• 한국임상수의학회지
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• 제14권2호
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• pp.297-300
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• 1997

Artificial insemination with frozen canine semen using vaginal endoscope was performed in a two years old Golden Retriever to investigate the feasibility of this technique. The bitch was in her second estrus. Blood progesterone concentration was evaluated every two days to decide the timing of insemination since vaginal bleeding was observed. Insemination was performed twice in 48 hours interval on the fourth and sixth posterior to LH surge, respectively. The volume of frozen semen injected was 1.5 ml $(1{\times}10^{8}$ sperms/1ml of semen). The bitch was pregnant and she whelped a female pup on sixty one days after first insemination.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2000년도 춘계 학술대회논문집
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• pp.27-32
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• 2000

In this study, the three-dimensional blood flow within the sac of KTAH(Korean artificial heart) is simulated using fluid-structure interaction model. The numerical method employed in this study is the finite element commercial package ADINA. The thrombus formation is one of the most critical problems in KTAH. High fluid shear stress or stagnated flow are believed to be the main causes of these disastrous phenomenon. We solved the fluid-structure interaction between the 3D blood flow in the sac and the surrounding sac material. The sac material is assumed as linear elastic material and the blood as incompressible viscous fluid. Numerical solutions show that high shear stress region and stagnated flow are found near the upper part of the sac and near the comer of the outlet during diastole stage.

• The Korean Journal of Physiology
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• 제26권1호
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• pp.37-44
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• 1992

The encapsulation of the Purified bovine hemoglobin with Phospholipids obtained from egg folk was performed using a rotary vacuum evaporator. The prepared Hb-containing liposome (hemosome) had good properties as artificial red blood cell. The shape and size of the hemosomes were measured by a phase contrast microscope and image analyzer. The function of the hemosome as oxygen carrier was tested by measuring oxygen saturation curve with blood gas analyzer and infusing it into rats. The prepared hemosome was 1.184 + 0.423 ${\mu}m$ in diameter and round in shape. $P_{50}$ value of the hemosome solution was 28 mmHg. The synthesized red cells seem to function as oxygen carrier, because the severely bled rats were prolonged in their life by transfusion of the hemosome solution containing bovine hemoglobin.

• 대한전기학회논문지
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• 제34권7호
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• pp.257-266
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• 1985

A new method for the artificial beta cell which can be used to control the hyperglycemia in diabetic patients was represented. The relationship between the insulin infusion rate and the blood glucose concentration was described by the second order ARMA model, and the time varying parameters were identified by exponentially weighted least squares estimator. The design of controller was based on the pole assignment self tuning altorithm with discrete blood sampling and the constraints of input and output responsse rate were considered. The results of animal experiments show that this method may be a fruitful approach for regulating the blood glucose level. We expect that this device can be used as both therapeutic and research tools providing that its stability and reliability are improved a little more.

• Journal of Chest Surgery
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• 제27권10호
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• pp.824-832
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• 1994

Recently we developed the concept of totally implantable electrohydraulic artificial heart. We tested the artificial heart which was drived by external compressive air in the calves. All three calves had pneumonia before surgery, so postoperative course was not only bad but also the results was not good. The first calf died severe pneumonia on 76th day, the second calf died from troublesome bleeding and uncertain allergic like reaction, and the third died because of bleeding. However, the performance of the artificial heart was good, and especially the blood contacting surface showed excellent hemocompatibility. The anatomic fitting was also very good even in the 35 Kg small newborn calf. During treadmill test, the first calf did not well tolerate for 1 minute but by the Full Fill Full Empty control method the artificial heart responsed well to the physiologic needs. In conclusion, the artificial heart had the very good hemocompatible surface, however, the volume of the artificial heart was a little deficient for the calf and the control algorithm needed further development.

