methods: Male Sprague-Dawley rats (100-150 g, 5-6 wks) were divided into two groups, sham controls and neuropathic pain models. At the time of operation for neuropathic pain model, an intrathecal catheter was threaded through the intrathecal space. At 1 or 2 wks after the operation (maximum pain state), a test dose of 1, 5, 10, or 50 nM of $CGRP_{8-37}$ was injected into the intrathecal catheter and the CSF was then aspirated. Conventional proteomics to evaluate the CSF were then performed using high resolution 2-D, gel electrophoresis followed by computational image analysis and protein identification by mass spectrometry. Results: Treatment with $CGRP_{8-37}$ effectively alleviated mechanical allodynia in a dose dependent manner. The most effective response was obtained when a dose of 50 nM was administered, but significant differences were obtained following administration of only 5 nM $CGRP_{8-37}$. Furthermore, the results of the proteomic analysis were consistent with the experimental results. Specially we detected 30 differentially expressed spots in 7 images when 2-D gel electrophoresis was conducted. The intensity of 6 of these spots (spot number: 20 and 26-30) was found decrease the $CGRP_{8-37}$ dose increased; therefore, these spots were evaluated by mass spectrometry. This analysis identified 2 different proteins, CGRP (spot numbers: 26-30) and neurotensin-related peptide (spot number: 20). Conclusions: The results of this study suggest that CGRP plays a role in chronic central neuropathic pain and is a major target of chronic neuropathic pain management.

• Journal of Sensor Science and Technology
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• v.5 no.3
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• pp.65-73
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• 1996

One of the important factor in drug stuffs to a patient is to inject exact amount with stable flow rates. Since improper injection amount and flow rates would cause bad effect to recovery of a patient, the detecting sensors with high sensitivity is required for an injection pump systems' performance improvement. In this study, the three sensors, piezo film sensor, photo transistor and photo array, were compared to find best one for an injection pump monitoring system. Using suggested data processing technique and photo array sensors, we could minimize the effect of interference, disturbance, illumination, and sensitivity change caused by sensor's position. According to the experiments, the photo array showed the higher reliance than any other the three types of sensors.

• Journal of Sensor Science and Technology
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• v.24 no.2
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• pp.113-118
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• 2015

Intravenous (IV) infusion set is one of the most common treatment methods applied to hospitalized patients. However, it is necessary to check the injection of IV solution in order to prevent patients from any possible medical injuries. In this paper, using the optical sensors to detect exhaustion of IV solution was proposed. The optical sensor is coplanar structure composed of LED and photodiode which is installed according to focal distance of the lens. These two elements detect exhaustion of IV solution at the desired point conveniently. Through the results of experiments using various wavelength of LED (R.G.B), the blue LED was selected to the optimum light source. The suggested optical sensor can detect exhaustion of IV solution by the differences in the amount of light which is caused by properties such as total reflection, refractive index and scattering. From the implementation, the detector is applicable to both containers of IV solution, glass bottle and plastic pack. And also the result shows apparent differences according to existence of IV solution even if the IV solution color and illumination were changed.

• Journal of Chest Surgery
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• v.32 no.9
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• pp.835-839
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• 1999

Since the first report of coronary artery bypass grafting (CABG) in patients with end-stage renal disease in 1974, numerous reports have documented the feasibility of CABG in patients with chronic renal diseases. Patients with chronic renal failure often have comorbid disorders such as hypertension, and diabetes mellitus, each with their own complications and associated impact on both short and long-term survivals. In addition, infection and sepsis have been identified as significant causes of morbidity and mortality in most series of patients with end-stage renal disease undergoing cardiac surgical procedure. As a result of these and other factors such as perioperative volume and electrolyte disturbances, patients with chronic renal failures are at an increased risk of complication and mortality after CABG. We report 3 cases of "Off-pump" CABG in the chronic renal failure patients. patients.

