• Journal of Fisheries and Marine Sciences Education
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• v.26 no.2
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• pp.401-420
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• 2014

This study aims to analyze middle school students' systemic thinking to express organic relations between different organ systems about the movement of food and air and teachers' reflective thinking about science teaching through their reflective journals after the lesson of digestion, circulation, respiration and excretion. Firstly, when investigating the moving route of hamburger eaten inside the body, students expressed the names, locations and forms of organs in the digestive system more than those in the circulatory system or the excretory system. When investigating the moving route of a painkiller taken inside the body, students seemed to have more difficulty in expressing the related organ systems than when investigating the moving route of other things, and they mostly drew pictures of organs in the digestive system as done for the moving route of hamburger. However, when investigating the moving route of water drunk inside the body, students mostly described organs in the digestive system but drew more pictures of organs in the excretory system, than when investigating the moving route of other things. When investigating the moving route of air inhaled inside the body, students mostly drew pictures of organs in the respiratory system, but the rate of their drawing pictures of circulatory organs was low. Secondly, this study analyzed one of the teachers' reflective journals, named Mr. Park. According to his journal, students showed different levels of understanding of organ names, depending on their degrees of familiarity with each organ, and in regard to the locations of organs, science teachers mostly aim to achieve learning objectives so much that they often forget to instruct the locations of organs in fact. As for the forms of organs, science teachers mostly spend so much time explaining the functions of organs that they often forget to describe the exact form of each organ.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.2
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• pp.76-81
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• 2006

This paper analysed the characteristics of current density induced inside human body by 60 Hz extremely low frequency magnetic fields according to varying conductivities of human model. Human model was composed of several organs and other parts, whose shapes were expressed by spheroids or cylinders. Organs such as the brain, heart, lungs, liver and intestines were taken into account. Applying the boundary element method to the human model, we estimated effects on the induced current distribution due to differences of the organ conductivity and shape. We find organ conductivity influences most and a cross section area and a position of organ also gives effects.

• Proceedings of the KIEE Conference
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• summer
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• pp.581-583
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• 2004

This paper analysed the induced current density characteristics inside human body by extremely low frequency magnetic fields according to varying conductivities of human model. Human model was composed of several organs and other parts of 곳 human body, whose shapes were spheroids or cylinders. Organs taken into account were the brain, heart, lungs, liver and intestines. Applying the boundary element method to the human model, effects of the organ conductivity difference to the induced current distribution were estimated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.161-162
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• 2007

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.90-93
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• 2002

In particle radiotherapy, a shape of the beam to conform the irradiation field is statically defined by the compensator, collimator and potal devices at the outside of the patient body. However the target such as lung or liver cancer moves along with respiration. This increases the irradiated volume of normal tissue. Prior discussions about organ motions along with respiration have been mainly focused on inferior-superior movement that was usually perpendicular to beam axis. On the other hand, the change of the target depth along the beam axis is very important especially in particle radiotherapy, because the range end of beam (Bragg peak) is so sharp as to be matched to distal edge of the target. In treatment planning, the range of the particle beam inside the body is calculated using a calibration curve relating CT number and water equivalent path length (WEL) to correct the inhomogeneities of tissues. The variation in CT number along the beam path would cause the uncertainties of range calculation at treatment planning for particle radiotherapy. To estimate the uncertainties of the range calculation associated with patient breathing, we proposed the method using sequential CT images with respiration waveform, and analyzed organ motions and WELs at patients that had lung or liver cancer. The variation of the depth along the beam path was presented in WEL rather than geometrical length. In analyzed cases, WELs around the diaphragm were remarkably changed depending on the respiration, and the magnitude of these WEL variations was almost comparable to inferior-superior movement of diaphragm. The variation of WEL around the lung was influenced by heartbeat.

• Korean Journal of Veterinary Research
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• v.28 no.1
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• pp.145-154
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• 1988

Ixodes signatus nymphs were subjected to the scanning electron microscopy for the observation of the major physiological sense organs including the Hailer's organ. Finger prints and variable sensory setae were found on the body surface, and especially well developed setae were identified on the article IV and on the anal lobes. A central button-like organelle and numerous small holes were found in the spiracular plate. The Haller's organ was identified at the distal point of the tarsus I and regarded as the major sensory organ, chemoreceptor. Tow types of sensory setae were observed, the shorter ones in front of the organ and the longer ones in distal front as well as near behind of the organ. The fully opened organ was ellipsoidal and a total of seven basiconic sensory pegs rooted deeply and shaped as well arranged hook-like was found inside the organ.

