• Composites Research
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• v.32 no.6
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• pp.327-334
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• 2019

The delamination is a special mode of failure occurring in composite laminates. Several numerical studies with finite element analysis have been carried out on the delamination behavior of unidirectional composite laminates. On the other hand, the fracture for the multi-directional composite laminates may occur not only along the resin-fiber interface between plies known as interply or interlaminar fracture but also within a ply known as interyarn or intralaminar fracture accompanied by matrix cracking and fiber bridging. In addition, interlaminar and intralaminar cracks appear at irregular proportions and intralaminar cracks proceeded at arbitrary angle. The probabilistic analysis method for the prediction of crack growth behavior within a layer is more advantageous than the deterministic analysis method. In this paper, we analyze the crack path when the mode I load is applied to the cross-ply carbon/epoxy composite laminates and collect and analyze the probability data to be used as the basis of the probabilistic analysis in the future. Two criteria for the theoretical analysis of the crack growth direction were proposed by analyzing the stress field at the crack tip of orthotropic materials. Using the proposed method, the crack growth directions of the cross-ply carbon/epoxy laminates were analyzed qualitatively and quantitatively and compared with experimental results.

• Information Systems Review
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• v.16 no.1
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• pp.89-106
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• 2014

The war simulation systems in Republic of Korea Army have been getting more and more important because soldiers can effectively and efficiently learn and share their war-related knowledge based on the interactions through the systems. But, up to now, the access to the war simulation systems has been limited to only soldiers. So, little research on them has been conducted. This study explores the effects of the antecedents to the flow experience and the characteristics of the systems on soldiers' intentions to use them. Based on the 118 samples collected from officers in Republic of Korea Army, this study empirically shows the logical reality of the war simulation systems and the flow experience positively influence soldiers' intentions to use the systems and the clarified goals, feedbacks, and the levels of the missions in the systems are significant antecedents to the flow experience. Useful implications are presented and discussed based on the new findings.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.620-625
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• 1993

This experiment was carried out to predict the sensory properties of yogurt by instrumental methodology. Sensory attributes such as viscosity, mouth-feel, taste and quality were investigated. Instrumental parameters were measured with refractometer, viscometer, consistometer and rheometer. Sensory data showed that viscosity of peach yogurt was higher than that of strawberry and tropical-fruit-mixed (TFM) yogurts (p<.05). All instrumental parameters of peach yogurt were higher than those of strawberry and TFM yogurts, except cohesiveness and elasticity (p<.05). Viscosity measured by panelists was significantly correlated with instrumental viscosity, consistency, hardness, adhesiveness and gumminess in the fruit yogurts (p<.05). But mouth-feel and quality of yogurts showed poor relationships with instrumental parameters. The effective instrumental parameters for predicting sensory viscosity ($Y_{1}$) of yogurts were consistency ($X_{1}$), viscosity ($X_{2}$) and cohesiveness ($X_{3}$). And those for predicting mouth-feel ($Y_{2}$) were consistency. The estimated regression equations were as follows; $Y_{1}=4.968-0.0486X_{1}+0.00012X_{2}+0.0348X_{3},\;Y_{2}=5.701+0.0154X_{1}$.

• Journal of Forest and Environmental Science
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• v.15 no.1
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• pp.98-106
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• 1999

This study was carried out to analyze the mechanical properties of soil for counterplan of recovery construction and the slope stability on fill slope of Sang-gul forest road in Mt. Gari. To analyze the mechanical properties of apparent soil on fill slope in forest road, various soils such as soil, gravelly sandy soil, weathered rock were used as experimental sample in this study. In each experimental sample, particle size distribution test, liquid limit test, plastic limit test, and specific gravity test were carried by Korean industrial standards(KS F 2302, KS F 2303, KS F 2304, KS F 2306, KS F 2308). Through the results of soil particle size distribution analysis, soil moisture content analysis, and specific gravity analysis, soil texture, uniformity coefficient, curvature coefficient, dry density and specific gravity were able to be determined in sampling site. As a results in this study, soil was classified as SP, SW, GP by Unified Soil Classification Standard (USCS). specific gravity and dry unit weight of soil have the value range of 2.52~2.60 and 1.39~1.43, respectively. Also plastic index showed non plastic condition.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.365-397
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• 2020

To investigate the distribution of vascular plants growing at Apsan park, we surveyed from April in 2018 to October in 2019. The flora of Apsan park was classified as a total of 721 taxa comprising of 114 families, 382 genus, 619 species, 5 subspecies, 77 varieties, 12 forma, 5 hybrid, 3 cultivation. Among them, The Rare plants species 23 taxa, endemic plants 15 taxa, floristic regional indicator plants 98 taxa, naturalized plants 57 taxa were recorded. The percentage of urbanization index was 17.76%, the naturalized ratio was 7.91%, respectively.

• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.262-270
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• 2011

Track support stiffness which affected track maintenance and riding comfort had a big effect on the track and train. Also, track support stiffness of the track design which was based on theory differs from track support stiffness of the track generated on the field. Track support stiffness was generated by several factors such as dynamic wheel loads, vertical displacement of track, and stress at rail bottom on the field test. With the results of the field test was compared with theoretical value. This paper analyzed that track support stiffness of ballast depended on condition of ballast, and support stiffness of concrete track also depended on the characteristic of track structures such as, normal elastic fastening system, rail floating system and sleeper floating system. However, on the ballast and concrete track, the designed track support stiffness was underestimated less than the measured track support stiffness. When the track condition was estimated on service line, it would not consider the track condition on the field. Therefore, this study proposed the various track type and the range of track support stiffness based on the experimental test.

