• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.241-242
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• 1998

For the aritificial heart valve, two types of valves-polymer and mechanical valve- are generally used. The polymer valve is used as a new low-cost artificial valve. Among the several properties of the artificial valve, the low-regurgitation property is important because it can provide better cardiac output characteristic. So in this study we analyzed and compared the regurgitation property of the mechanical valve which is generally used nowdays and the polymer valve which was made in our group. As results, the polymer valve showed the better regurgitation property compared to the mechanical valve approximately by 3 times, and increased the cardiac output by 10%.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.239-240
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• 1998

DTET(Dual Transcutaneous Energy Transmission System) is the stable power transferring unit for TAH(Total Artificial Heart) which uses more power than any other artificial organ. It has better efficiency and safety than an ordinary single TET. By reducing the load, it can reduce the change of supplying current for each single TET and it causes the lower change of efficiency. The increment of magnetic flux in coils enables delivering power through thick skin. It can enable internal batteries remove when will be used in a failure of TET, for a lithium ion battery has heavier weight than TET. A DTET should be studied the effect between each coils that generate magnetic flux. It should be compared the advantage with the weakness when it is used.

• Journal of Digestive Cancer Research
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• v.12 no.1
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• pp.38-43
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• 2024

Artificial Intelligence (AI) is the intelligence of machines or software, in contrast to human intelligence. Generative AI technologies, such as ChatGPT, have emerged as valuable research tools that facilitate brainstorming ideas for research, analyzing data, and writing papers. However, their application has raised concerns regarding authorship, copyright, and ethical considerations. Many organizations of medical journal editors, including the International Committee of Medical Journal Editors and the World Association of Medical Editors, do not recognize AI technology as an author. Instead, they recommend that researchers explicitly acknowledge the use of AI tools in their research methods or acknowledgments. Similarly, international journals do not recognize AI tools as authors and insist that human authors should be accountable for the research findings. Therefore, when integrating AI-generated content into papers, it should be disclosed under the responsibility of human authors, and the details of the AI tools employed should be specified to ensure transparency and reliability.

• Proceedings of the KTCVS Conference
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• 1993.06a
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• pp.124-124
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• 1993

• The Plant Pathology Journal
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• v.20 no.3
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• pp.192-195
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• 2004

A survey on ornamental diseases in 2000 and 2001 showed frequent occurrence of blight symptoms on leaves and stems of columbine and bleeding heart in botanical gardens of Gangwon and Chungnam provinces in Korea. A total of 65 isolates of Streptobotrys sp. were obtained from the infected leaves and stems of the two plants. All isolates were identified as Streptobotrys caulophylli based on their morphological and cultural characteristics. Blight symptoms were induced on leaves of the two plants by artificial inoculation with the isolates. This is the first report that S. caulophylli causes leaf and stem blight on columbine and bleeding heart in the world.

• Journal of Korean Academy of Nursing
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• v.31 no.1
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• pp.31-42
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• 2001

This study was done to evaluate the effect reducing artificial dead space on intubated children. Data were collected from July 1st, 1998 to August 31st, 1999. The subjects were selected from a pediatric intensive care unit of 'S' hospital and intubated with 3.5 mm or 4.5 mm endotracheal tube after open heart surgery. They were composed of 34 patients : 17 patients were assigned to the experimental group and the rest of them were placed in the control group. The artificial airway volume was minimized in the experimental group, and the control group maintained the artificial airway volume. ETCO2, PaCO2, SPO2 were measured as indicators of pulmonary ventilation. The tools of this study were GEM-Premier and Space-Lab patient monitors. The data were analyzed using the SPSS/PC+ program. The $\chi$2 -test was used to find general characteristics. The t-test was used to test the homogenety of the pulmonary ventilation status and mechanical ventilation setting before intervention between the two groups. Also, the paired t-test was used to examine the hypothesis. The results can be summerized as : 1. CO2 can be expelled effectively from the body in case artificial dead space was decreased. 2. As the artificial dead space was reduced, the difference between ETCO2 and PaCO2 was decreased, in other words pulmonary ventilation was improved. 3. If the artificial dead space occupied above 15 percent of tidal volume, the effect of CO2 was retention revealed in the body. 4. If the artificial dead space occupied below effect. Based on the results, the following is suggested to be applied practically : 1. A kind of the ventilator circuit acting artificial dead space should be removed from the intubated children with mechanical ventilaion. 2. The endotracheal tube should not be cut because extra-body space of the endotracheal tube did not have an effect on the dead space of the intubated children. Since the researcher could not cover this aspect in the study, they recommend the following. 1. The study should be extended to the other pulmonary disease patients for the effect of improving pulmonary ventilation. 2. Also, further studying with a more narrow interval in the extra-body space of the artificial airway will be able to explain the point of artificial dead space with proper ventilation.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.1
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• pp.57-66
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• 1996

