• 한국도서관정보학회지
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• 제37권1호
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• pp.283-303
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• 2006

기록물에 대한 접근서비스는 그 이용자에 대한 이해를 기반으로 한다. 본 연구는 보다 효율적인 인터넷 상에서의 기록정보서비스를 위하여 인터넷에서 기록물을 이용하는 이용자들은 누구이고, 어떻게, 폐 기록물을 이용하는지 파악하고자 하였다. 또한 기록물 이용자들의 정보요구에 대한 서비스가 어떻게 이루어지고 있는지 파악하고자 하였다. 이를 위하여 $2000\sim2005$년간 국가기록원 게시판에 게시된 3,760건의 게시글을 분석하였다. 분석결과 이용자들은 주로 기록관리 업무에 관련한 질문과 특정 기록물 요청을 위한 질문을 하고 있었다 게시판 이용자들은 공무원, 기록관리업무 담당자, 가족을 대신한 질문자, 학생, 연구자, 미디어 제작자 등이었으며, 주로 단답형 질문을 하고 있었다. 이들 질문에 대한 응답글은 평균 5일 내에 게시되었다.

• Wind and Structures
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• 제6권6호
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• pp.451-470
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• 2003

The classical two-degree-of-freedom (2-d-o-f) "sectional model" is of common use to study the dynamics of suspension bridges. It takes into account the first pair of vertical and torsional modes of the bridge and describes well global oscillations caused by wind actions on the deck, yielding very useful information on the overall behaviour and the aerodynamic and aeroelastic response; however, it does not consider relative oscillations between main cables and deck. On the contrary, the 4-d-o-f model described in the two Parts of this paper includes longitudinal deformability of the hangers (assumed linear elastic in tension and unable to react in compression) and thus allows to take into account not only global oscillations, but also relative oscillations between main cables and deck. In particular, when the hangers go slack, large nonlinear oscillations are possible; if the hangers remain taut, the oscillations remain small and essentially linear: the latter behaviour has been the specific object of Part I (Sepe and Augusti 2001), while the present Part II investigates the nonlinear behaviour (coexisting large and/or small amplitude oscillations) under harmonic actions on the cables and/or on the deck, such as might be generated by vortex shedding. Because of the discontinuities and strong nonlinearity of the governing equations, the response has been investigated numerically. The results obtained for sample values of mechanical and forcing parameters seems to confirm that relative oscillations cannot a priori be excluded for very long span bridges under wind-induced loads, and they can stimulate a discussion on the actual possibility of such phenomena.

• Bulletin of the Korean Chemical Society
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• 제27권5호
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• pp.718-724
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• 2006

The heterogeneous association behaviour of various concentration binary mixtures of mono alkyl ethers of ethylene glycol with ethyl alcohol were investigated by dielectric measurement in benzene solutions over the entire concentration range at 25 ${^{\circ}C}$. The values of static dielectric constant $\epsilon_0$ of the mixtures were measured at 1 MHz using a four terminal dielectric liquid test fixture and precision LCR meter. The high frequency limiting dielectric constant $\epsilon_\infty$ values were determined by measurement of refractive index $n_D$ ($\epsilon_\infty\;=\;n_D\;^2$). The measured values of $\epsilon_0$ and $\epsilon_\infty$ were used to evaluate the values of excess dielectric constant $\epsilon^E$, effective Kirkwood correlation factor $g^{eff}$ and corrective correlation factor $g_f$ of the binary polar mixtures to obtain qualitative and quantitative information about the H-bond complex formation. The non-linear behaviour of the observed $\epsilon_0$ values of the polar molecules and their mixtures in benzene solvent confirms the variation in the associated structures with change in polar mixture constituents concentration and also by dilution in non-polar solvents. Appearance of the maximum in $\epsilon^E$ values at different concentration of the polar mixtures suggest the formation of stable adduct complex, which depends on the molecular size of the mono alkyl ethers of ethylene glycol. Further, the observed $\epsilon^E$ < 0 also confirms the heterogeneous H-bond complex formation reduces the effective number of dipoles in these polar binary mixtures. In benzene solutions these polar molecules shows the maximum reduce in effective number of dipoles at 50 percent dilutions. But ethyl alcohol rich binary polar mixtures in benzene solvent show the maximum reduce in effective number of dipoles in benzene rich solutions.

