• Journal of applied mathematics & informatics
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• 제29권1_2호
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• pp.267-277
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• 2011

This paper is concerned with eigenvalues of second-order vector equations on time scales with boundary value conditions. Properties of eigenvalues and matrix-valued solutions are studied. Relationships between eigenvalues of different boundary value problems are discussed.

• Journal of applied mathematics & informatics
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• 제28권3_4호
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• pp.877-882
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• 2010

In this paper, a third-order three-point boundary value problem on time scales is considered. We establish criteria for the existence of a solution and a positive solution by using the Leray-Schauder fixed point theorem. An example is also given to illustrate our results.

• 충청수학회지
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• 제27권4호
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• pp.745-751
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• 2014

In this paper we introduce the interval-valued Henstock integral on time scales and investigate some properties of these integrals.

• 대한지리학회지
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• 제42권5호
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• pp.691-709
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• 2007

본 연구는 한국 주택정치에서의 '지리적 스케일의 사회적 정치적 구성(social and political construction of geographical scale)'을 분석하였다. 최근 미국 및 유럽에서 도시지리학을 포함한 인문지리학 분야에서 관심을 끌고 있는 주제 중 하나는 '지리적 스케일의 사회적 정치적 구성(또는 생산)'이다. 이에 관한 논의의 출발점은 바로 공간적 스케일은 존재론적으로 미리 주어지거나 고정되어 있다기 보다는 사회적으로 구성되며, 정치적인 경쟁의 대상물이 될 수 있다는 인식이다. 'tm케일의 정치(politics of scale)' 또는 '지리적(공간적) 스케일의 사회적 정치적 구성(생산)'에 관한 기존의 연구들은 사회운동(social movement)에서 서로 다른 공간적 스케일이 어떻게 활용되었으며 접목되었는지에 연구의 초점을 두었다. '스케일의 정치' 관련 논문들은 사회운동에서의 스케일의 역할을 '스케일 상승(up-scaling)' 또는 '정치적 행동의 스케일(scales of activism)' 위주로 논의하였다. 반면에 풀뿌리 시민사회운동에서의 스케일의 역할 연구라는 특성으로 인해 '스케일 하강(down-scaling)' 또는 '규제의 스케일(scales of regulation)' 논의는 미약하다. 한편, '스케일의 정치' 논의는 스케일의 이용을 통한 소수정치세력 및 사회소외층의 정치적 사회적 '임파워먼트(empowerment)' 과정에 연구의 초점을 두었다. 하지만, 기존의 '스케일의 정치'와 관련해서 어떻게 스케일이(특히 '스케일 하강'이) 무특권 사회집단을 소외하고 배제시키는지에 사용될 수 있는지, 그리고 공간의 생산 및 재생산을 조절할 수 있는지에 대한 연구는 미비하다. 한국 정부는 주택시장 관리 체제 및 제도 하에서 '스케일 도약(jumping scales)' 구체적으로 '스케일 하강'을 통해 여러 지리적 스케일에서의 주택 공간 생산 및 재생산에 대한 헤게모니를 가지게 되었다. 한국 정부는 주택 개발에 대한 다스케일적(multiscalar) 정책을 사용함과 동시에 중앙 정부, 지방 자치단체, 정부 산하 주택 관련 기관, 그리고 한국 다국적 기업(재벌) 간의 다양한 스케일에서의 제도적 네트워킹을 통해 '스케일 도약' 능력을 점점 더 획득하게 되었다. 전통적으로 지리적 스케일은 분석의 공간 단위 또는 범주로 인식되어 왔다. 하지만, 지리적 스케일은 사회적 내포(social inclusion), 사회적 배제(social exclusion), 정당화(legitimation)의 수단이 될 수 있다. 사회적으로 그리고 정치적으로 연대할 또는 배제할 기관 또는 조직을 선택하는 것 자체가 조직 네트워킹시의 공간적 스케일의 선택과 범위의 결정을 수반하며, 이는 '정치의 스케일 공간성(scale spatiality politics)'과 밀접히 연관되어 있다. 다양한 형태의 '규제의 스케일'을 전개해 온 한국 정부는 정부의 주택 개발 논리의 정당화를 위해 재벌, 고소득층, 중산층을 의사결정 과정에 포함시켰으나, 국지적 스케일에서의 서민 조직들과 사회소외계층을 의사결정 과정으로부터 제외시켰다.

• ALGAE
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• 제19권3호
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• pp.277-282
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• 2004

Prymnesium patelliferum was collected from Hwajinpo, South Korea in November 2002. This is the first record of P. patelliferum in Korea waters. The characteristic shape of P. patelliferum was that of a rice grain. Cells were sub spherical or elongate, and sometimes slightly compressed. The motile cells of P. patelliferum (8-10 ㎛ long, 5-6 ㎛ broad) prossessed two equal or sub equal flagella(10.5-13 ㎛) and a short non-coiling haptonema (3-5 ㎛). The cell was covered by two layers of organic scales, which were important taxonomic characteristics. Internal scales were a narrow inflexed rim on the distal face, a thickening central and radial fibrillar pattern. External scales were very similar to internal scales with relatively tall upright rims. The ridges were in quadrants with 11-12 ridges per quadrant.

