• Journal of the Korean Magnetics Society
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• v.23 no.4
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• pp.130-134
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• 2013

The clip-type pulsimeter equipped with a magnetic sensing Hall device and the most popular body sign of the electrocardiogram (ECG) were investigated in order to analyze the pulse wave velocity (PWV). The PWV simultaneously calculated by means of time difference between the maximum peak of ECG pulse wave and the starting point of radial artery pulse wave, and distance difference between the heart position and the radial wrist position. The PWV analyzed from the clinical data was a wider scope of 5~7 m/s with an average value of 6 m/s. By the prediction of blood vessel's elasticity from the analysis of PWV, it may be useful for developing an oriental-western diagnostic medical signal device for a U-health-care system in the future.

• Journal of the Korean Magnetics Society
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• v.22 no.4
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• pp.130-135
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• 2012

One prototype product of clip-type pulsimeter equipped with magnetic field sensing semiconductor Hall device after one permanent magnet attached "Chwan" position in center of a radial artery was developed. The clip-pulsimeter was composed of the hard ware system measuring to voltage signals. To measure the blood velocity, the radial artery pulsimeter is simultaneously connected the PPG (photoplethysmograph). Analysis and comparison of two pulse waves data has done obtained from a clinical test of forty subjects of 20 ages. The value of a blood velocity simultaneously measured from a radial artery puls wave and PPG is an average value of 0.8m/s. The usage of this research results is possible to store the biomedical signals for health care.

• Journal of the Korea Computer Industry Society
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• v.4 no.12
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• pp.887-900
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• 2003

Many applications require the clustering of large amounts of high dimensional data. Most automated clustering techniques have been developed but they do not work effectively and/or efficiently on high dimensional (numerical) data, which is due to the so-called “curse of dimensionality”. Moreover, the high dimensional data often contain a significant amount of noise, which causes additional ineffectiveness of algorithms. Therefore, it is necessary to look over the structure and various characteristics of high dimensional data and to develop algorithm that support clustering adapted to applications of the high dimensional database. In this paper, we investigate and classify the existing high dimensional clustering methods by analyzing the strength and weakness of each method for specific applications and comparing them. Especially, in terms of efficiency and effectiveness, we compare the traditional algorithms with CLIP which are developed by us. This study will contribute to develop more advanced algorithms than the current algorithms.

• Journal of KIISE:Databases
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• v.29 no.3
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• pp.168-179
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• 2002

In this paper, we investigate video representation techniques that are the foundational work for the subsequent video processing such as video storage and retrieval. A video data set if a collection of video clips, each of which is a sequence of video frames and is represented by a multidimensional data sequence (MDS). An MDS is partitioned into video segments considering temporal relationship among frames, and then similar segments of the clip are grouped into video clusters. Thus, the video clip is represented by a small number of video clusters. The video segmentation and clustering algorithm, VDCluster, proposed in this paper guarantee clustering quality to south an extent that satisfies predefined conditions. The experiments show that our algorithm performs very effectively with respect to various video data sets.

• Journal of radiological science and technology
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• v.47 no.1
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• pp.29-37
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• 2024

This study aims to evaluate the performance of the U-Net based learning model that may vary depending on the histogram equalization algorithm. The subject of the experiment were 17 radiology students of this college, and 1,727 data sets in which the region of interest was set in the thyroid after acquiring ultrasound image data were used. The training set consisted of 1,383 images, the validation set consisted of 172 and the test data set consisted of 172. The equalization algorithm was divided into Histogram Equalization(HE) and Contrast Limited Adaptive Histogram Equalization(CLAHE), and according to the clip limit, it was divided into CLAHE8-1, CLAHE8-2. CLAHE8-3. Deep Learning was learned through size control, histogram equalization, Z-score normalization, and data augmentation. As a result of the experiment, the Attention U-Net showed the highest performance from CLAHE8-2 to 0.8355, and the U-Net and BSU-Net showed the highest performance from CLAHE8-3 to 0.8303 and 0.8277. In the case of mIoU, the Attention U-Net was 0.7175 in CLAHE8-2, the U-Net was 0.7098 and the BSU-Net was 0.7060 in CLAHE8-3. This study attempted to confirm the effects of U-Net, Attention U-Net, and BSU-Net models when histogram equalization is performed on ultrasound images. The increase in Clip Limit can be expected to increase the ROI match with the prediction mask by clarifying the boundaries, which affects the improvement of the contrast of the thyroid area in deep learning model learning, and consequently affects the performance improvement.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.5
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• pp.650-661
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• 2005

Statement of problem: It could be hypothesised that attachments, which provide more retention against vortical and horizontal dislodgement, will be associated with more favorable parameters of oral function. Purpose: This study was to provide data of initial retentive force and retention loss of different bar attachment systems recommended for use with maxillary implant overdentures. Material and method: 4 implants were placed in the anterior region of edentulous maxilla, five different systems of bar attachment were fabricated as follows: cantilevered Hader bar using clips (Type 1), Hader bar using clips without cantilever (Type 2), Hader bar using clip and ERA attachment orange male (Type 3), Hader bar using clip and ERA attachment white male (Type 4), and Bar using magnets (Type 5). Each samples were placed in the universal testing machine for determination of retentive forces(at initial and after every 200 cycles up to 1,000 cycles). Results and Conclusion 1. Attachment type 1 showed the biggest initial retentive force followed by type 3, type 2, type 4, and lastly type 5(P<0.001). 2. After 1,000 cycles of repeated removals of attachments, significant loss of retentive forces was taken place except for attachment type 5. 3. After 1,000 cycles of repeated removals, the loss of retentive force between type 1 and type 2, which used Hader bar and clip attachments. was greater in type 1 that had wider clip formation. And between type 3 and type 4, which used ERA attachments, the loss of retentive force was greater in type 4 that had white male attached (P<0.001). 4. After 1.000 cycles of repeated removals, attachment type 3 showed the biggest retentive force followed by type 2, type 4, type 1 and lastly type. 5. There was no significant difference between attachment type 3 and 4, and type 4 and 1(P<0.001).

