• 한국태양에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.409-414
• /
• 2009

Since cryogens are stored at very low temperatures, the cryogenic storage systems are quite sensitive to heat leaks. Even though the vessel operated under sealed condition with vacuum insulation and reflective coatings are used, the heat leakage into the vessel is still unavoidable. Therefore, this paper concerns with numerical study of self-pressurization used to analysis the optimum design with the variation volume fraction, effect of heat flux and storage pressure of liquid nitrogen. The result shows that as the volume fraction increases, the pressure rise reduces and the relatively at atmosphere pressure is better than the higher one. In addition, higher heat flux leads the pressure rise increases faster than low one. The additional of heat pipe system to reduce the pressure rise rate also has been done. By this comparison, the optimum design for storage umbilical cord blood can be selected.

• Journal of Pharmacopuncture
• /
• v.20 no.1
• /
• pp.23-28
• /
• 2017

Objectives: Exercise with partially restricted blood flow is a low-load, low-intensity resistance training regimen which may have the potential to increase muscle strength in the obese, elderly and frail who are unable to do high-load training. Restricted blood flow exercise has also been shown to affect blood vessel function variably and can, therefore, contribute to blood vessel dysfunction. This pilot study tests the hypothesis that unilateral resistance training of the leg extensors with partially restricted blood flow increases muscle strength and decreases vascular autoregulation. Methods: The subjects were nine normotensive, overweight, young adult African-Americans with low cardiorespiratory fitness who underwent unilateral training of the quadriceps' femoris muscles with partially restricted blood flow at 30% of the 1-repetition maximum (1-RM) load for 3 weeks. The 1-RM load and post-occlusion blood flow to the lower leg (calf) were measured during reactive hyperemia. Results: The 1-RM load increased in the trained legs from $77{\pm}3$ to $84{\pm}4 kg$ (P < 0.05) in the absence of a significant effect on the 1-RM load in the contralateral untrained legs (P > 0.1). Post-occlusion blood flow decreased significantly in the trained legs from $19{\pm}2$ to $13{\pm}2mL{\cdot}min^{-1}{\cdot}dL^{-1}$ (P < 0.05) and marginally in the contralateral untrained legs from $18{\pm}2$ to $16{\pm}1mL{\cdot}min^{-1}{\cdot}dL^{-1}$ (P = 0.09). Changes in post-occlusion blood flow to the skin overlying the trained and the contralateral untrained muscles were not significant. Conclusion: These results demonstrate that restricted blood flow exercise, which results in significant gains in muscle strength, may produce decrements in endothelial dysfunction and vascular autoregulation. Future studies should determine whether pharmacopuncture plays a role in treatments for such blood vessel dysfunction.

• Journal of Pharmacopuncture
• /
• v.8 no.3
• /
• pp.11-19
• /
• 2005

Objectives : This study focused on how the modem blood vessel is defined in Oriental medicine through literary investigation. Methods : Contents from 35 classical texts representing each era were analyzed for the expression of Hyeolmaek and affiliate information, as well as terms used for the current concept of blood vessel. Results : Following results were obtained through investigating literary information on Hyeolmaek. 1. In the Yellow Emperor's Classic, Hyeolmaek is associated with heart and widely used for physiological, pathological, diagnosis, and treatment purposes. 2. During the Song Dynasty, a term Cheonggeun (靑節). is used to describe the vein in the abdomen. 3. During the Ming Dynasty, terms such as Cheonggeun(靑節) and Cheongmaek(靑脈) were used. 4. The term Hyeolmaek was used inclusively for blood, blood vessels, arteries, veins, and as well as meridians.

• Journal of the Korean Society of Visualization
• /
• v.14 no.1
• /
• pp.33-39
• /
• 2016

Radio-cephalic arteriovenous fistula(RC-AVF) is the most recommended operation of achieving access for hemodialysis. However, it has high rates of early failure depending on the many haemodynamic conditions. To increase RC-AVF patency rate, many researches were performed by in-vitro experiment via artificial vessel and blood analogue fluid, and there were conflicting opinions about whether the non-Newtonian properties of blood have an influence on the flow in large arteries. To investigate the influence of viscoelasticity of blood within the RC-AVF, we fabricated three dimensional artificial RC-AVF and two kinds of blood analogue fluid. The velocity field of two fluids within the vessel were measured by micro-particle velocimetry(m-PIV) and compared with each other. The velocity profiles of both fluids for systolic phase were matched well while those for diastolic phase did not correspond. Therefore, it is desired to use non-newtonian fluid for in-vitro experiment of RC-AVF.