• Structural Engineering and Mechanics
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• 제61권2호
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• pp.275-282
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• 2017

The Fleck-Hutchinson theory on strain gradient plasticity (SGP), proposed in Adv. Appl Mech 33 (1997) 295, has recently been reformulated by adopting the strategy of decomposing the second order strain presented by Lam et al. in J Mech Pays Solids 51 (2003) 1477. The newly built SGP satisfies the non negativity of plastic dissipation, which is still an outstanding issue in other SGP theories. Furthermore, it explicitly shows how elastic strain gradients and corresponding elastic characteristic length scales come into play in general elastic-plastic loading histories. In this study, the relation between elastic length scales and plastic length scales is investigated by taking wire torsion as an example. It is concluded that the size effects arising when two sets of length scales are of the same order are essentially elastic instead of plastic.

• 대한기계학회논문집A
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• 제27권12호
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• pp.2110-2117
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• 2003

A physics-based material removal model in various scales is described and a feature scale simulation for a chemical mechanical polishing (CMP) process is performed in this work. Three different scales are considered in this model, i.e., abrasive particle scale, asperity scale and wafer scale. The abrasive particle and the asperity scales are combined together and then homogenized to result in force balance conditions to be satisfied in the wafer scale using an extended Greenwood-Williamson and Whitehouse-Archard statistical model that takes into consideration the joint distribution of asperity heights and asperity tip radii. The final computation is made to evaluate the material removal rate in wafer scale and a computer simulation is performed for detailed surface profile variations on a representative feature. The results show the dependence of the material removal rate on the joint distribution, applied external pressure, relative velocity, and other operating conditions and design parameters.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2007년도 한국음성과학회 공동학술대회 발표논문집
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• pp.257-260
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• 2007

This study was designed to compare the self-rating scales (SSS, S-24, P-FA, and PSI) translated into Korean in adults with stuttering. Eighteen adults with stuttering were participated. Each scale was divided into two sub-categories, avoidance and locus of control. The correlations among the scales and among the sub-categories were evaluated. Objective stuttering severity and self-rated stuttering severity were compared. Results indicated that those scales were significantly correlated. Total score in each scale and each sub-category were also significantly correlated. There were no significant differences in total score nor subjective stuttering severity with objective stuttering severity. The self-rating scales in adults with stuttering currently used in clinics and research areas in Korea are suitable tools that adults with stuttering can evaluate the characteristics of and attitudes for stuttering subjectively.

• 한국가시화정보학회지
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• 제20권1호
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• pp.38-44
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• 2022

An interscale transport of the turbulent kinetic energy (TKE) and Reynolds shear stress (RSS) is examined in an adverse pressure gradient (APG) turbulent boundary layer (TBL). The direct numerical simulation data of an APG TBL at Re_τ = 834 and β = 1.45 is employed. The TKE and RSS transport equations are divided into large and small scales, leading to the introduction of interscale transport. The TKE mainly transfers from large scales to small ones in the outer region, and vice versa for the RSS. An interscale transport of TKE and inverse interscale transport of RSS are amplified by APG, and the latter results in the increase in large scales of TKE production. Some of outer large scales of enhanced TKE transfer to small scales and then dissipate by viscosity, and the remains dissipate turbulent-non-turbulent interfaces by turbulent transport.

• 한국과학교육학회지
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• 제16권2호
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• pp.217-225
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• 1996

Science-related attitudes, perceptions of science classroom environments, and their relationships were investigated for a sample of 535 primary and secondary school students. Two scales of the Test of Science-Related Attitudes and five scales of the Classroom Environment Scale(CES) were administered. Students' perceptions of preferred science classroom environments were also investigated using the same scales of the CES and compared with those of actual classroom environments. The results indicated the primary school students had the most positive attitudes on Enjoyment of Science Lesson and Career Interest in Science. They also had the highest scores on perceptions of actual classroom environments, while the high school students had the lowest scores. Regarding the relationships between science-related attitudes and perceptions of classroom environments, multiple correlations for the five scales of the CES were found to be significant(p<01). The scores of four scales-Involvement, Teacher Support, Order and Organization, Rule Clarity-are significantly correlated with the scores of Enjoyment of Science Lesson. Students' perceptions of preferred classroom environments on the four scales of the CES are significantly higher than those in actual environments. However, students' perceptions of actual environments on Task Orientation are similar to those of preferred environments, and are not significantly correlated with Enjoyment of Science Lesson. Educational implications are discussed.