• 한국재료학회지
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• 제29권11호
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• pp.684-689
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• 2019

Single crystals, which have complexed composition, are fabricated by solid state grain growth. However, it is hard to achieve stable properties in a single crystal due to trapped pores. Aerosol deposition (AD) is suitable for fabrication of single crystals with stable properties because this process can make a high density coating layer. Because of their unique features (nano sized grains, stress inner site), it is hard to fabricate single crystals, and so studies of grain growth behavior of AD film are essential. In this study, a $BaTiO_3$ coating layer with ${\sim}9{\mu}m$ thickness is fabricated using an aerosol deposition method on (100) and (110) cut $SrTiO_3$ single crystal substrates, which are adopted as seeds for grain growth. Each specimen is heat-treated at various conditions (900, 1,100, and $1,300^{\circ}C$ for 5 h). $BaTiO_3$ layer shows different growth behavior and X-ray diffraction depending on cutting direction of $SrTiO_3$ seed. Rectangular pillars at $SrTiO_3$ (100) and laminating thin plates at $SrTiO_3$ (110), respectively, are observed.

• 한국도서관정보학회지
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• 제53권3호
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• pp.193-214
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• 2022

의미형성 이론은 주체의 다양성을 인정하면서도 정보추구 행위에 상당한 설득력을 부여한다. 이는 개인의 내적 영역, 대면, 조직, 매스커뮤니케이션 등의 소통과 관련된 다양한 시·공간적 맥락의 정보추구 현상을 설명하는 이론 및 방법론으로 활용되고 있다. 그러나 이론은 결과적으로 주체 개별의 인식론적 해석으로 귀결된다는 점에서 집단의 정보추구 행위를 설명하기 위한 이론이 될 수 없다. 또한, 이론의 목적은 소통 이론의 관점에서 발신자의 정보를 일방적으로 수용하는 수신자에서 벗어나 스스로 의미를 구성하는 수신자 중심의 소통 이론을 정립하고자 했다. 그러나 Dervin은 수신자의 외부의 정보와 수신자 사이의 관계를 설명하지 않고 객체정보의 존재를 용인한다. Dervin은 Popper(1972)의 세계 개념에 근거해 정보 개념을 수립하였기 때문에, 의미형성 이론의 관찰 대상은 세계3(객관적인 사유내용)이 아니라 세계3에서 발생하는 정보를 세계2(심리적 세계)가 받아들이는 의미형성 과정이다. 이러한 맥락에서 Dervin의 의미형성 이론은 집단 차원에서의 소통 행위를 설명할 수 없다.

• 아동학회지
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• 제5권
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• pp.107-119
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• 1984

In this article we reviewed the phenomena and processes of normalizing children through documentary records with interest in the aim of Montessori's education methods. The Montessori education method is based on the theory that all children should be respected and their works prized. The normalization of children does not mean only to turn abnormal children into normal ones, but to make normal characteristics - calmness, self-confidence, happiness or patience, etc.- which are latent in themselves, appear on the surface and remold them as new children. To achieve normalization some prerequisites are necessary. They are as follows: 1) The principle of freedom. The freedom in Montessori's education has some limits in prepared environments suitable for developing children as whole persons through their spontaneous activities. 2) Development of the phenomenon of children's attention. Arousal of their attention in the children's primitive inner impulse and sense of spiritual hunger. To satisfy their hunger children divert their interest to certain objects and come to repeated exercise of intelligence. 3) Concentration and repetitive phenomena. Repetition through children's concentration phenomenon is a natural and important fundamental behavior which controls their mental power. Repetitive behavior will form serious discipline and promote development of their intelligence.

• 한국보육지원학회지
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• 제12권6호
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• pp.169-188
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• 2016

The purpose of this study was to examine the influence of religious maturity of Christian teachers in child care centers on teacher-infant interaction, emotional labor and emotional intelligence. The survey was conducted on 173 Christian teachers of early-child classes who work in child care centers in Gyeonggi-do province. For the research analysis, frequency and Cronbach's ${\alpha}$ coefficient were calculated and regression analysis were conducted. The results are as follows. First, the affective and volitional factors from religious maturity of Christian teachers in child care centers have had a positive influence on the overall teacher-infant interaction. Second, the affective factor from religious maturity of Christian teachers in child care centers have had a negative influence on outward behavior, which is the lower variable of emotional work, and a positive influence on inner behavior. Third, the volitional factor from religious maturity of Christian teachers in child care centers have had a positive influence on perception of self-emotions, perception of others' emotion, emotional application, emotional control, and emotional intelligence overall.

• 한국공간구조학회논문집
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• 제2권4호
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• pp.61-76
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• 2002

The structure system that is discreterized by continuous shells is usually used to make a large space structures and these structures show the collapse mechanisms that are captured at over the limit load, and snap-through and bifurcation are most well known of it. For the collapse mechanism, rise-span ratio, element stiffness and load mode are main factor, which it give an effect to unstable behavior. Moreover, resist force of structure can be reduced by initial condition and initial imperfection significantly. In order to investigate the instability of shell structures, the finite deformation theory can be applied and it becomes a nonlinear mathematics in which use equation of tangential stiffness incrementally. With an initial imperfection, using simple example and Flow Truss Dome, the buckling characteristics of space truss is main purpose of this paper, and unstable behavior is studied by proposed the numerical method. Also, by using MIDAS, this research work analyzes displacements and inner forces as the design load of model, and the ratio of buckling load of design load is investigated.

