• Animal cells and systems
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• v.7 no.2
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• pp.111-117
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• 2003

Ecological aspects of Cryptocercus kyebangensis life history were investigated via laboratory rearing and field observations. The number of antennal segments and head width were used to classify the first four instars. The results, which combine both the field collection and the laboratory rearing, indicate that eleven instars occur in C. kyebangensis. It supports the proposal on the number of instars of Park and Choe (2003c) based on field collections. A total of 388 nymps from 13 colonies were collected prior to winter to investigate overwintering stages. Of them,4％ (n = 17) were the second instars, 57％ (n = 220) were the third instars, and 39％ (n = 151) were the fourth instars, respectively. Thus, most of them overwinter in the third or fourth instars. The results indicate that young nymphs of C. kyebangensis have to reach at least 3rd or 4th instar to survive low temperature environment of winter. According to seasonal dynamics of populations, C. kyebangensis reaches adulthood in the summer of the fourth or fifth year (4-5 yr span) after their birth.

• Journal of the Korea Furniture Society
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• v.28 no.3
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• pp.135-144
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• 2017

The development of human civilization has been accompanied by a corresponding development of storage facilities. In particular, the storage of residential spaces not only performs the storage management function for personal property but also is considered an important prerequisite for a comfortable life. While examining the history of the transformation of built-in furniture, this study emphasizes the social and cultural implications of Korean residences. Therefore, We attempt to uncover the Korean characteristics that can be discovered in the transformation of storage furniture according to the changes that occurred in Korean residential forms following the modern era and to question the problematic issues of the built-in furniture in Korea.

• Journal of The Korean Association For Science Education
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• v.27 no.2
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• pp.134-143
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• 2007

This study explores visitor learning in a natural history museum from the perspectives of situated learning. The purpose of this study is to understand how the visitors construct knowledge from museum experiences through dyadic discourses. The participants were two university students. They moved naturally through the exhibition with no predetermined path in a natural history museum in Korea. Data were collected in the form of audio-recorded dyadic discourses at and between exhibits and were transcribed. The transcription was coded using the conversation coding scheme, and categorized into specific learning types. The findings included (1) the characteristics of learning talks and (2) learning types created by dyadic discourses at and between exhibitions within learning contexts as museum learning experiences. Implications and future research related to visitor learning in informal learning settings were discussed based on the findings.

• Journal of Korean Neurosurgical Society
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• v.55 no.1
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• pp.61-63
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• 2014

A differential diagnosis between neurosarcoidosis and neurosyphilis is particularly problematic in patients with a positive serologic result for syphilis. We report here a patient with a solitary cavernous sinus sarcoidosis who had a history of syphilis and showed rapidly progressing cavernous sinus syndrome. A transsphenoidal biopsy was performed and a histopathologic examination revealed a non-caseating granuloma with an asteroid body. His facial pain disappeared after steroid therapy. He received oral prednisolone for one year. A follow-up magnetic resonance imaging of the brain revealed resolution of the mass over the cavernous sinus. Particularly in patients with a history of syphilis, neurosyphilis should be included in a differential diagnosis of neurosarcoidosis.

• Journal of Mechanical Science and Technology
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• v.19 no.2
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• pp.549-557
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• 2005

The requirements of multi-resolution models of feature-based solids, which represent an object at many levels of feature detail, are increasing for engineering purposes, such as analysis, network-based collaborative design, virtual prototyping and manufacturing. To provide multi-resolution models for various applications, it is essential to generate adequate solid models at varying levels of detail (LOD) after feature rearrangement, based on the LOD criteria. However, the non-commutative property of the union and subtraction Boolean operations is a severe obstacle to arbitrary feature rearrangement. To solve this problem we propose history-based Boolean operations that satisfy the commutative law between union and subtraction operations by considering the history of the Boolean operations. Because these operations guarantee the same resulting shape as the original and reasonable shapes at the intermediate LODs for an arbitrary rearrangement of its features, various LOD criteria can be applied for multi-resolution modeling in different applications.

