• 전기의세계
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• v.23 no.4
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• pp.46-52
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• 1974

Generally, it has been regarded that there are two kinds of the effect of the electrodes, especially of the cathode in the gas discharge, (a) the effect caused by the difference of the cathode meterial and (b) the effect by the change of the cathode surface state even in the same meterials. Thus the two effects must be investigated independently to study the roles of the cathode in gas discharges. This paper measured sparking voltage in Rare gas (Ar, He) for the change of sparking voltage in repeating sparks and for the effect of (a) and (b) mentioned above, under the condition that the desorption of impurities from the cathod can be nigligible, and it is obtained that the correlative relations of the work function, sparking voltage and secondary coefficient are comparatively simple. In addition, the interesting character of the minimum point of the paschen's curves is found. The results were as follows; 1) The value of (pd)min with minimum pint of sparking voltage, (Vs)min, is 0.7-0.9 Torr. cm in Argon, but is 5.6-7.1 Torr. cm in Helium, and Paschen's curve in Helium shows slow curve than in Argon. 2) The minimum point of the Paschen's curve is satisfied actually Townsend's self sustaining criterion in Argon, but non-satisfaction in Helium, and the Townsend's secondary coefficient .gamma. action have compound property (.gamma.$_{i}$, .gamma.$_{p}$, .gamma.$_{m}$) in Helium. 3) The dependenting character of work function in Helium is less than in Argon. 4) The minimum point of sparking voltage increase under oxidized electrode than clear electrode in Au and Ag, but minimum point decrease in Ni and Cu.

• The Journal of Pediatrics of Korean Medicine
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• v.22 no.2
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• pp.19-35
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• 2008

Objectives : As obese children have been increased, the interest in the impact of obesity on growth also have been increased. This study is to examine relations between obesity and skeletal maturity by analyzing body compositions and bone age. Methods : Subjects were composed of 233 children from 6 years to 17 years of age, without any other diseases related to growth, who visited the department of pediatrics, OO oriental medicine hospital and measured their body composition (body mass index, body fat ratio, fitness score) and bone age. Results : 1. As body mass index was increased, the skeletal maturity significantly was also increased. 2. As the mean of bone maturity was increased, the BMI was increased from the underweight type to the normal type to the overweight type; the bone maturity was increased as the fat ratio was increased from the normal type to the obese type to the excessively obese type; and the bone maturity was higher in the weak, obese type than the normal type when classified according to the Fitness Score. 3. The bone maturity of the overweight group in the BMI classification and excessively obese group in the fat ratio classification significantly were increased. 4. Skeletal maturity significantly was increased in children who developed secondary sexual character. 5. The significance of obesity causing increase of the skeletal maturity was higher in boys than in girls. 6. Only in the case of children without development of secondary sexual character, obesity caused an significant increases in the skeletal maturity. Conclusions : Obesity could cause the increase of skeletal maturity, and the obesity could affect more to the boys than girls and more to the children than teenagers.

• Hwankyungkyoyuk
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• v.11 no.2
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• pp.69-82
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• 1998

This study was performed to investigate the trends in Environmental Education Research of Korea. In this study, the papers in $\ulcorner$Hwankyungkyoyuk$\lrcorner$ (Journal of the Korean Society for Environmental Education) and $\ulcorner$Journal of the Korean Association for Research in Science Education$\lrcorner$ from the initial number to the latest number were investigated. The category of analysis in this study were the number of papers, research area, method, character, the major targets of Environmental Education, the major targets of research, the purpose of Environmental Education, and the contents of environment. The results of this study are as follows: 1. The number of papers in $\ulcorner$Hwankyungkyoyuk$\lrcorner$ were 178 and in $\ulcorner$Journal of the Korean Association for Research in Science Education$\lrcorner$ were 406(10 of them were related in environmental education) 2. The research areas of the papers were Environmental Education(52.4%), Social Environmental Education(19%), Environmental Science(8.5%), Science Education(7.9%), and Social Education(3.2%). 3. The major parts of the method of the papers were literature review(31.7%), survey research(21.2%), and descriptive study(20.3%). 4. More than half of the character of the papers were research on the actual condition(35.4%) and consciousness (17.9%), 5. The major targets of Environmental Education of the papers were secondary school students(33.9%) and elementary school students(18.8%). 6. The major targets of researches of the papers were secondary school students(33.8%), teachers(30.0％), the general public(20.0％), and elementary school students(18.8%). 7. The purpose of Environmental Education of the papers were Values and Attitudes(31.2%), Behaviors and Participations(29.6%), Knowledges and Informations(27.2%), and Skills(12%). 8. The contents of Environment of the papers were waste(27.7%), water quality(15.2%), the whole environment(12.5%), air quality(9.8%), natural environment(5.4%), soil(4.4%), energy(4.4%), and so on. The results indicated that the Environmental Education research of Korea were needed to be reinforced in the field of qualitative research method, teaching and learning strategy, the development of learninyg meterals, and teacher education.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.2
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• pp.155-160
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• 2020