• The Journal of Korean Institute of Information Technology
• /
• v.17 no.5
• /
• pp.77-82
• /
• 2019

Diabetic retinopathy is a complicated form of diabetes due to circulatory disorder in the peripheral blood vessels of the retina. We segment the microvessel for diagnosing diabetic retinophathy. The conventional methods using filter and features can segment the thick blood vessels, but it has relatively weak for segmenting fine blood vessels. In pre-processing step, noise reduction filter and histogram equalization are applied to suppress the noise and enhance the image contrast. Then, deep learning technique is used for pixel-by-pixel segmentation. The accuracy of conventional methods is between 90% to 94%, while the proposed method has improved as 95% accuracy. There is a problem of segmentation error around the optic disc and exudate due to the network depth. However the accuracy can be improved by modifying the network architecture in the future.

• Biomedical Science Letters
• /
• v.28 no.4
• /
• pp.322-326
• /
• 2022

The purpose of this study was to develop hydrolysate from silkworm (Cudrania Silkworm Fibroin Peptide; CSFP), a food containing components for improving blood vessel health. In general, Cudrania tricuspidata leaves contain about 5 times more rutin and 25 times more dihydroquercetin than mulberry leaves. 1-Deoxynojirimycine (1-DNJ), dihydroquercetin and rutin inhibit the activity of carbohydrate-digesting enzymes, inhibit blood lipid peroxidation, and regulate insulin secretion, which helps blood vessels to be healthy. When the diet-controlled silkworm was enzymatically hydrolyzed, it was confirmed that rutin content was about 8 times higher than that of the in general silkworm as a control. In the silkworm hydrolysate, CSFP, developed as a final food material, the active ingredients were 65 mg/kg for rutin, 3,328 mg/kg for DNJ, 0.43 mg/kg for dihydroquercetin, and 82,624 mg/kg for total polyphenol, which was confirmed through LC-MS/MS analysis. In conclusion, it was found that silkworms fed with C. tricuspidata leaves as a diet had more active components that can help control blood sugar and improve blood vessel health than silkworms fed with mulberry leaves.

• Journal of KIISE:Software and Applications
• /
• v.29 no.3
• /
• pp.202-210
• /
• 2002

During the last few years, the extraction and reconstruction of the blood vessels in the medical image has been actively researched and the analysis for the retinal vessel structure has provided important information for diagnosis and remedy of the retinopathy patients. In this research, we propose the algorithm that tracks automatically the entire retinal vessel in retinal image acquired by the ICG(IndoCyanine Green) technology. This algorithm extracts contours and centers by estimating the local maxima and processing directions and detects bifurcations and junctions by comparing direction components of the local maxima from the gradient magnitude profile of each blood vessel. We present experimental results that the entire blood vessel is automatically reconstructed and is excellent in accuracy and connectivity after applying our algorithm to the ICG retinal images of patients.

• Journal of Food Hygiene and Safety
• /
• v.28 no.3
• /
• pp.195-201
• /
• 2013

In atherosclerosis, blood vessels become sensitive to vessel-constricting agents leading to reduced control in the event of abrupt blood pressure changes. Mulberry trees (Morus alba L., MA) have been claimed to contain various bioactive principles that could possibly prevent atherosclerosis development caused by high cholesterol consumption. In order to examine whether MA feeding can prevent the sensitization of blood vessels, MA leaves were fed to rats for 8 weeks and pressor responses to vasoconstricting agents were assessed. Animals were pithed before blood pressure assessments to eliminate reflex compensation in vessel responses. Feeding diets containing high levels of cholesterol led to potentiated pressor responses to sympathetic nerve stimulation, or to injection of norepinephrine, phenylephrine, angiotensin II and vasopressin in pithed rats. These potentiated pressor responses were prevented in rats fed MA leaf-containing diets at 2 or 10% levels. It was also examined in anesthetized non-pithed rats whether similar cholestrol-related sensitization and MA prevention could be observed. However, high cholesterol-induced sensitization in pressor responses were not observed, suggesting that destruction of central cardiovascular control by pithing must have revealed the sensitization responses. It was concluded that MA leaves seem to be active in preventing abnormal blood vessel reactivity caused by hypercholesterolemia.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.9 no.1
• /
• pp.84-97
• /
• 2005

Background and and purpose : The aim of this study is to define the concept and to arrange symptoms of Blood stasis(瘀血) by review of other thesises, literatures connected with it and reserch trend, in order to making a questionnaire of Blood stasis(瘀血) Methods: By review of other thesises and literatures connected with it, we defined the concept and arranged. symptoms of Blood stasis(瘀血). Results: The concept of Blood stasis(瘀血) is summarized as stasis of blood, pollutant of blood and external blood of vessel. The causes and Symptoms of blood stasis is arranged. Conclusion: Review of literatures led to the selection of 48 items describing blood stasis pattern(瘀血證)

• 한국전산유체공학회:학술대회논문집
• /
• 2008.08a
• /
• pp.65.5-65.5
• /
• 2008