• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.1181-1188
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• 2017

The unit and fundamental units of number fields are important to number field sieves testing primality of more than 400 digits integers and number field seive factoring the number in RSA cryptosystem, and multiplication of ideals and counting class number of the number field in imaginary quadratic cryptosystem. To minimize the time and space in H/W implementation of cryptosystems using fundamental units, in this paper, we introduce the Dirichlet's unit Theorem and propose our process of generating the fundamental units of the number field. And then we present the algorithm generating our fundamental units of the number field to minimize the time and space in H/W implementation and implementation results using the algorithm over the number field.

• Proceedings of the SCSK Conference
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• 1999.10a
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• pp.111-121
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• 1999

Acne vulgaris, the most common skin disease. can be formed as only a few comedons or severe inflammatory lesions. The pathogenesis of acne involves various factors; excessive androgen, excessive sebum production, abnormal alteration of follicular epithelium, proliferation of Propionibacterium acnes, and inflammation. We investigated acne therapy using oriental herbs described in the Korean traditional medical book (Dong-ui-bo-gam). Oriental herbs (Angleica daurica. Arctium lappa. Coptidis rhizoma, and glycyrrhiza glabra) were chosen based on their respective property of sebum control, anti-inflammatory activity, and anti-bacterial activity. We examined the effect of acne treatment, in terms of chemotactic inhibition, lipogenesis inhibition, and anti-bacterial activity for P. acnes. 1. Neutrophil chemotaxis assay ; P acnes secrete chemotactic factors and other pro-inflammatory extracellular products. Neutrophil chemotactic activity of P. acnes was measured by 48-well chemotaxis method. Angelica daurica clearly suppressed chemotactic activity of P. acens. 2. Using sebaceous gland of hamster ear lipogenesis assay; Sebaceous lipogenesis was measured using ear biopsies by incubation of $C^{14}$ -acetate in culture media. The $C^{14}$ -labeled lipids were extracted and determined by liquid scintilation counting, Coptidis rhizoma markedly inhibited sebum production, 3. Anti-bacterial assay for P. acnes (MIC test) Glycyrrhiza glabra showed anti-bacterial activity. P. acnes did not develop resistance against Glycyrrhiza glabra. Retinoids are effectively to inhibit sebum production and regulate follicular keratinization process, with little anti-inflammatory activity. Angelica daurica suppressed neutrophil chemotaxis. Coptidis rhizoma inhibited sebum production, and Glycyrrhiza glabra showed anti-bacterial activity against P. acnes. A combined formulation of Angelica daurica. Coptidisr hizoma and Glycyrrhiza glabra is expected to provide effective acne treatment.ent.ive acne treatment.

• Journal of the Korea Concrete Institute
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• v.13 no.2
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• pp.146-152
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• 2001

The fractal geometry is a non-Euclidean geometry which discribes the naturally irregular or fragmented shaps, so that it can be applied to fracture behavior of materials to investigate the fracture process. Fractal curves have a characteristic that represents a self-similarity as an invariant based on the fractal dimension. This fractal geometry was applied to the crack growth of cementitious composites in order to correlate the fracture behavior to microstructures of cemposite composites. The purpose of this study was to find relationships between fractal dimensions and fracture energy. Fracture test was carried out in order to investigate the fracture behavior of plain and fiber reinforced cement composites. The load-CMOD curve and fracture energy of the beams were observed under the three point loading system. The crack profiles were obtained by the image processing system. Box counting method was used to determine the fractal dimension, D$_{f}$. It was known that the linear correlation exists between fractal dimension and fracture energy of the cement composites. The implications of the fractal nature for the crack growth behavior on the fracture energy, G$_{f}$ is appearent.ent.