• 대한수학교육학회지:수학교육학연구
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• 제16권1호
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• pp.43-58
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• 2006

이 연구의 목적은 브루소가 소개한 교수학적 계약에 관해 논의하는 것이다. 브루소는 수학과 수업 자체를 게임으로 모델 화하고 있는 바, 그 게임에는 나름대로 교사와 학생들이 지켜야 하는 여러 가지 숨겨진 규칙으로서의 교수학적 계약이 존재한다. 브루소는 수학과 수업의 어떤 숨겨진 규칙을 표현하기 위해 그것을 도입하였다. 그 규칙들은 암묵적이고 호혜적인 것으로, 특히 학생들이 위반하기 전에는 드러나지 않는다. 브루소는 교수학적 계약을 조작적으로 정의하기 위해 그것을 교사의 행동과 그것에 대응하는 학생의 행동으로 정의하였으나, 심리적 및 인식론적 차원에서 정의하지는 않았다. 그러나 교사의 교수 행동은 자신의 신념 체계와 인식론의 영향을 받는 만큼, 그에 대한 논의도 필요하다. 또, 브루소는 교사가 교수학적 계약을 위반하는 경우에 대해서도 충분히 논의하지 않고 있다.

• 보건교육건강증진학회지
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• 제16권1호
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• pp.167-185
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• 1999

The purpose of this study was to analyze the content of the sexual knowledge and sexual attitude of the results of 39 previous studies for the adolescence in Korea, 1976-1997. The basis for analysis was the Guidelines for Comprehensive Sexuality Education developed by the Sex Information and Education Council of the U. S.(SIECUS). SIECUS is consisted of six key concepts; Human development, Relationships, Personal skills, Sexual behaviour, Sexual health, Society and Health. The research consisted of 39 articles that met definitional criteria of content analysis. The results of the study were summarized as follows: 1. Knowledge: It was conducted 96.7% of human development, 90.0% of sexual health, 70.0% of sexual behaviour, 23.3% of society and culture. 2. Attitude: It was conducted 94.1% of sexual behaviour, 73.5% of relationships, 55.9% of sexual health, 41.1% of human development, 26.5% of society and culture, 11.8% of personal skills. 3. General characteristics: With regard to sexual knowledge, 50.0% of research were published 1980s, 43.3% were 1990s, and 6.7%were 1970s. As regard to sexual attitude, 50% of research were published 1980s, 45.5% were 1990s, and 2.9% were 1970s. In sample size, 23.1% of 600 over, 401-500 were 20.5%. In the research tool, it was developed by researcher mainly 66.7%, modified tool by researcher was 5.1%. The tested reliability of the research tool was only 27.9%. And 78.9% of the research was not tested in validity of tool.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1997년도 추계학술강연 및 발표대회 강연 및 발표논문 초록집
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• pp.7-7
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• 1997

During sintering of very porous green bodies, as obtained by compaction of hard powders - such as tungsten carbide or ceramics - or by injection moulding, important shrinkage occurs. Due to heterogeneous green density field, gravity effects, friction on the support, thermal gradients, etc., this shrinkage is often non-uniform, which' may induce significant shape changes. As the ratio of compact dimension to powder size is very high, the mechanics of continuum is relevant to model such phenomena. Thus numerical techniques, such as the finite element method can be used to simulate the sintering process and predict the final shape of the sintered part. Such type of simulation has much been developed in the last decade firstly for hot isostatic pressing and next for die compaction. Finite element modelling has been recently applied to free sintering. The simulation of sintering should be based on constitutive equations describing the thermo-mechanical behaviour of the material under any state of stress and any temperature which may arise within the sintering body. These equations can be drawn either from experimental data or from micromechanical models. The experiments usually consist in free sintering and sinter-forging tests. Indeed applying more complex loading conditions at high temperature under controlled atmosphere is delicate. Micromechanical models describe the constitutive behaviour of aggregates of spheres from the deformation of two-sphere contact either by viscous flow or grain boundary diffusion. Such models are not able to describe complex microstructure and mechanisms as observed in real materials but they can give some basic information on the formulation of constitutive equations. Practically both experimental and theoretical approaches can be coupled to identify the constitutive equations. Such procedure has been performed for modelling the sintering of compacts obtained by die pressing of a mixture of tungsten carbide and cobalt powders. The constitutive behaviour of this material during sintering has been described by a linear viscous constitutive model, whose functions have been fitted from results of free sintering and sinter-forging experiments. This model has next been introduced in ABAQUS finite element code to simulate the sintering of heterogeneous green compacts of various geometries at constant temperature. Examples of simulations are shown and compared with experiments.

• 터널과지하공간
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• 제23권4호
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• pp.280-287
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• 2013

터널의 안정성 평가방법 중 유한요소법이나 유한차분법과 같은 수치해석을 수행하면 정밀한 지반거동을 예측할 수 있으나 터널노선 전구간에 대한 수치해석은 경제적으로 비효율적이다. 따라서 본 연구에서는 이론해를 사용하고 이를 적용할 수 있도록 터널을 등가면적의 원형으로 가정하여 터널 전구간에 대한 안정성을 분석하는 방법을 제시하였다. 이를 실제 터널에 적용하여 터널 전구간에 대해 예상되는 변형거동과 정량적인 변형률 및 소성반경을 계산하였고 이로부터 변형을 적정한 수준 이내로 제한하기 위한 지보압을 제시하였다. 적용 결과 제안된 방법은 전체 터널 구간에 대한 신속한 안정성 평가와 주요 불안정 구간에 대한 정밀 해석이나 계측설계와 같은 후속조치를 위한 정량적 자료를 제공할 수 있음을 확인하였다.

