• Journal of The Korean Association For Science Education
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• v.22 no.1
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• pp.110-121
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• 2002

In this study, the verbal interactions occurred during the CASE(Cognitive Acceleration through Science Education) activities in the middle school science class has been analyzed regarding with students cognitive level. The subjects were 24 students of 6 groups in a middle school in Korea. Verbal interactions within group discussions during CASE activities were audio-taped, transcribed, and analyzed. Also, classroom observation and interview with students were carried out. The results showed that the student with higher cognitive level tended to be a group leader. They had strong influences on the group discussions in each step of problem solving. Also, the higher cognitive level students were more active in metacognitive discussion and more often used scientific terms. When their group met difficulties in each stage of problem solving, such as perception of problem and designing experiment, the higher cognitive level students suggested some ideas to help their peers and gave them an explanation of how they worked. Low cognitive level students had difficulties in perception and solving the problem as compared with high cognitive students. It was common during activities for the low cognitive level students to fail to identify variables and to distinguish between dependent variables and independent variables. They failed to hold a number of variables at once. However, the metacognitive questions from their peers or teacher were helpful for them to construct the concept of controlling variables. If there is no student who has a high level of thinking in a group, it was necessary to intervene for teacher. A well judged questions from teacher created the cognitive conflict which causes the students to reconstruct their strategy for problem solving and reinforce the control of variables reasoning pattern. From the above results, it is concluded that students' cognitive levels are much related to the verbal interaction patterns. This suggests that teacher should consider individual student's cognitive level in organizing groups and intervene to facilitate the environment for metacognitive interaction.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.1
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• pp.37-44
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• 2013

Sodium hypochlorite and ethylene diamine tetra acetic acid are substances usually used during endodontic treatment. Several studies found that the bonding was negated with certain irrigants and some of the used irrigants have demineralizing and chealating effects, so it was advocated to omit the etching step in etch and rinse adhesive systems. The purpose of this in vitro study was to evaluate the influence of NaOCl & EDTA on the bonding strength of ethanol wet bonding. Thirty human molars were selected and mesiodistally sectioned into halves, thus providing sixty specimens. The specimens were randomly assigned to 4 groups(n=15) according to the irrigant regimen used : (1) irrigated with distilled water for 10min (control); (2) irrigated with 5.25% NaOCl(10min), flushed with 5.25% NaOCl(1min) (3) irrigated with 5.25% NaOCl, flushed with 17% EDTA (4) irrigated with 5.25% NaOCl, flushed with 17% EDTA. Each group was acid-etched with 37% phosphoric acid(except group 4) and had their dentin surfaces dehydrated with ethanol solutions : 50%, 70%, 80%, 95%, 3x100%, 30s for each application. After dehydration, a primer( 50% all bond 3 resin + 50% ethanol) was used, followed by the adhesive(ALL-BOND 3 RESIN) application. Resin composite build-ups were then prepared using an incremental technique. Specimens were sectioned into beams and submitted to a tensile load using a Micro Tensile Tester(Bisco Inc.). The data were statistically analyzed using one-way ANOVA and Tukey HSD at p<0.5 level. There was no significant difference on G1(control) and G2(irrigated with NaOCl only ). (p>0.05). G3(flushed with EDTA) showed significantly high tensile bonding strength compared to the G2 (p<0.05). G4( treated with EDTA but no acid-etching) was significantly lower value than G3. (p<0.05) Although there was no significant difference, 5.25% NaOCl seemed to have an adverse effect on the bonding strength of ethanol wet bonding. The flushing with EDTA after NaOCl irrigation prevents the decrease of bonding strength. The use of 17% EDTA as a final flush can enhance the bonding strength but EDTA flushing can't substitute for a acid-etching.

• Tuberculosis and Respiratory Diseases
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• v.43 no.4
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• pp.579-589
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• 1996