Objectives : This study investigate to identify the stability of temperament and personality characteristics of patients including Posttraumatic Stress Disorder (PTSD) patients. Methods : The number of subjects was 102, of which 33 were PTSD patients and 69 were non-PTSD patients. To demonstrate the change in individual temperament and personality characteristics, Temperament and Character Inventory (TCI) were administered repeatedly on the subjects. Repeated measures ANOVA and simple main effects analysis were conducted. Results : When analysed by dividing the subjects into PTSD groups and non-PTSD groups, the differences between the primary and secondary tests did not appear in the non-PTSD groups, but the differences between the primary and secondary tests were significant in Harm Avoidance (HA), Reward Dependence (RD), Self-Directedness (SD), Cooperativeness (C). In addition, it was noted that the time and group interaction effects of HA, RD, SD and C were significant, and that the main effects of time of HA, RD, SD and C were significant. Conclusions : This study is meaningful in that in the course of experience and recovery of traumatic events, we have clinically confirmed that changes in the temperament, known as stable variables, are possible.

• Journal of Microbiology
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• v.43 no.6
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• pp.475-486
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• 2005

Fungal secondary metabolites constitute a wide variety of compounds which either playa vital role in agricultural, pharmaceutical and industrial contexts, or have devastating effects on agriculture, animal and human affairs by virtue of their toxigenicity. Owing to their beneficial and deleterious characteristics, these complex compounds and the genes responsible for their synthesis have been the subjects of extensive investigation by microbiologists and pharmacologists. A majority of the fungal secondary metabolic genes are classified as type I polyketide synthases (PKS) which are often clustered with other secondary metabolism related genes. In this review we discuss on the significance of our recent discovery of chalcone synthase (CHS) genes belonging to the type III PKS superfamily in an industrially important fungus, Aspergillus oryzae. CHS genes are known to playa vital role in the biosynthesis of flavonoids in plants. A comparative genome analyses revealed the unique character of A. oryzae with four CHS-like genes (csyA, csyB, csyC and csyD) amongst other Aspergilli (Aspergillus nidulans and Aspergillus fumigatus) which contained none of the CHS-like genes. Some other fungi such as Neurospora crassa, Fusarium graminearum, Magnaporthe grisea, Podospora anserina and Phanerochaete chrysosporium also contained putative type III PKSs, with a phylogenic distinction from bacteria and plants. The enzymatically active nature of these newly discovered homologues is expected owing to the conservation in the catalytic residues across the different species of plants and fungi, and also by the fact that a majority of these genes (csyA, csyB and csyD) were expressed in A. oryzae. While this finding brings filamentous fungi closer to plants and bacteria which until recently were the only ones considered to possess the type III PKSs, the presence of putative genes encoding other principal enzymes involved in the phenylpropanoid and flavonoid biosynthesis (viz., phenylalanine ammonia-lyase, cinnamic acid hydroxylase and p-coumarate CoA ligase) in the A. oryzae genome undoubtedly prove the extent of its metabolic diversity. Since many of these genes have not been identified earlier, knowledge on their corresponding products or activities remain undeciphered. In future, it is anticipated that these enzymes may be reasonable targets for metabolic engineering in fungi to produce agriculturally and nutritionally important metabolites.

