• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.370-376
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• 2001

In this study, high school students' problem-solving strategy-performing ability was measured by an essay-type test. The relationship between students' logical thinking ability and strategy-performing ability was also investigated. Four classes (N=187) were selected from two high schools in Seoul, and the strategy performance ability test and the Group Assessment of Logical Thinking (GALT) were administered. Evaluation scheme for strategy-performing ability consists of 7 subcategories - understanding given of problems, recalling related law, setting up subgoals, deriving physical quantities, logical progress, mathematical execution, and reviewing. The intercoder agreement for scaling was .92, which indicated substantial strength of agreement. The results revealed that students' ability of understanding given of problems and mathematical execution was relatively high. However, their ability of setting up subgoals and reviewing was very low. The total scores of the strategy performance ability test and all of the scores of each subcategory were significantly correlated with the GALT scores.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.6
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• pp.221-227
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• 2013

This paper proposes an improved steganalysis method based on image categorization. In general, most steganalysis methods extract the statistical moments based features which contain the global natures of images regardless of their inherent characteristics. However, the steganalysis method based on the statistical moments leads to degraded performance by applying to images with different complexity. In this paper, we decompose an 8-bit image into an upper 4-bit plane and a lower 4-bit plane, and categorize the image with two classes according to the correlation coefficient between decomposed sub-images. Two independent steganalyses can be performed for the categorized images. Since our method uses independent steganalysis technique according to the image category, it can reduce the drawback of the steganalysis methods utilizing the statistical moments. The performance of the proposed scheme is compared with well-known four steganalysis methods. Experiment results show that the proposed scheme has higher detection rate than previous methods.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.1
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• pp.17-24
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• 2006

Objectives: To analyze the general characteristics and clinical differences of poisoning in children and adolescents and to take precautions of occasions. Methods: We retrospectively evaluated poisoning children and adolescents (less than 19 years) visiting to the emergency medical center of tertiary hospital in urban area. We collected demographic data, substance exposure data (materials, causes of poisoning and amount), and clinical outcome of poisoning for the past 2 years and 9 months. Results: 189 cases were reported of concerning poisoning in children and adolescents. The age groups were divided into four categories. (1) Infants group:<2 year, (2) Preschool age group: $2{\sim}5year$, (3) Children group: $6{\sim}12year$ and (4) Adolescents group: $13{\sim}18year$. The most vulnerable age group was the infants group. There were two-peaks of age distribution in poisoned patients on the whole. Various types of materials belonged to classes of druqs (56.6%). household products (34.4%) and industrial solvents (9.0%). On adolescents group, the frequency of drug poisoning was significantly high, in comparison with infants, preschool age, and children group (p=0.001). Most of the patient groups had been poisoned accidentally(73.5%), while most cases of adolescents poisoning had been intentional. 63% of the adolescents group had a suicidal purpose. Conclusion: The incidence of poisoning was most highly due to drugs. The cause of poisoning is most commonly accidental. while in adolescent group, intentional poisoning is mostly common. Special cares, like keeping children away from drugs, will be needed to prevent children poisoning, and psychiatric consultation and supportive cares can reduce the adolescents poisoning cases.

• Archives of design research
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• v.15 no.2
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• pp.101-114
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• 2002

On the threshold of year 2000, the elderly account for more than 7% of the whole population in Korea, which means that the nation is greeting welcoming an aging society. Accordingly, it is expected that silver businesses and services targeted at the silver generation will prosper with "silver advertising design" becoming active. Under such circumstances, this study was aimed at reviewing the recent silver marketing advertisements in terms of their cultural and moral implications, and thereby, redefining and reestablishing the status of silver consumers to help them find their identity, aware of marketing activities and therewith, establish their "consumer sovereignty". This study consists in large of 5 chapters. The introduction parr describes background, purpose, method and scope of the study. The first chapter reviews the silver marketing theories. The second chapter classifies the silver marketing advertisement positioning of four style - upper classes style, effloresce progress style, self- sufficiency style, dependent style - and reviews the expression strategy of each positioning. The third chapter examines the domestic conditions of silver marketing advertisements for each positioning type classified. The fourth chapter designs the ′creative′of silver marketing advertisements and suggests the methods thereof. The analysis of ′creative′was tested in terms of graphic gestaltung, and how the sliver marketing advertisement positioning should be discerned depending on silver generation consumer′s characteristics was discussed. The fifth chapter puts forwards the suggestions for the ′creative′ strategies to enhance the effects of the silver marketing advertisements, based on the preceding discussions. In addition, the Perspective into the keyword of 21 st century or "silver design" is discussed, together with the limitations of this study. It is hoped that this stuffy will be conducive to our efforts to face the upcoming′age\ulcorner society′more effectively. To this end, this study discusses the "silver advertising design" in light of ′societal concepts′and ′customer-oriented value′, and thus, explores some creative presentation strategies whereby individual companies interests and social or public interests can be compromised through ′creative activities′ and ′equal-value consumerism′ for an ultimately effective management strategies for silver businesses and services.