In this paper, a new biotelemetry system for a transcutaneous data communication between an implanted artificial heart with a control system and an external human-interfaced management system has been developed. A radio telemetry using radio frequency is a commonly used method in the conventional telemetry systems. But, it is not suitable for the medical applications because of not only an interference due to a radio broadcasting but also a harmfulness to the human body. In this paper, therefore, a new biotelemetry system applied to an artificial heart has been developed with the results of the recent research for an optical telemetry system based on the infrared light transmission with good skin permeability. The performance of the biotelemetry system developed has been assessed through mock circulatory experiments, and the clinical applicability has been also confirmed with the successful results in the animal experiments.

• Journal of Biomedical Engineering Research
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• v.24 no.4
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• pp.301-307
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• 2003

In this study, we Presented computational results on the blood flow in the sac of the Korean artificial heart. Two dimensional unsteady flow was assumed and we utilized a finite element commercial code ADINA to simulate the blood flow. Rigid body-solid contact were considered between the actuator and the blood sac and fluid-structure interaction between the blood and the sac. The three geometric models proposed in the design process were simulated to assess the hemodynamic characteristics of the models According to the computational results, a strong flow to the outlet and a stagnated flow region near the inlet were observed during systole. The sac was filled with blood and recirculating flow was generated near the outlet during diastole. Shear stress during systole had its extreme values near the outlet edge whereas the magnitude of shear stress values were relative)v high near the inlet edge and the contacting surface with the actuator.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.5
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• pp.940-947
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• 2006

A variety of actuators fur an implantable artificial heart have been studied. They, all, however, share the disadvantages of a complicated energy conversion mechanism and of the need to use bearings. A ferrofluidic actuator directly drives magnetic fluids by applying a magnetic field to these fluids; it does not require bearings. In this study, the feasibility of a ferrofluidic actuator for an implantable artificial heart was studied. An way of two Poles of ring solenoids was mounted near the acrylic tube $({\phi}\;7.4mm)$. A rubber sack (volume : $2m{\ell}$ was connected to both ends of the acrylic tube. The sack were encased in a rigid chamber that had inlet and outlet ports. The acrylic tube and the rubber sack were filled with water encased in a rigid chamber magnetic fluid and the iron cylinder were immersed in the water. Two experiment method was conducted. 1) distance between stoppers were 72mm and 2) distance between stoppers were 104mm. A stroke volume was stability and $0.96m{\ell}$ was obtained in the experiment 1 and $1.92m{\ell}$ in the experiment 2. The energy efficiency of Experiment method 2 is about five times than Experiment method 2. A magnetic fluid-driven blood pump could be feasible if the magnetic fluid with high magnetization (3 times yester than the current value) is developed.

• The Journal of the Acoustical Society of Korea
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• v.26 no.4
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• pp.144-152
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• 2007

Conventional research works on the classification of the heart sound signal have been done mainly with the artificial neural networks. But the analysis results on the statistical characteristic of the heart sound signal have shown that the HMM is suitable for modeling the heart sound signal. In this paper, we model the various heart sound signals representing different heart diseases with the HMM and find that the classification rate is much affected by the clustering of the heart sound signal. Also, the heart sound signal acquired in real environments is a continuous signal without any specified starting and ending points of time. Hence, for the classification based on the HMM, the continuous cyclic heart sound signal needs to be manually segmented to obtain isolated cycles of the signal. As the manual segmentation will incur the errors in the segmentation and will not be adequate for real time processing, we propose a variant of the ergodic HMM which does not need segmentation procedures. Simulation results show that the proposed method successfully classifies continuous heart sounds with high accuracy.