Background : Activation of neutrophil is critical for the clearance of microorganisms and toxic host mediators during sepsis. Unfortunately the activated neutrophil and its toxic byproducts can produce tissue injury and organ dysfunction. The leucocyte CD11/18 adhesion complex regulates neutrophil-endothelial cell adhesion, the first step in neutrophil migration to sites of injection and inflammation. To investigate the potential of neutrophil inhibition as a treatment strategy for sepsis, we evaluated the effects of monoclonal antibody against CD11b (MAb 1B6) in rats intrabronchial challenged with Escherichia coli. Methods : Animals were randomly assigned to receive monoclonal antibody against CD11b (1 mg/kg, sc) and bovine serum albumin(BSA, 1 mg/kg, sc) 6 hr before, at 0 and 6 hr after intrabronchial challenge of $20x10^9$ CFU/kg E. coli 0111. Animals were randomized to treat either 24, 60 or 90% oxygen after bacterial challenge and begining 4 hr after inoculation, all animals were received 100 mg/kg ceftriaxone qd for 3 days. Peripheral and alveolar neutrophil(by bronchoalveolar lavage) counts and lung injury parameters such as alveolar-arte rial $PO_2$ difference, wet to dry lung weight ratio and protein concentration of alveolar fluid were measured in survived rats at 12 hr and 96 hr. Results : Monoclonal antibody against CD11b decreased circulating and alveolar neutrophil especially more in 12 hr than in 96 hr The lung injury parameters of antibody-treated animals were not different from those of BSA-treated animals. but It was meaningless due to small number of survived animals. The early(6 hr) mortality rate was significantly increased in antibody-treated group(51%) compared to BSA-treated group(31%) (P=0.02) but late(from 12 hr to 72 hr) mortality rate was not different in antibody-treated group(44%) from BSA-treated group(36%) (P =0.089). Conclusion : Leucocyte CD11b/18 adhesion molecule is known to regulate neutrophil migration to the site of infection and inflammation. The monoclonal antibody against CD11b decreased alveolar neutrophil in rats with pulmonary sepsis and increased early mortality rate. Therefore, we can speculate that monoclonal antibody against CD11b blocks of alveolar recruitment of neutrophils, impairs host defense mechanism and increases early mortality rate of pulmonary sepsis in rat.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.331-336
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• 2012

This study was carried out to evaluate the wheat cultivation system to reduce costs and mechanize wheat production. A field study was conducted for 2 years (2009 to 2010) at the National institute of crop science, Iksan, Korea. We used working system I and working system II for the experiment. Working system I is used a multiple machine attached with a spreader tractor (seeding, fertilization, seed coverage, and weed control functionality) and working system II is used a multiple machine with a tractor which works for simultaneous job when seeding step (seeding, fertilization, and seed coverage). Sowing to harvesting operation time is 118 hours/ha for mechanize with conventional planting. Working system I is a multiple machine and a combine machine with a tractor, which worked 26 hours/ha lower than conventional planting. Working system II is 18 hours/ha lower than conventional planting. The reduced work efforts of working system I and II were 78% and 85% respectively. The growth and yield of wheat according to working system I and II is lower than conventional planting. Therefore, a multiple machine needs to study for appropriate seeding rate. Mechanization cost in consideration of the mechanical break-even point when the working system I is 3.7 ha and working system II is 4.2 ha. The farm income is enhanced by working system I (778,110 won/ha) and working system II (849,930 won/ha). The results showed that application of a multiple machine lowered costs of wheat production.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.3-7
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• 2012

Purpose : In myocardial perfusion SPECT, the type of orbit (circular vs. body contouring) that affect the image quality is still on the debate. Presently in the nuclear medicine field, the body contouring orbit acquisition is widely used to improve the image quality on the myocardial perfusion SPECT. But in case of body contouring acquisition using the vertical method with dual detect machine, there is a tendency of increasing the radius. In this research, we compared body contouring orbit acquisition with circular orbit acquisition, so we suggest ideal method that reduces the radius for improving image quality. Materials and Methods : Phantom and clinical studies were performed. The anthropomorphic torso phantom was made on equally with counts from patient's body. The study was performed under six different conditions. To compare image quality according to the radius, we increased radius sequentially per step during circular orbit acquisition. On the other hand, sensors that protect a collision and reduce the radius automatically were used to acquire image during body contouring orbit acquisition. So we compared FWHM value of apex. In clinical studies, we analyzed the 40 patients who were examined by Tl-201 gated myocardial perfusion SPECT in department of nuclear medicine at Asan Medical Center in August 2011. To acknowledge the differences according to the radius, we acquired the results two times using circular orbit acquisition and body contouring orbit acquisition. Results : In phantom study, we analyzed that increase of radius resulted in changes of FWHM value. It was 5.41, 6.24, 6.33, 6.42, 6.93 mm. On the other hand, using the body contouring orbit acquisition, FWHM value was 6.23 mm. In clinical study, difference of average radius between two methods was 2.5 cm (circular orbit acquisition was more close to patients). Conclusion : Through the experiments using Anthropomorphic torso phantom and patients data, we found that FWHM value of circular orbit acquisition was lower than body contouring orbit acquisition. As a result, if the difference of average radius exists approximately 3 cm, circular orbit type acquisition is better than body contouring type acquisition. But clinical investigation is only aimed to average radius, so it needs more investigation in comparison of patient's image.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.1-23
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• 2014