• The Plant Pathology Journal
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• v.28 no.1
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• pp.20-31
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• 2012

Endophytic bacterial communities of tidal flat plants antagonistic to oomycete plant pathogens were studied by the isolation of 256 root colonizing endophytic bacteria from surface-disinfected root tissues of six plants ($Rosa$ $rugosa$, $Suaeda$ $maritima$, $Vitex$ $rotundifolia$, $Carex$ $scabrifolia$, $Glehnia$ $littoralis$ and $Elymus$ $mollis$) growing in a tidal flat area of Namhae Island, Korea. To understand the antagonistic potential, an $in$ $vitro$ antagonistic assay was performed to characterize and identify strains that were antagonistic to the oomycete plant pathogens $Phytophthora$ $capsici$ and $Pythium$ $ultimum$ from the total population. Nine percent of the total number of isolated bacteria exhibited in vitro inhibitory activity against target plant pathogenic oomycetes. Taxonomic and phylogenetic placement of the antagonistic bacteria was investigated by analysis of the 16S rRNA gene sequences. The sequence analysis classified the antagonistic strains into four major classes of the domain bacteria ($Firmicutes$, ${\alpha}-Proteobacteria$, ${\gamma}-Proteobacteria$ and $Actinomycetes$) and 10 different genera. Further production of secondary metabolites, hydrolytic enzymes and plant growth promoting traits were determined for the putative new species of antagonistic endophytic bacteria. These new strains could not be identified as known species of ${\alpha}-Proteobacteria$, and so may represent novel bacterial taxa. The unexpected high antagonistic bacterial diversity associated with the tidal flat plants may be indicative of their importance in tidal flat plants as a promising source of novel antimicrobial compounds and biocontrol agents.

• Food Science of Animal Resources
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• v.30 no.4
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• pp.626-633
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• 2010

This study examined the relationship between meat color and myoglobin content, and evaluated their influence on muscle fiber characteristics and overall pork quality. Four groups of pigs were classified by lightness (CIE $L^*$) and redness (CIE $a^*$): HH, high lightness and high redness; HL, high lightness and low redness; LH, low lightness and high redness; LL, low lightness and low redness. Myoglobin content ranged from 1.2 mg/g to 2.1 mg/g, and was highest in the LH group and lowest in the LL group (p<0.05). Myoglobin content correlated significantly with redness (CIE $a^*$) (r = 0.45, p<0.01). Fiber compositions of type I and IIA were closely related to lightness and redness. Pork with higher sizes of type IIA and IIB fibers had lower lightness and redness, respectively, which was tougher than the other pork. Pork having the highest lightness and lowest redness, often considered "pale", has higher values in drip loss than the other classes of pork tested.