• Journal of Chest Surgery
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• v.29 no.12
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• pp.1401-1404
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• 1996

Central venous line insertion is an essential procedure in a cardiac operation. For this, percuteneous Insertion is usually done in the internal jugular vein or the subclavian vein. However, this method can create such complications as pneumothorax and hemothorax, and repeated failure in inserting the cathet r, especially in infant and child patients, can waste excessive time. Consequently, in our hospital, catheterization of the innominate vein was done after the completion of sternotomy in the cardiac operation of infant and child patients weighing under 1 Okg. During operation, the catheter was placed in the left atrium through the foramen ovate or pulmonary artery to be used for pressure monitoring. When the patient's hemodynamic became stabilized, the catheter was withdrawn to either the right atrium or superior vena casa to be used as the channel for fluid replacement or drug administration. In our hospital, this procedure has been used in 96 cases since 1989. No complications such as pneumothorax and hemothorax occilrred, and neither bleeding after the removal of the catheter was seen.

• Korean Journal of Veterinary Research
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• v.21 no.1
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• pp.11-23
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• 1981

서울 경마장(競馬場)의 경주마(競走馬) 517두를 대상으로 호흡기병상(呼吸器症狀)을 관찰하여 1978년 12월 중순(中旬)부터 1979년 1월 초순(初旬) 까지 42.9%의 호흡기병상발생률(呼吸器症狀發生率)을 보았고 1979년 1월 하순(下旬)부터 5월 중순(中旬)까지 임신마(姙娠馬)의 60%가 사산(死産)을 일으켰다. 사산(死産)된 태자(胎仔)는 육안적(肉眼的)으로 흉강수액(胸腔水液)의 저류, 각 장기(臟器)의 울혈성수종(鬱血性水種), 출혈성병변(出血性病變)과 간장(肝臟)의 소상괴사(巢狀壞死)를 나타내었고, 조직학적(組織學的)으로는 간장(肝臟)의 한국성괴사소(限局性壞死巢), 비장(脾臟), 임파절(淋巴節), 흉선(胸線)과 Peyer판(板)에서의 세강(細網) 세포(細胞)의 증식성(增殖性), 괴사성변화(壞死性變化)와 임파양세포(淋巴樣細胞)의 붕괴(崩壞)를 시현(示顯)하였다. 여기서 간세포(肝細胞), 담관상피세포(膽管上皮細胞), 소기관지상피세포(小氣管支上皮細胞) 및 비장(脾臟), 임파절(淋巴節), 흉선(胸線)의 세강(細網) 세포(細胞)에서 Cowdry type A 봉입체(封入體)를 확인하였다. 이상의 역학적(疫學的) 및 병리학적(病理學的) 소견(所見)에 의하여 본(本) 마유산증(馬流産症)을 말 바이러스성 비폐염(鼻肺炎)이라고 진단(診斷)할 수 있었으며 본(本) 발병예(發病例)가 한국(韓國)에서 초발생(初發生)인 것으로 추정(推定)되었다.

• Journal of the Korean Society of Radiology
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• v.7 no.4
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• pp.265-269
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• 2013

This report aims at picturing out the clinical usefulness by analyzing the signal intensity in choroid plexuses which produce cerebrospinal fluids by diffusion weighted imaging. At first, subjects were chosen among the patients who showed high in signal intensity by diffusion weighted imaging. The subjects were taken another test by fluid attenuated inversion recovery diffusion weighted echo planer image(FLAIR-DW-EPI) the signals of fluid attenuation. And it was found that there are differences between the signal intensities of the two methods, which showed that the signal intensity in FLAIR-DW-EPI is equal to or low than, that in the Brain. By this, it is felt that it is helpful to diagnose the disease in choroid plexus by testing another more with FLAIR-DW-EPI methods the patients who showed high in signal intensity in choroid plexus by $T2^*$ diffusion weighted echo planer image($T2^*$-DW-EPI).

• Pediatric Infection and Vaccine
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• v.25 no.1
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• pp.45-49
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• 2018

Group B streptococcus (GBS) is the leading cause of neonatal morbidity and mortality. Late-onset GBS disease commonly manifests as occult bacteremia or meningitis. Approximately 50% of survivors of late-onset meningitis have long-term neurologic sequelae. Cerebrovascular complications are often associated with unfavorable clinical outcomes of GBS meningitis. There have been a few reports of cerebral infarction accompanied by GBS meningitis. We report a 29-day-old girl with severe, widespread cerebral infarction due to late-onset GBS meningitis. Isolated GBS strain from this patient was serotype III, ST-19. Currently, she has cortical blindness and significant developmental delay.