• School Mathematics
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• v.5 no.3
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• pp.385-399
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• 2003

In our present elementary mathematics curriculum, natural numbers are taught by using the a method of one-to-one correspondence or counting operation which are not related to measurement, and fractional numbers are taught by using a method which is partially related to measurement. The most serious limitation of these teaching methods is that natural numbers and fractional numbers are separated. To overcome this limitation, Dewey and Davydov insisted that the natural number and the fractional number should be taught by measurement of quantity. In this article, we suggested a method of teaching the natural number and the fractional number by measurement of quantity based on the claims of Dewey and Davydov, and compare it with our current method. In conclusion, we drew some educational implications of teaching the natural number and the fractional number by measurement of quantity as follows. First, the concepts of the natural number and the fractional number evolve from measurement of quantity. Second, the process of transition from the natural number to the fractional number became to continuous. Third, the natural number, the fractional number, and their lower categories are closely related.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.345-350
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• 2011

Purpose: Although platelet-rich plasma (PRP) potentiate the wound healing activity of adipose-derived stem cells (ADSCs), its effect cannot be sustained for a prolonged period of time due to short duration of action. This led us to design and produce platelet-rich fibrin (PRF), in an effort to develop a tool which lasts longer, and apply it on wound healing. Methods: Two symmetrical skin defects were made on the back of seven nude mice. ADSCs were applied to each wound, combined with either PRP or PRF. The wound area was measured over 14 days. By day 16, the wound was harvested and histologic analysis was performed including counting of the blood vessel. Results: The healing rate was more accelerated in PRP group in the first 5 days (p<0.05). However, PRF group surpassed PRP group after 6 days (p<0.05). The average number of blood vessels observed in the PRF group was $6.53{\pm}0.51$, compared with $5.68{\pm}0.71$ for the PRP group. Conclusion: PRF exerts a slow yet pervasive influence over the two-week course of the wound healing process. Thus, PRF is probably more beneficial for promoting the activity of ADSCs for a sustained period of time.

• The Mathematical Education
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• v.40 no.2
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• pp.195-215
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• 2001

The purpose of this paper is to present a specific set of home teaching methods in hopes to prevent slow learner of the elementary mathematics. This paper deals with the number and operations, one of five topics in the elementary mathematics A survey of two hundred elementary school teachers was made to see the teacher's opinions of the role of home studying and to concretize the contents of the research topics. There were asked which is the most essential contents for the concrete loaming and which is the most difficult monad that might cause slow leaner. And those were found to be; counting, and arithmetic operations(addition and subtraction) of one or two-digit numbers and multiplication and their concepts representations and operations(addition and subtraction) of fractions. The home teaching methods are based on the situated learning about problem solving in real life situations and on the active teaming which induces children's participation in the process of teaching and learning. Those activities in teaching each contents are designed to deal with real objects and situations. Most teaching methods are presented in the order of school curriculum. To teach the concepts of numbers and the place value, useful activities using manipulative materials (Base ten blocks, Unifix, etc.) or real objects are also proposed. Natural number's operations such as addition, subtraction and multiplication are subdivided into small steps depending upon current curriculum, then for understanding of operational meaning and generalization, games and activities related to the calculation of changes are suggested. For fractions, this paper suggest 10 learning steps, say equivalent partition, fractional pattern, fractional size, relationship between the mixed fractions and the improper fraction, identifying fractions on the number line, 1 as a unit, discrete view point of fractions, comparison of fractional sizes, addition and subtraction, quantitative concepts. This research basically centers on the informal activities of kids under the real-life situation because such experiences are believed to be useful to prevent slow learner. All activities and learnings in this paper assume children's active participation and we believe that such active and informal learning would be more effective for learning transfer and generalization.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.5
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• pp.1121-1129
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• 1988

An economic and efficient system for measuring drop sizes was developed. Pattern recognition technique was used with conventional oil-bath sampling and photographic method. The system was designed to measure and count relatively large number of drops in a very short time, and also to filter out abnormal images such as drops in contact or overlap as well as odd-shaped foreign materials. In this measuring system, most important error originates from the process of converting the original image to the binary image. If the photograph contains a large number of spray drops, the relative size of the pixel to the drops is not infinitesimally small; thus the proper choice of threshold level to convert the original image to the binary image becomes very important. In present case, most of the images lay in one of the two separate bands of brightness level and the arithmetic mean of the most popular brightness levels from each band was chosen as the threshold level. Present image processing system reduces the subjective error by the observers in counting and measuring drops and turns out to be substantially effective. The processing time can be further reduced by improving the hardware system concerned with the digital image coding.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 1996.06a
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• pp.33-33
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• 1996