• Macromolecular Research
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• v.14 no.1
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• pp.52-58
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• 2006

A novel fabrication of the patterned surfaces in the polymer films was demonstrated by using the self-organizing character of the block copolymers of polystyrene-b-oligothiophenes and polystyrene-b-aromatic amide dendron. Hexagonally arranged open pores with a micrometer-size were spontaneously formed by casting the polymer solutions under a moist air flow. The amphiphilic character of the block copolymers played the crucial role as a surfactant to stabilize the inverse emulsion of water in the organic solvent, and subsequently the aggregated structure of the hydrophilic oligothiophene or aromatic amide dendron segments remained on the interiors of the micropores. The chemical composition on the top of the surface of the microporous films was characterized by energy-filtering transmission electron microscopy (EFTEM) or a time-of-flight secondary ion mass spectrometer (ToF-SIMS). The characterizations clearly indicated that the patterned surfaces in the self-organized block copolymer films with the hexagonally ordered microporous structures were fabricated in a single step.

• Journal of Gifted/Talented Education
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• v.24 no.4
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• pp.483-507
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• 2014

This is a follow up study to develop an education model focused on creativity and character for gifted students in science. The purpose of this study was to explore the effective utilization of the model that was developed by conducting literature review, exploring the direction of science-gifted education through an in-depth interview, and studying science-gifted educational methods by using a Delphi survey. The developed science-gifted education model, termed the Blossom Model, consists of four educational dimensions: leadership, science inquiry, convergence, and problem solving. The education programs using the Blossom Model were developed with four secondary school teachers, and were applied to unit schools' gifted education classes or district education office's gifted education center. After class, the in-depth interviews were conducted with teachers individually, and students' outcomes were collected. So the effective utilization of the model was suggested by analyzing these results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.10
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• pp.1991-2000
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• 1994

In this paper, an alagorithm with six types of classification is suggested for the recognition system of hand-written Korean characters. After thinning process and truncating process for noise redection. The input images are used generalized by $64\times64$ size. The six type classification is composed of preliminary and secondary classification process by using the learning algoritm of multi-layer perceptron. Subblock Hough transform is used as local feature and sampling Hough transform is used as global feature. Experiment is conducted for 1800 characters which is written 31 times per each type by 10 persons. The 90% recognition rate is resulted by the preliminary classification of detection the final consonant and by the secondary classification of detecting the vowels.

• ALGAE
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• v.28 no.4
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• pp.307-330
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• 2013

The genus Cryptomonas is easily recognized by having two flagella, green brownish color, and a swaying behavior. They have relatively simple morphology, and limited diagnostic characters, which present a major difficulty in differentiating between species of the genus. To understand species delineation and phylogenetic relationships among Cryptomonas species, the nuclear-encoded internal transcribed spacer 2 (ITS2), partial large subunit (LSU) and small subunit ribosomal DNA (rDNA), and chloroplast-encoded psbA and LSU rDNA sequences were determined and used for phylogenetic analyses, using Bayesian and maximum likelihood methods. In addition, nuclear-encoded ITS2 sequences were predicted to secondary structures, and were used to determine nine species and four unidentified species from 47 strains. Sequences of helix I, II, and IIIb in ITS2 secondary structure were very useful for the identification of Cryptomonas species. However, the helix IV was the most variable region across species in alignment. The phylogenetic tree showed that fourteen species were monophyletic. However, some strains of C. obovata had chloroplasts with pyrenoid while others were without pyrenoid, which used as a key character in few species. Therefore, classification systems depending solely on morphological characters are inadequate, and require the use of molecular data.

• ALGAE
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• v.39 no.2
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• pp.59-74
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• 2024

Terrestrial cyanobacteria are extremely diverse. In urban areas, they can be found as black stains on the surface of building walls, stone monuments, or man-made structures. Many of the terrestrial cyanobacteria are still understudied. To expand knowledge of terrestrial cyanobacterial diversity, a polyphasic characterization was performed to identify 12 strains isolated from campus of University of the Ryukyus, Okinawa, Japan. Multigene phylogenetic analyses based on 16S rRNA gene and 16S-23S rRNA internal transcribed spacer (ITS) region showed that the isolated strains formed two independent subclades within Nodosilinea, and were distantly related to all described Nodosilinea species. The 16S-23S rRNA ITS secondary structures showed variations for D1-D1' and Box B domain, while V3 domain was almost identical among entire species of Nodosilinea, including the studied strains. In addition, a unique morphological character, i.e. forming nodule or spiral shape, was also observed in certain studied strains. According to polyphasic characterization, Nodosilinea coculeatus sp. nov. and Nodosilinea terrestrialis sp. nov., were proposed as two new species of terrestrial cyanobacteria from Okinawa.