• Composites Research
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• 제16권4호
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• pp.1-9
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• 2003

타이어 벨트층의 층간거동을 모사하기 위하여 2층 복합적층판을 고려하였다. 벨트층내의 층간전단응력 및 변형률을 측정하기위하여 3차원 유한요소해석을 수행하였다. 폭방향 전단변형률은 핀 이용법을 활용하여 측정되었다. 이들 실험 측정값은 적층판의 중앙부에서는 고전적층판이론과 그리고, 양가장자리부에서는 Kassapoglou 및 Kelsey의 이혼과 비교 하였다. 고무는 선형탄성체의 가정하였으며. 고투/코드 복한적층판은 직교이방성재질로 단순화 하였다 해석결과로부터, 층간박리의 원인인 층간전단응력은 고무내부의 양가장자리부에서 가장 큰 값을 보였다. 결과값은 중앙영역에서 고전적 층판이론과 매우 잘 일치하였으며. 양가장자리부에서는 이론값들과는 다소 차이를 보였다.

• 한국분무공학회지
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• 제12권1호
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• pp.11-17
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• 2007

The swirl spray for direct-injection spark-ignition (DISI) engines was investigated using a nozzle whose exit surface shape was cut with a certain tapered angle. The reason for the change in spray's characteristics at various tapered angles was explained by the data correlating the taper and flow angles. The spray tended to shift its characteristics from the symmetric to asymmetric when the tapered angle was increased; furthermore, the spray penetration and spray cone angle were also increased. When the tapered angle was greater than the $90^{\circ}$ minus flow angle, an opened hollow cone spray was formed because of the fuel impingement against the tapered surface area of the nozzle exit. This behavior indicates that the reduction in the air pressure difference between the inner and outer spray of the spray can be achieved. This behavior also promises the potential use of the tapered nozzle for the case where the independence of the spray performance from atmospheric pressure and fuel temperature is desired.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.1-6
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• 2008

When a saturated clay is sampled in an undisturbed manner from a bore hole, the sample extends vertically and shrinks horizontally under undrained conditions due to stress release. The conventional consolidation test specimen is trimmed from the expanded sample so that its diameter is equal to the inner diameter of the consolidation test ring, this test procedure does not reproduce the actual consolidation behavior. The measurement of sample extension was conducted by means of overcoring method found that the extension strains were 1 to 2%. To simulate the in-situ consolidation behavior, the consolidation test method that uses a specimen with a slightly smaller diameter than the inside diameter of consolidometer so that the specimen expands laterally to the inside of the ring.

• 전기화학회지
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• 제15권3호
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• pp.149-153
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• 2012

The $Cu_2O/TiO_2$ inverse opal heterojunction arrays were developed by electrochemical deposition of $Cu_2O$ nanoparticles on $TiO_2$ inverse opal arrays. The $Cu_2O$ nanoparticles completely filled the inner pores of $TiO_2$ inverse opal film (prepared by liquid phase deposition with an average thickness of 400 nm) and covered the entire area; exhibiting high crystalline properties of anatase and cubic phase from $TiO_2$ and $Cu_2O$, respectively. From asymmetric current-voltage profile, it was noticeable that a heterojunction was well formed for charge transport from $Cu_2O$ to $TiO_2$ film resulting from the enhanced charge separation yield. In addition, increased photocurrent of 0.19 $mA/cm^2$ (versus 0.08 $mA/cm^2$ under dark condition) was obtained at -0.35 V from the heterojunction structure in the 0.5M $Na_2SO_4$ solution.

• 한국세라믹학회지
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• 제19권1호
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• pp.51-57
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• 1982

The clinckers were obtained when a raw mixture consisted of limestone, slags and gypsum was burned at 134$0^{\circ}C$ for 30 minutes, and 128$0^{\circ}C$ for 30 minutes adding $CaF_2$ as a flux. The principal compounds of these clinkers were $C_3S_2$, $\beta-C_2S$, $C_1A_3{\bar{S}}$. To investigate hydration behavior, cements were made and hydrated at constant humidity cabinet (W/C=0.5 20$\pm 1^{\circ}C$). X-ray diffractometer, SEM, and conduction calorimeter were employed to examine the hydration behavior. The hydrates were mainly C-S-H, ettringite, $Ca(OH)_2$. By the hydration of $C_3S$ and $C_4A_3\bar{S}$, the needle-like ettringite filling the inner vacant spaces of the hardened body might contribute to the rapid-hardening and high-strength phenomena. Furthermore, the hardened body became stronger due to the hydration of $C_2S$ at later period. The addition of granulated blastfurnace slags have a potential to be a blended cement.