• 셀메드
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• 제2권4호
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• pp.36.1-36.4
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• 2012

This study was carried out to investigate the neurobehavioural effects of the smoking of Carica papaya leaves based on ethnopharmacological information. Twenty -four rats used for the study were grouped into four groups namely; Groups 1 (Control, unexposed to any smoke) and Groups 2 - 4 (exposed to smoke from varying amount of pawpaw leaf powder). Groups 2, 3, and 4 were exposed to smoke from 6.25 g (low dose), 12.50 g (medium dose), and 18.75 g (high dose) of dry pawpaw leaves respectively in a smoking chamber twice daily for 21 one days with each exposure lasting 3 min. The spontaneous motor activities and locomotory behaviour of the animals were assessed using an open field maze and hole board maze test. The results showed that the smoking of Carica papaya leaves led to a significant (p < 0.05) increase in locomotory activities from $33.36{\pm}3.36$ (control) to $66.50{\pm}6.16$ (high dose), number of head dips (from $8.50{\pm}0.36$, to $12.83{\pm}0.87$) and rearing behaviour (from $14.83{\pm}0.74$, to $27.0{\pm}1.46$). However, the freezing durations as animals were introduced into the maze and grooming behaviour were significantly (p < 0.05) reduced in the treated groups. In conclusion, the increased ambulations and exploratory behaviours imply that the anxiety level is low in the treated groups compared to the control group which thus confirms that dry Carica papaya leaf may possibly contain psychoactive substance(s) that become active when smoked.

• Structural Engineering and Mechanics
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• 제39권1호
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• pp.125-145
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• 2011

Pushover analysis has gained significant popularity as an analytical tool for realistic determination of the inelastic behaviour of RC structures. Though significant work has been done to evaluate the demands realistically, the evaluation of capacity and realistic failure modes has taken a back seat. In order to throw light on the inelastic behaviour and capacity evaluation for the RC framed structures, a 3D Reinforced concrete frame structure was tested under monotonically increasing lateral pushover loads, in a parabolic pattern, till failure. The structure consisted of three storeys and had 2 bays along the two orthogonal directions. The structure was gradually pushed in small increments of load and the corresponding displacements were monitored continuously, leading to a pushover curve for the structure as a result of the test along with other relevant information such as strains on reinforcement bars at critical locations, failure modes etc. The major failure modes were observed as flexural failure of beams and columns, torsional failure of transverse beams and joint shear failure. The analysis of the structure was by considering all these failure modes. In order to have a comparison, the analysis was performed as three different cases. In one case, only the flexural hinges were modelled for critical locations in beams and columns; in second the torsional hinges for transverse beams were included in the analysis and in the third case, joint shear hinges were also included in the analysis. It is shown that modelling and capturing all the failure modes is practically possible and such an analysis can provide the realistic insight into the behaviour of the structure.

• Steel and Composite Structures
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• 제32권1호
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• pp.1-19
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• 2019

The aim of the paper is the prediction of the seismic collapse mode of steel storage pallet racks under seismic loads. The attention paid by the researchers on the behaviour of the industrial steel storage pallets racks is increased over the years thanks to their high dead-to-live load ratio. In fact, these structures, generally made by cold-formed thin-walled profiles, present very low structural costs but can support large and expensive loads. The paper presents a prediction of the seismic collapse modes of multi-storey racks. The analysis of the possible collapse modes has been made by an approach based on the kinematic theorem of plastic collapse extended to the second order effects by means of the concept of collapse mechanism equilibrium curve. In this way, the dissipative behaviour of racks is determined with a simpler method than the pushover analysis. Parametric analyses have been performed on 24 racks, differing for the geometric layout and cross-section of the components, designed in according to the EN16618 and EN15512 requirements. The obtained results have highlighted that, in all the considered cases, the global collapse mechanism, that is the safest one, never develops, leading to a dangerous situation that must be avoided to preserve the structure during a seismic event. Although the studied racks follow all the codes prescriptions, the development of a dissipative collapse mechanism is not achieved. In addition, also the variability of load distribution has been considered, reflecting the different pallet positions assumed during the in-service life of the racks, to point out its influence on the collapse mechanism. The information carried out from the paper can be very useful for designers and manufacturers because it allows to better understand the racks behaviour in seismic load condition.