Market forecasting aims to estimate the sales volume of a product or service that is sold to consumers for a specific selling period. From the perspective of the enterprise, accurate market forecasting assists in determining the timing of new product introduction, product design, and establishing production plans and marketing strategies that enable a more efficient decision-making process. Moreover, accurate market forecasting enables governments to efficiently establish a national budget organization. This study aims to generate a market growth curve for ICT (information and communication technology) goods using past time series data; categorize products showing similar growth patterns; understand markets in the industry; and forecast the future outlook of such products. This study suggests the useful and meaningful process (or methodology) to identify the market growth pattern with quantitative growth model and data mining algorithm. The study employs the following methodology. At the first stage, past time series data are collected based on the target products or services of categorized industry. The data, such as the volume of sales and domestic consumption for a specific product or service, are collected from the relevant government ministry, the National Statistical Office, and other relevant government organizations. For collected data that may not be analyzed due to the lack of past data and the alteration of code names, data pre-processing work should be performed. At the second stage of this process, an optimal model for market forecasting should be selected. This model can be varied on the basis of the characteristics of each categorized industry. As this study is focused on the ICT industry, which has more frequent new technology appearances resulting in changes of the market structure, Logistic model, Gompertz model, and Bass model are selected. A hybrid model that combines different models can also be considered. The hybrid model considered for use in this study analyzes the size of the market potential through the Logistic and Gompertz models, and then the figures are used for the Bass model. The third stage of this process is to evaluate which model most accurately explains the data. In order to do this, the parameter should be estimated on the basis of the collected past time series data to generate the models' predictive value and calculate the root-mean squared error (RMSE). The model that shows the lowest average RMSE value for every product type is considered as the best model. At the fourth stage of this process, based on the estimated parameter value generated by the best model, a market growth pattern map is constructed with self-organizing map algorithm. A self-organizing map is learning with market pattern parameters for all products or services as input data, and the products or services are organized into an $N{\times}N$ map. The number of clusters increase from 2 to M, depending on the characteristics of the nodes on the map. The clusters are divided into zones, and the clusters with the ability to provide the most meaningful explanation are selected. Based on the final selection of clusters, the boundaries between the nodes are selected and, ultimately, the market growth pattern map is completed. The last step is to determine the final characteristics of the clusters as well as the market growth curve. The average of the market growth pattern parameters in the clusters is taken to be a representative figure. Using this figure, a growth curve is drawn for each cluster, and their characteristics are analyzed. Also, taking into consideration the product types in each cluster, their characteristics can be qualitatively generated. We expect that the process and system that this paper suggests can be used as a tool for forecasting demand in the ICT and other industries.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.215-224
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• 2009

A review was given of the role of traditional morphometrics in plant morphological studies using 54 published studies in three major journals and others in Korea, such as Journal of Korean Forestry Society, Korean Journal of Plant Taxonomy, Korean Journal of Breeding, Korean Journal of Apiculture, Journal of Life Science, and Korean Journal of Plant Resources from 1997 to 2008. The two most commonly used techniques of data analysis, cluster analysis (CA) and principal components analysis (PCA) with other statistical tests were discussed. The common problem of PCA is the underlying assumptions of methods, like random sampling and multivariate normal distribution of data. The procedure was intended mainly for continuous data and was not efficient for data which were not well summarized by variances or covariances. Likewise CA was most appropriate for categorical rather than continuous data. Also, the CA produced clusters whether or not natural groupings existed, and the results depended on both the similarity measure chosen and the algorithm used for clustering. An additional problems of the PCA and the CA arised with both qualitative and quantitative data with a limited number of variables and/or too few numbers of samples. Some of these problems may be avoided if a certain number of variables (more than 20 at least) and sufficient samples (40-50 at least) are considered for morphometric analyses, but we do not think that the methods are all mighty tools for data analysts. Instead, we do believe that reasonable applications combined with focus on objectives and limitations of each procedure would be a step forward.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.284-290
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• 2013