• Journal of Korean Elementary Science Education
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• v.29 no.3
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• pp.262-276
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• 2010

The purpose of this study was to investigate and analyze the elementary teachers' views and students' views about the difficulties in teaching and learning on open inquiry activities of elementary school science. Semi-structured interviews were conducted individually with three elementary teachers who have serviced more than three years, and with twenty four elementary students attending schools located in Cheongju City. And their anecdotes were collected and analyzed. The interview questions were developed through Seidman's steps to acquire the reliability in the interview data. From the interviews and anecdotes, we found that elementary teachers' views about the difficulties of teaching open inquiry activities: the difficulties of teaching in finding inquiry problem and planning inquiry, the difficulties of managing group activities, the difficulties of managing class hours for inquiry, the lack of the students' inquiry abilities, and problems on students' affective characteristics. And the students have the views about the difficulties in doing open inquiry activities: the difficulties of finding inquiry problem and planning inquiry, being unaccustomed to write reports, the troubles with investigating, problems on affective characteristics, the difficulties of joining in a group, and the lack of inquiry abilities. The teachers give suggestions for effective application of the open inquiry activities: first, the teachers must encourage students' emotion and will in doing open inquiry activities, second, there must be the steady inquiry teaching and learning in ordinary elementary science classes. Based on the results, this study suggested that elementary teachers should concern specially about students' being unaccustomed to write reports and the troubles in doing scientific investigation.

• Journal of The Korean Association For Science Education
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• v.19 no.4
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• pp.635-644
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• 1999

The effect of cooperative learning in a heuristic approach (four stage-problem solving strategy) that also emphasized molecular level representation was studied. Three high school classes (N=130) were randomly assigned to St group (using strategy individually), St-Co group (using strategy in cooperative group), and control group. After instruction, students' multiple-choice problem solving ability, strategy performing ability, and the perception of involvement were compared. Students' preferred instruction type was also examined. Although multiple-choice problem solving ability were not different significantly, a significant interaction between the treatment and the previous achievement level was found in strategy performing ability. Analysis of simple effects indicated that the medium-level students in the St group performed better than those in the St-Co group. In the perception questionnaire of involvement. however, the scores of the St group were significantly lower than those of the control group. The instruction type that students most preferred was also St-Co.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.6
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• pp.367-373
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• 2007

We assessed the stock of the southern bluefin tuna (SBT, Thunnus maccoyii) by applying the MULTIFAN-CL model. The model is spatially disaggregated, with the population and fisheries stratified into a number of regions within the overall stock range. Catch, effort, length-frequency, and tagging data from 1965 to 2003 were stratified by three regions and four quarters (Jan-Mar, Apr-Jun, Jul-Sept and Oct-Dec). These data were used to estimate the instantaneous fishing mortality (F), biomass, spawning biomass, recruitment, and so on. The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) used only Japanese data and did not consider migration for the SBT stock assessment. By contrast, we used Japanese, Australian, New Zealand, Taiwanese, and Korean data, and considered migration. As a result, the estimated annual average F of all age classes was 0.073/yr and the F of age class 6-10 was the highest. The results also showed that the biomass and recruitment of SBT had declined significantly after 1965. Compared with the CCSBT results, the estimated spawning biomass in this study was lower and more uncertain. However, we will conduct a sensitivity analysis to get more accurate biological parameters and results. In addition, we need to use the bootstrap resampling method to quantify the uncertainty.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.5
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• pp.582-588
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• 2016

Seventy-nine Vibrio parahaemolyticus isolates from surface seawater from Gomso Bay, west coast of Korea, were analyzed for the presence of virulence genes and their susceptibility to 30 different antimicrobials. All 79 isolates were examined for the presence of two virulence genes (tdh or trh) using polymerase chain reaction (PCR); however, no isolates possessed either the tdh or trh gene. According to a disk diffusion susceptibility test, all of the strains studied were resistant to oxacillin, penicillin, and vancomycin, followed by ticarcillin (97.5%), ampicillin (96.2%), clindamycin (86.1%), erythromycin (10.1%), streptomycin (7.6%), cefoxitin (6.3%), amikacin (2.5%), and cephalothin (2.5%). However, all of the strains were susceptible to 19 other antimicrobials including cefepime, cefotaxime, chloramphenicol, gentamycin, nalidixic acid, sulfamethoxazole/trimethoprim, and trimethoprim. All 79 isolates (100%) were resistant to four or more classes of antimicrobials, and two strains exhibited resistance to eight antimicrobial agents. The average minimum inhibitory concentrations (MICs) for V. parahaemolyticus for ampicillin, penicillin, ticarcillin, and vacomycin were 946.5, 1,305.9, 1,032.3, and 45.0 µg/mL, respectively.