• Communications of Mathematical Education
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• v.23 no.2
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• pp.297-312
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• 2009

We study the process of horizontal and vertical mathematization on the polyhedron problems through the history of mathematics, computer experiments, problem posing, and justifications. In particular, we explore the Hamilton cycle problem, coloring problem, and folding net construction on the Archimedean and Catalan polyhedrons. In this paper, we present our mathematical results on the polyhedron problems, and we also present some unsolved problems that we found. We found that the history of mathematics and mathematical experiments are very useful in such R&E exploration as polyhedron problem posing and solving project.

• The Korean Journal of Emergency Medical Services
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• v.23 no.3
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• pp.123-134
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• 2019

Purpose: This study aimed to analyze the number of patients with and without medical history transported to the emergency department due to changes in daily temperature and season. Methods: Data on emergency activity sheet and daily weather were collected from March 2016 to February 2017 in the city of Gyeonggi-do. In total, 13,531 patients were transferred to the emergency department in 119 ambulance. Data were analyzed using the Statistical Package for the Social Sciences (version 21). Results: The daily average number of patients transferred was the highest in August and September, i.e., the summer season. The higher the daily highest and lowest temperatures, higher the daily average number of patients transferred. In contrast, patients with medical history of hypertension, diabetes, heart disease, cerebrovascular disease, and pulmonary disease had a higher incidence of transfers in the winter season and on days with lower temperature. Conclusion: The results indicate that as people become more active during the summer when temperatures are high, the chances of daily emergencies increases, whereas patients with medical history are more likely to experience emergencies when the temperatures were lower. Hence, 119 ambulances will have to be prepared in advance to deal with this trend.

• Journal for History of Mathematics
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• v.25 no.4
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• pp.83-99
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• 2012

The conic sections are defined as algebraic expressions using the focus and the directrix in the high school curriculum. However it is difficult that students understand the conic sections without environment which they can manipulate the conic sections. To make up for this weak point, we have found the evidence for generating method of a conic section through a sundial and investigated the history of terms 'focus', 'directrix' and the tool of drawing them continuously.

• Development and Reproduction
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• v.18 no.4
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• pp.259-266
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• 2014

The egg development and early life history of Korean spotted sleeper, Odontobutis interrupta which is Korean endemic species from Sora-choen was investigated. The Korean spotted sleeper were caught at Sora-myeon, Yeosu-si, Jeollanamdo, from Korea at May in 2014. The fertilized eggs were $4.23{\pm}0.05mm$ in long diameter and had oil globules. Hatching time of the embryo began about 442 hr 14 min after fertilization under water temperature of $19.5^{\circ}C$. The newly hatched larvae were $4.27{\pm}0.35mm$ in total length and their anus were not yet opened. 3 days after hatching postlarvae was measured $6.20{\pm}0.11mm$ in total length. 10 days after hatching postlarvae was measured $6.69{\pm}0.14mm$ in total length.

• ALGAE
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• v.20 no.4
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• pp.325-331
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• 2005

Populations of Campylaephora borealis (Nakamura) Seo, Cho et Boo and C. crassa (Okamura) Nakamura show a year-around occurrence of all life-history stages. Such a concurrency of life-history stages produces problems in recognizing species in the field. Here, we invesitgated the morphological variation and life-history stages of both species using a statistical character analysis. Life-history stage was correlated with the seawater temperature in C. borealis, whereas it was dependant on biomass in C. crassa. Thalli had dichotomous branches with adaxial branchlets. The statistics showed that the seasonal change in morphology of C. borealis was significantly different from that of C. crassa in seven qualitative characters and five quantitative characters (p < 0.001), although six quantitative features including tetrasporangial size were similar in both species. The morphological difference between the two species may be due to the annual variation of branchlet number and the variance of branch subangle.