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.33-41
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• 1996

The present study was aimed to investigate the role of endothelium-derived nitric oxide (NO) in the control of renin release and to examine if NO is implicated in the development of two-kidney, one clip (2K1C) hypertension. Male Sprague-Dawley rats $(150{\sim}200\; g)$ were constricted at the left renal artery. They were then supplemented with $N^{G}-nitro-L-arginine\;methyl\;ester\;(L-NAME,\; 5mg/100\;mL)$ or with L-arginine hydrochloride (400 mg/100 mL) in the drinking water. The control group was supplied with normal tap water. The sham-clipped rats were operated as in 2K1C rats except for that no clip was made. The kidneys were taken to examine in vitro release of renin at days 7 and 14 following clipping the renal artery. Northern blot analysis was also done to assess the expression of renin gene in the kidney. In sham-clipped rats, L-NAME caused a sustained increase of the blood pressure, whereas L-arginine was without effect. Neither L-NAME nor L-arginine-supplementation significantly affected the development of hypertension in 2K1C rats. Plasma renin concentration (PRC) measured on day 28 did not significantly differ among the L-NAME, L-arginine and control groups either in 2K1C or in sham-clipped rats. Renin contents (RRC) in the clipped kidney were increased, while those in the contralateral kidney were decreased. The release of renin in vitro from cortical slices was also enhanced in the clipped kidney, whereas it was attenuated in the contralateral. Comparing the RRC and in vitro release, the latter was more rapidly decreased than the former in the contralateral kidney. The renin mRNA levels in the contralateral kidney were almost at their nadir at days 7 and 14 in 2K1C rats. It is suggested that NO does not affect the development of 2K1C hypertension in which the renin-angiotensin system has been activated. The data also confirm that RRC and renin gene expression are increased in the clipped kidney and suppressed in the contralateral kidney in 2K1C rats.

• Journal of Korean Elementary Science Education
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• v.43 no.1
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• pp.170-184
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• 2024

This study focused on the practical research needed to improve elementary school science lesson plans. Specifically, a video clip-based pedagogical reasoning activity that included elementary student misconceptions was presented and the influences of this activity on preservice teachers' science lesson planning were assessed. First, the eight preservice teacher participants were asked to write a lesson plan for a dissolution and solution unit, after which a first semi-structured interview was conducted. Then, the participants participated in a video clip-based pedagogical reasoning activity. Based on the activity results, the participants revised their previously planned lessons, and second semi-structured interviews were conducted. The data from the preservice teachers' lesson plans and interview transcripts were analyzed using a constant comparative method to investigate the lesson plan changes. It was found that after the video clip-based pedagogical reasoning activity, the preservice teacher tightened the activity or changed the material to understand the students' thinking processes. In addition, they supplemented their goals and assessment criteria to accommodate the diverse students' thinking. Some also specified motivational strategies that considered student interests, motivation, and possible misconceptions. However, some preservice teachers still set goals that did not sufficiently account for student misconceptions and some planned the student assessments based only on the learning goals rather than the students' thinking. The few preservice teachers were able to develop motivational strategies that considered interest, motivation, and misconceptions. The preservice teachers claimed that they had difficulty predicting the misconceptions and connecting these to the lesson content. Discussions were then held to assist the preservice teachers to consider possible student misconceptions when planning their lessons.

• Journal of Magnetics
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• v.19 no.3
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• pp.255-260
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• 2014

A portable clip-type pulsimeter equipped with a magnetic sensing Hall device has been developed to raise the accuracy of oriental disease diagnosis and therapy by convergence of magnetism and oriental medicine. To improve accuracy and reliability of conventional pulsimeter due to subjective analysis of the pulse wave and measuring position dependency of the arterial pulse sensor, the fuzzy algorithm was applied to analyze the strong- and weak-pulse wave symptom. Optimal time for electronic acupuncture was calculated using fuzzy rules and interference were drawn from objective data in view of pre-treatment. Moreover, the electrical characteristics of the pain parts that respond to acupuncture point were applied in view of post-treatment to propose the scientific pulse wave algorithm and simulation experiment.

• Journal of Broadcast Engineering
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• v.5 no.1
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• pp.41-49
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• 2000

In this paper, we propose a new method of indexing and searching based on object-specific features at different semantic levels for video retrieval. A moving trajectory model is used as an indexing key for accessing the individual object in the semantic level. By tracking individual objects with segmented data, we can generate motion trajectories and set model parameters using polynomial curve fitting. The proposed searching scheme supports various types of queries including query by example, query by sketch, and query on weighting parameters for event-based video retrieval. When retrieving the interested video clip, the system returns the best matching event in the similarity order.