This study analyzed the geometric, compressive, cutting and friction properties of oriental melons in order to design a gripper capable of soft handling and a cutter for cutting oriental melon vine among the end effector of oriental melon as a preliminary step for developing the end effector of the robot capable of harvesting oriental melons in protected cultivation. As a result, the average length, diameter at the midpoint, weight, volume and roundness of the oriental melons were 108 mm, 70 mm, 188 g, 333 mL and 3.8 mm. Nonlinear regression analysis was performed on the equation $W=L^a{\times}D_2^b$ with variation of the length (L) and diameter (D2) of the weight (W) of the oriental melons. As a result, it was shown that there was a correlation between a of 2.0279 and b of -0.9998 as a constant value. The average diameter of the oriental melon vine was 3.8 mm, and most vines were distributed within a radius of 5 mm from the center. The average yield value, compressive strength and hardness of the oriental melons were $36.5N/cm^2$, $185.7N/cm^2$ and $636.7N/cm^2$, respectively. The average cutting force and shear strength of the oriental melon vines were $2.87{\times}10^{-2}\;N$ and $5.60N/cm^2$, respectively. The maximum friction coefficient of the oriental melons was rubber of 0.609, followed by aluminium of 0.393, stainless steel of 0.177 and teflon of 0.079. It was considered possible to apply it to the size of the gripper and cutter, turning radius, dynamics of drive motor and selection of materials and their quality in light of the position error and safety factor according to the movement when designing end effector based on the analyzed data.

• 대한공업교육학회지
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• v.37 no.1
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• pp.145-164
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• 2012

The purpose of this study is to develope the teaching materials of career education for the 'Information and Communication Technology and Our Life' unit in the technology education. As preparation phase, in order to choose the suitable contents for career education, we analyzed the technology education curriculum and 'Information and Communication Technology and our Life' unit of technology and home economics. And then we compared and analyzed the existing related researches. After content analysis of the teaching materials for career education, we mapped the contents into career education area. In the 'Design' step of teaching, we extracted the unit design components after analyzing 'Development in Information and Communication Technology' unit of eleven text books used in 2007 revised curriculum In the 'Introduction', 'Activity', 'Arrangement' steps of teaching, by applying the SHIP model, one of career education program model, we develop the teaching materials. Then, we get expert evaluation using questionnaire and improve the suitability of the teaching materials. The results are as followings: First, our teaching materials reflect the development history of information and communication technology well, show the features of career education, and are suitable to middle school students as the teaching materials. Second, our teaching materials can help students to face various jobs related with the development of Information and communication technology, to have more interests and exploring opportunities about 'Information and Communication Technology' subject. Third, our teaching materials can help teachers to use it for the career education of 'Information and Communication Technology and our Life' unit of 2007 revised curriculum in the class time. Our teaching materials can also be used in the extra activity related to career education and the Creative Experience Activities. Furthermore, since 2009 revised curriculum includes the career education unit in the 'Information and Communication Technology' subject, our teaching materials can be used partially as the teaching materials in the future.

• Pediatric Infection and Vaccine
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• v.22 no.2
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• pp.63-68
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• 2015

Purpose: This study analyzed a small outbreak of measles at a single hospital located in northern Gyeonggi-do in 2013. Methods: We reviewed the medical records of measles patients at The Catholic University of Korea Uijeongbu St. Mary's Hospital from August to October, 2013. Results: Fifteen children were confirmed to have measles by RT-PCR and serum IgM test; 1 neonate, 11 infants, and 3 toddlers. None of the patients had received Measles-Mumps-Rubella vaccination. All patients showed B3 type in viral genotyping. Nine children (60%) had been exposed to measles during treatment for other diseases in the pediatric ward. Incubation period was between 8 and 15 days. Fever started at a median 10 days after exposure and persisted for a median of 8 days. Rash showed at a median 13 days after exposure. Respiratory complications were observed in 40% of patients. Diarrhea developed in 53% of patients. Conclusion: Although measles has been well-controlled due to the high rate of vaccination coverage, it is possible to have an outbreak at any given time, especially in infants. We must learn from this outbreak, and remain fully aware of the possibility of reemergence and provide proper management, including vaccination or immune globulin administration, to infants exposed to measles. Reevaluation of serum IgG titer of neonates, infants, and pregnant women may be the first step to prevent further outbreaks.