• Applied Microscopy
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• v.8 no.1
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• pp.67-76
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• 1978

A comparative investigation of fine structure of callus cells derived from tissue culture of Panax ginseng was made by electron microscope. Callus was consisted of large superficial cells and small inner zone cells derived from shoot apex tissue cultured for 16 weeks. Large superficial cells were contained the clusters of starch grains surrounded by a double plastid membrane. Especially, electron dense particles were deposited just inside and outside of plastid membrane and also deposited on mitochondria-like and endoplasmic reticulum-like structures. Crystalline body was also found in superficial cells. Small inner zone cells were characterized by presence of proplastids sheathed by short endoplasmic reticulum profiles. presence of spiral configuration of ribosomes and absence of crystalline body. Organ primordia was consisted of a dense cytoplasm and notable nucleate cells derived from nodal tissue cultured for 67 weeks. Proplastids containing starch grains and crystalline bodies were frequently observed; starch grains are of small quantity and does not form the clusters as in inner zone cells; hexagonal crystalline body itself does not have always limiting membrane. Remarkably. in a few cells of primordia, particles resembling the presumptive virus were observed mainly in condensed nuclear chromatin and also in cytoplasm, in mitochondrion-like organelle.

• Journal of Mechanical Science and Technology
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• v.20 no.7
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• pp.1012-1018
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• 2006

Diagnosis and treatment using the conventional flexible endoscope in gastro-intestinal tract are very common since advanced and instrumented endoscopes allow diagnosis and treatment by introducing the human body through natural orifices. However, the operation of endoscope is very labor intensive work and gives patients some pains. As an alternative, therefore, the capsule endoscope is developed for the diagnosis of digestive organs. Although the capsule endoscope has conveniences for diagnosis, it is passively moved by the peristaltic waves of gastro-intestinal tract and thus has some limitations for doctor to get the image of the organ and to diagnose more thoroughly. As a solution of these problems, various locomotive mechanisms for capsule endoscopes are introduced. In our proposed mechanism, the capsule-type microrobot has synchronized multiple legs that are actuated by a linear actuator and two mobile cylinders inside of the capsule. For the feasibility test of the proposed microrobot, a series of in-vitro experiments using small intestine without incision were carried out. From the experimental results, our proposed microrobot can advance along the 3D curved and sloped path with the velocity of about $3.29\sim6.26mm/sec$ and $35.1\sim66.7%$ of theoretical velocity. Finally, the proposed locomotive mechanism can be not only applicable to micro capsule endoscopes but also effective to advance inside of gastro-intestinal tract.

• Journal of Biomedical Engineering Research
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• v.14 no.3
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• pp.243-250
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• 1993

An endoscope is a medical device which observes the inner surface of an organ inside a body. Recently, a new type of endoscope using a CCD image sensor has been developed and turned out to have many strong points over the conventional optical fiber endoscope system. A swallowable insertion tube is an insertion tube having so small a diameter that the head of the insertion tube can reach the end of stomach only by mechanical movement of the esphagus and stomach or the patient's external movement. This paper presents some of the results that the Institute of Biomedical Engineering at Seoul National University has obtained while developing an electronic endoscope having a swallowable insertion tube. After some of the features of the developed system are presented, some of the image processing techniaues are addressed.

• International journal of advanced smart convergence
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• v.7 no.4
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• pp.169-173
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• 2018

Iris diagnosis based on the color and texture information is one of a novel approach which can represent the current state of a certain organ inside body or the health condition of a person. In analysis of the iris images, there are critical image artifacts which can prevent of use interpretation of the iris textures on images. Here, we developed the iris diagnosis system based on a hand-held typed imaging probe which consists of a single camera sensor module with 8M pixels, two pairs of 400~700 nm LED, and a guide beam. Two original images with different light noise pattern were successively acquired in turns, and the light noise-free image was finally reconstructed and demonstrated by the proposed artifact removal approach.