• International Journal of Control, Automation, and Systems
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• 제5권6호
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• pp.643-651
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• 2007

The various blood pressure simulators have been proposed to evaluate and improve the performance of the automatic sphygmomanometer. These have some problems such as the deviation of the actual blood pressure waveform, limitation in the blood pressure condition of the simulator, or difficulty in displaying the blood flow. An improved simulator using disturbance observer is proposed to supplement the current problems of the blood pressure simulator. The proposed simulator has an artificial arm model capable of feeding appropriate fluids that can generate the blood pressure waveform to evaluate the automatic sphygmomanometer. A controller was designed and thereafter, simulation was performed to control the output signal with respect to the reference input in the fluid dynamic model using the proposed proportional control valve. To minimize the external fluctuation of pressure applied to the artificial arm, a disturbance observer was designed on the plant. A hybrid controller combined with a proportional controller and feed-forward controller was fabricated after applying a disturbance observer to the control plant. Comparison of the simulations between the conventional proportional controller and the proposed hybrid controller indicated that even though the former showed good control performance without disturbance, it was affected by the disturbance signal induced by the cuff. The latter exhibited an excellent performance under both situations.

• Asian-Australasian Journal of Animal Sciences
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• 제24권9호
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• pp.1192-1198
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• 2011

Peri-partum metabolic profile was evaluated in winter and summer calving, with 15 Murrah buffaloes in each seasonal group. In summer calvers, significantly lower values were observed for blood plasma urea nitrogen (BUN) at day 30 pre-partum (p<0.05), on calving day (p<0.05) and at all other stages (p<0.01); plasma non-esterified fatty acids (NEFA) values were significantly lower on day 30 pre-partum (p<0.01) and on day 60 post-partum (p<0.05). This was associated with significant reduction in days to first service (DFS) and service per conception (SPC) and an overall better reproductive performance in terms of service period, risk to first service on days 60, 90 and >90, and pregnancy risk to first service up to days 60 and 90. This may be attributed to better pre-partum nutritional status. Cervical and uterine involution were completed in fewer days, involutional changes took place at a faster pace and there were a lower number of abnormal involutional changes in winter compared to summer season. This may be attributed to better post-partum nutrition and less environmental stress. However, validation requires further targeted cohort investigation with a large sample size.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.703-704
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• 2002

The two major problems related to the blood flow in a floating type polymer valve are thrombus formation and hemolysis. It is well known that the shear stress in the fluid and flow separation around the valve are blamed for such disastrous phenomena. In this viewpoint, through study of the flow field around the valve is imperative to improve design of the valve. The aim of this study is to investigate the fluid flow around a floating type polymer valve. The numerical method employed in this study is the finite element software called ADINA. Incompressible viscous flow is assumed for blood using the assumption of Newtonian fluid. In this study, two prominent features of the axisymmetric flow around the floating type polymer valve are observed: jet-like flows observed near the gap between the conduit and the valve, and recirculating flow downstream of the valve. We also provided a detailed description of shear stress field according to the variation of flow conditions. The shear stress in fluid has its maximum value near the gap between the valve and the conduit.

• Journal of Electrical Engineering and Technology
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• 제7권2호
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• pp.193-199
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• 2012

Worldwide cardiovascular diseases are the major cause of death. Aside from heart transplants, which are limited due to the availability of human donor hearts, artificial hearts are the only therapy available for terminal heart diseases. For various reasons, a total implantable artificial heart is desirable. But the limited space in the human thorax sets rigorous restrictions on the weight and dimensions of the device. Nevertheless, the appropriate functionality of the artificial heart must be ensured and blood damage must be prevented. These requirements set further restrictions to the drive of this device. In the this paper, two optimization methods, namely, the manual parameter variation and Differential Evolution algorithm, are presented and applied to match the specifications of an artificial heart.

• 한국잠사곤충학회지
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• 제39권1호
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• pp.79-85
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• 1997

Bombyx mori, silkworm powder has been studied for blood-glucose lowering activity by National Sericulture & Entomology Research Institute(NSERI) and Kyung Hee University group in 1995. To obtain the optimum preparative condition of silkworm powder for lowering blood-glucose levels in postprandial time, blood-glucose lowering activity of mulberry & silkworm varieties were examined. In mulberry varieties, Samkwangjam showed the highest activity. Activity for lowering blood-glucose levels of autumn rearing silkworm was higher than that of spring silkworm and hybrid silkworm showed higher activity than that of parent silkworm. In the silkworm lines, Chinese lines showed higher activity than that of Japanese lines. In experiments to see the difference in blood-glucose lowering activity between either male and female or larvae and pupae, activity of larvae was higher than that of pupae and the male was higher than female. The heating dry and artificial diet showed lower than mulberry diet and normal freeze dry of the 5th instar 3rd day. Among the sericultural products, larvae showed the highest activity.