• Tuberculosis and Respiratory Diseases
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• v.57 no.6
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• pp.604-608
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• 2004

A 47-year-old-man was admitted to the emergency department with dyspnea, right pleuritic pain, and high fevers for 3 days. He had a nonproductive cough that exacerbated the chest pain. A clinical examination revealed distressed and slightly tachypneic patient, with blood pressure of 110/90 mmHg, temperature of $39^{\circ}C$, pulse of 90 beats/min, respiratory rate of 24 breaths/min. A chest examination showed significantly diminished breath sounds in the right lung with dullness to percussion. Laboratory investigation demonstrated leukocytosis and a raised C-reactive protein. The results of arterial blood gas analysis revealed moderate hypoxemia. A radiograph and a CT scan of the chest showed extensive consolidation with multifocal low densities, and pleural effusion in the right lung. A diagnostic thoracentesis revealed straw-colored fluid, which was found to be a neutrophil-predominant exudate. At 7 days after admission, the clinical symptoms had not improved and the temperature was still $39^{\circ}C$ despite the aggressive therapy of community-acquired pneumonia. After comprehensive history taking, we realized then that he accidentally aspirated kerosene while siphoning from fuel tank to put into the boiler 3 days ago. Bronchoscopy with bronchial washings could be successful in establishing the diagnosis of hydrocarbon pneumonitis by demonstration of a high lipid-laden macrophage index. Thereafter, the symptoms and radiographic opacities gradually improved, and he was discharged several days later.

• Journal of the Korean Geographical Society
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• v.43 no.4
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• pp.655-679
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• 2008

This study is to analyze the base of selection and feature of description on Korea-related content in Japanese curriculum(geography and history) and high-school geography textbooks. Japanese curriculum requires that there are two or three neighbor countries to be selected and their contents consist of life and culture and have to compare with those of japan in view of understanding and respect on similarity and difference. The content of physical environment is only dealt as factors influencing on life and culture because regional teaming of neighbor countries focus on it. Dok-do is described with conflict region in most of textbooks. But some textbooks describe Dok-do with territory of Shimane-Hyun in Japan or devide like japanese territory on the map. There are described han-gul(Korean language), confucianism, buddhism and christianity, han-bok(Korean clothes), rice and soup, bulgogi(Korean meat dishes) and scissors, spoon and chopsticks, ondol(Korean floor heater), etc. with the cases of specific Korean life and culture. And, exchange between Korea and Japan focuses on more cultural view increasing recently than political and economical view. Then Japanese high-school geography textbooks humanize geography because of they focus on life and culture and promote not only knowledge and understanding but also altruism and empathy because they focus on similarity and difference through comparison between neighbor country and Japan. This shows how to able to practice regional teaming in globalization and multicultural society.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.4
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• pp.568-574
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• 2009

Tongue-tie is a congenital anomaly characterized by an abnormally short lingual frenum, which may restrict tongue tip mobility, In the neonate and infant, tongue-tie was said to cause difficult breast-feeding, In the older infant, toddler and young child, poor speech has been frequently listed because movement of tongue tip is limit ed. Also as a abnormal tongue position, various orthodontic problems, later mechanical and social manifestations could be developed. Treatment options such as observation, speech therapy, frenotomy and frenectomy have been suggested. The optimal timing for the surgery has not been determined, but early intervention may be appropriate for the children with significant tongue-tie who has the significant potential to speech difficulties and later social and mechanical problems. Sedation is an effective method for incapable of cooperative and the handicapped children, necessary to early intervention. We report three cases, using oral sedation for the frenectomy in young children with severe tongue-tie. After treatments, we could find out sufficient tongue movement and improved speech ability.

• Sleep Medicine and Psychophysiology
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• v.18 no.1
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• pp.35-39
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• 2011

Objective: Diurnal preference is an attribute reflecting whether people are alert and preferring to be active either early or late in the day. It also referred to as chronotype or morningness-eveningness trait. The PER3 genes have been known to influence diurnal preference. In this study, we have investigated the associations between the PER3 gene polymorphisms and diurnal preference in a healthy young population, controlling for the social and environmental confounding factors. Methods: The participants in this experiment included 299 unrelated medical college students (M=191, F=108), with a mean age of 22.9 years. Diurnal preference was measured by a single administration of the 13-item Composite Scale for Morningness (CSM). Genotyping of the PER3 VNTR (rs57875989) was performed using polymerase chain reaction. A two-tailed alpha of 0.05 was chosen. Results: The mean${\pm}$SD score on the CSM scale for all subjects was 31.90${\pm}$6.39. There was no significant difference in total CSM score between gender groups, although females showed a trend towards higher morningness score. Although PER3 5R/5R showed the tendency towards high CSM scores, there were no significant differences on CSM scores among genotypes and allele status of PER3 VNTR (rs57875989). Conclusions: We could not confirm that the PER3 VNTR is associated with diurnal preference in a Korean healthy young population. The future studies need to investigate the association between diurnal preference and other polymorphisms of PER3 gene in larger sample of Korean young healthy population.