Interests in the field of rapid methods and automation in microbiology have been growing steadily on an international scale in recent years. International meetings concerned this problem have been held in elsewhere in the world countries since the past twenty years. But, unfortunately in the field of microbial examination in food hygiene, this problem have not yet been developed so much as in the field of clinical microbiology. Today, I would like to introduce you here present aspects of rapid and automation technologies, those which are manly carrying in milk and meats industries. My illustration will be given recent improved technologies using automatic apparatus and instruments along with process of microbial count procedure. Recent direct microbiological counting system (ChemeScan \ulcorner) as real time ultrasensitive analysis created by Cheminex Ltd., France is now most evolutional instrument to provide direct microbial counts, down to one cell, within 30 minutes. The results from these evaluations how a good correlation between the ChemScan system and the standard plate count method. This system will be successful application for not only in the field of pharmacology but also food microbiology. In addition, current identification of microbes by sophisticated instruments suitable for food microbiology, one of which Biology is manual system (BIOLOG\ulcorner), provides reference-level capability at a modes price. For the manual system, the color reactions in the microplate are read by eye and manually keyed into personal computer. Species identification appears on the computer screen within seconds, along with biotype patterns, a list of closely related species, and other useful statistics. In present this is useful application for microbial ecology and epidemiological survey. RiboPrinter system newly produced by DuPont is now focusing among microbiologists in the world, and is one of the biggest microbial characterization system using a DNA-based approach. The technology analyzer is bacterial culture for its genetic fingerprint or riboprint pattern. Finally Bio-cellTracer system for automatic measurement of fungal growth and Fukitori-Maseter, a Surface Hygiene Monitoring Kit by using swabe procedure in food processing environment are briefly illustrated in this presentation.

• Journal of IKEEE
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• v.23 no.3
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• pp.947-953
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• 2019

The purpose of this paper is to explore an ASIC design for estimating sizes and concentrations of airborne micro-particles by the means of integrating, amplifying and digitizing electric charge signals generated by photo-sensors as it receives scattered photons by the presence of micro-particles, consisting of a pre-amplifier that detects and amplifies voltage or current signal from photo-sensor that generates charges (hole-electron pairs) when exposed to visible rays, infrared rays, ultraviolet rays, etc. according to the intensity of rays; a shaper for shaping the amplified signal to a semi-gaussian waveform; two discriminators and binary counters for outputting digital signals by comparing the magnitude of the shaped signal with an arbitrary reference voltages. The ASIC with the proposed architecture and functional blocks in this study was designed with a 0.18um standard CMOS technology from Global Foundries and the operation and performances of the ASIC has been verified by the silicons fabricated by using the process.

• Journal of Korean Medical classics
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• v.32 no.2
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• pp.33-47
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• 2019

Objectives : To review the meaning of Open-Close-Pivot and its transition over time. Methods : Annotations and explanations in chapters where the theory of Open-Close-Pivot originated from in the "Suwen(素問)" and "Lingshu(靈樞)" were examined, followed by philological examination of key physicians. Results & Conclusions : Yang Shang Shan(楊上善) compared the 'Open-Close-Pivot' to a door. Wang Bing(王冰) explained it's movement and stillness to be the principle behind the Three-Yin-Three-Yang's threefold division. Wang Ji(汪機), in "XuSuwenChao(續素問鈔)" explained its physiological function as the entering and exiting of Ying Wei(營衛), and its scope to be exterior, interior, and center. Ma Shi(馬蒔) stratified it similar to "Shanghanlun(傷寒論)"'s six stages, while Wu Kun(吳崑) categorized Shaoyang(少陽) as being in-between exterior and interior. Zhang Jing Yue(張景岳) suggested a standard for the entering-exiting and exterior-interior-center concepts of the Open-Close-Pivot. Zhang Zhi Cong(張志聰) argued a theory of Open-Close-Pivot that emphasized the meaning of Three-Yin-Three-Yang, while Gao Shi Zong(高士宗) explained the relationship between Open, Close, Pivot and the functioning process. Shi Shou Tang(石壽棠) explained the physiology and pathology in the actions among Open-Close-Pivot with a focus on Pivot. Ke Qin(柯琴) applied Open-Close-Pivot to "Shanghanlun(傷寒論)" and used it as the basic principle to the Six Channel Ground Theory(六經地面說), also clinically applying it in the identification and treatment of the Six Channel patterns. Conclusions : Counting based word embedding methods seems to be more effective than.